remove support for 'trademark files'

[unleashed/tickless.git] / kernel / os / zone.c

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
 * Copyright 2015, Joyent Inc. All rights reserved.
 * Copyright (c) 2016 by Delphix. All rights reserved.
 */

/*
 * Zones
 *
 *   A zone is a named collection of processes, namespace constraints,
 *   and other system resources which comprise a secure and manageable
 *   application containment facility.
 *
 *   Zones (represented by the reference counted zone_t) are tracked in
 *   the kernel in the zonehash.  Elsewhere in the kernel, Zone IDs
 *   (zoneid_t) are used to track zone association.  Zone IDs are
 *   dynamically generated when the zone is created; if a persistent
 *   identifier is needed (core files, accounting logs, audit trail,
 *   etc.), the zone name should be used.
 *
 *
 *   Global Zone:
 *
 *   The global zone (zoneid 0) is automatically associated with all
 *   system resources that have not been bound to a user-created zone.
 *   This means that even systems where zones are not in active use
 *   have a global zone, and all processes, mounts, etc. are
 *   associated with that zone.  The global zone is generally
 *   unconstrained in terms of privileges and access, though the usual
 *   credential and privilege based restrictions apply.
 *
 *
 *   Zone States:
 *
 *   The states in which a zone may be in and the transitions are as
 *   follows:
 *
 *   ZONE_IS_UNINITIALIZED: primordial state for a zone. The partially
 *   initialized zone is added to the list of active zones on the system but
 *   isn't accessible.
 *
 *   ZONE_IS_INITIALIZED: Initialization complete except the ZSD callbacks are
 *   not yet completed. Not possible to enter the zone, but attributes can
 *   be retrieved.
 *
 *   ZONE_IS_READY: zsched (the kernel dummy process for a zone) is
 *   ready.  The zone is made visible after the ZSD constructor callbacks are
 *   executed.  A zone remains in this state until it transitions into
 *   the ZONE_IS_BOOTING state as a result of a call to zone_boot().
 *
 *   ZONE_IS_BOOTING: in this shortlived-state, zsched attempts to start
 *   init.  Should that fail, the zone proceeds to the ZONE_IS_SHUTTING_DOWN
 *   state.
 *
 *   ZONE_IS_RUNNING: The zone is open for business: zsched has
 *   successfully started init.   A zone remains in this state until
 *   zone_shutdown() is called.
 *
 *   ZONE_IS_SHUTTING_DOWN: zone_shutdown() has been called, the system is
 *   killing all processes running in the zone. The zone remains
 *   in this state until there are no more user processes running in the zone.
 *   zone_create(), zone_enter(), and zone_destroy() on this zone will fail.
 *   Since zone_shutdown() is restartable, it may be called successfully
 *   multiple times for the same zone_t.  Setting of the zone's state to
 *   ZONE_IS_SHUTTING_DOWN is synchronized with mounts, so VOP_MOUNT() may check
 *   the zone's status without worrying about it being a moving target.
 *
 *   ZONE_IS_EMPTY: zone_shutdown() has been called, and there
 *   are no more user processes in the zone.  The zone remains in this
 *   state until there are no more kernel threads associated with the
 *   zone.  zone_create(), zone_enter(), and zone_destroy() on this zone will
 *   fail.
 *
 *   ZONE_IS_DOWN: All kernel threads doing work on behalf of the zone
 *   have exited.  zone_shutdown() returns.  Henceforth it is not possible to
 *   join the zone or create kernel threads therein.
 *
 *   ZONE_IS_DYING: zone_destroy() has been called on the zone; zone
 *   remains in this state until zsched exits.  Calls to zone_find_by_*()
 *   return NULL from now on.
 *
 *   ZONE_IS_DEAD: zsched has exited (zone_ntasks == 0).  There are no
 *   processes or threads doing work on behalf of the zone.  The zone is
 *   removed from the list of active zones.  zone_destroy() returns, and
 *   the zone can be recreated.
 *
 *   ZONE_IS_FREE (internal state): zone_ref goes to 0, ZSD destructor
 *   callbacks are executed, and all memory associated with the zone is
 *   freed.
 *
 *   Threads can wait for the zone to enter a requested state by using
 *   zone_status_wait() or zone_status_timedwait() with the desired
 *   state passed in as an argument.  Zone state transitions are
 *   uni-directional; it is not possible to move back to an earlier state.
 *
 *
 *   Zone-Specific Data:
 *
 *   Subsystems needing to maintain zone-specific data can store that
 *   data using the ZSD mechanism.  This provides a zone-specific data
 *   store, similar to thread-specific data (see pthread_getspecific(3C)
 *   or the TSD code in uts/common/disp/thread.c.  Also, ZSD can be used
 *   to register callbacks to be invoked when a zone is created, shut
 *   down, or destroyed.  This can be used to initialize zone-specific
 *   data for new zones and to clean up when zones go away.
 *
 *
 *   Data Structures:
 *
 *   The per-zone structure (zone_t) is reference counted, and freed
 *   when all references are released.  zone_hold and zone_rele can be
 *   used to adjust the reference count.  In addition, reference counts
 *   associated with the cred_t structure are tracked separately using
 *   zone_cred_hold and zone_cred_rele.
 *
 *   Pointers to active zone_t's are stored in two hash tables; one
 *   for searching by id, the other for searching by name.  Lookups
 *   can be performed on either basis, using zone_find_by_id and
 *   zone_find_by_name.  Both return zone_t pointers with the zone
 *   held, so zone_rele should be called when the pointer is no longer
 *   needed.  Zones can also be searched by path; zone_find_by_path
 *   returns the zone with which a path name is associated (global
 *   zone if the path is not within some other zone's file system
 *   hierarchy).  This currently requires iterating through each zone,
 *   so it is slower than an id or name search via a hash table.
 *
 *
 *   Locking:
 *
 *   zonehash_lock: This is a top-level global lock used to protect the
 *       zone hash tables and lists.  Zones cannot be created or destroyed
 *       while this lock is held.
 *   zone_status_lock: This is a global lock protecting zone state.
 *       Zones cannot change state while this lock is held.  It also
 *       protects the list of kernel threads associated with a zone.
 *   zone_lock: This is a per-zone lock used to protect several fields of
 *       the zone_t (see <sys/zone.h> for details).  In addition, holding
 *       this lock means that the zone cannot go away.
 *   zone_nlwps_lock: This is a per-zone lock used to protect the fields
 *       related to the zone.max-lwps rctl.
 *   zone_mem_lock: This is a per-zone lock used to protect the fields
 *       related to the zone.max-locked-memory and zone.max-swap rctls.
 *   zone_rctl_lock: This is a per-zone lock used to protect other rctls,
 *       currently just max_lofi
 *   zsd_key_lock: This is a global lock protecting the key state for ZSD.
 *   zone_deathrow_lock: This is a global lock protecting the "deathrow"
 *       list (a list of zones in the ZONE_IS_DEAD state).
 *
 *   Ordering requirements:
 *       pool_lock --> cpu_lock --> zonehash_lock --> zone_status_lock -->
 *              zone_lock --> zsd_key_lock --> pidlock --> p_lock
 *
 *   When taking zone_mem_lock or zone_nlwps_lock, the lock ordering is:
 *      zonehash_lock --> a_lock --> pidlock --> p_lock --> zone_mem_lock
 *      zonehash_lock --> a_lock --> pidlock --> p_lock --> zone_nlwps_lock
 *
 *   Blocking memory allocations are permitted while holding any of the
 *   zone locks.
 *
 *
 *   System Call Interface:
 *
 *   The zone subsystem can be managed and queried from user level with
 *   the following system calls (all subcodes of the primary "zone"
 *   system call):
 *   - zone_create: creates a zone with selected attributes (name,
 *     root path, privileges, resource controls, ZFS datasets)
 *   - zone_enter: allows the current process to enter a zone
 *   - zone_getattr: reports attributes of a zone
 *   - zone_setattr: set attributes of a zone
 *   - zone_boot: set 'init' running for the zone
 *   - zone_list: lists all zones active in the system
 *   - zone_lookup: looks up zone id based on name
 *   - zone_shutdown: initiates shutdown process (see states above)
 *   - zone_destroy: completes shutdown process (see states above)
 *
 */

#include <sys/priv_impl.h>
#include <sys/cred.h>
#include <c2/audit.h>
#include <sys/debug.h>
#include <sys/file.h>
#include <sys/kmem.h>
#include <sys/kstat.h>
#include <sys/mutex.h>
#include <sys/note.h>
#include <sys/pathname.h>
#include <sys/proc.h>
#include <sys/project.h>
#include <sys/sysevent.h>
#include <sys/task.h>
#include <sys/systm.h>
#include <sys/types.h>
#include <sys/utsname.h>
#include <sys/vnode.h>
#include <sys/vfs.h>
#include <sys/systeminfo.h>
#include <sys/policy.h>
#include <sys/cred_impl.h>
#include <sys/contract_impl.h>
#include <sys/contract/process_impl.h>
#include <sys/class.h>
#include <sys/pool.h>
#include <sys/pool_pset.h>
#include <sys/pset.h>
#include <sys/strlog.h>
#include <sys/sysmacros.h>
#include <sys/callb.h>
#include <sys/vmparam.h>
#include <sys/corectl.h>
#include <sys/ipc_impl.h>
#include <sys/klpd.h>

#include <sys/door.h>
#include <sys/cpuvar.h>
#include <sys/sdt.h>

#include <sys/uadmin.h>
#include <sys/session.h>
#include <sys/cmn_err.h>
#include <sys/modhash.h>
#include <sys/sunddi.h>
#include <sys/nvpair.h>
#include <sys/rctl.h>
#include <sys/fss.h>
#include <sys/brand.h>
#include <sys/zone.h>
#include <net/if.h>
#include <sys/cpucaps.h>
#include <vm/seg.h>
#include <sys/mac.h>

/*
 * This constant specifies the number of seconds that threads waiting for
 * subsystems to release a zone's general-purpose references will wait before
 * they log the zone's reference counts.  The constant's value shouldn't
 * be so small that reference counts are unnecessarily reported for zones
 * whose references are slowly released.  On the other hand, it shouldn't be so
 * large that users reboot their systems out of frustration over hung zones
 * before the system logs the zones' reference counts.
 */
#define ZONE_DESTROY_TIMEOUT_SECS       60

/* List of data link IDs which are accessible from the zone */
typedef struct zone_dl {
        datalink_id_t   zdl_id;
        nvlist_t        *zdl_net;
        list_node_t     zdl_linkage;
} zone_dl_t;

/*
 * cv used to signal that all references to the zone have been released.  This
 * needs to be global since there may be multiple waiters, and the first to
 * wake up will free the zone_t, hence we cannot use zone->zone_cv.
 */
static kcondvar_t zone_destroy_cv;
/*
 * Lock used to serialize access to zone_cv.  This could have been per-zone,
 * but then we'd need another lock for zone_destroy_cv, and why bother?
 */
static kmutex_t zone_status_lock;

/*
 * ZSD-related global variables.
 */
static kmutex_t zsd_key_lock;   /* protects the following two */
/*
 * The next caller of zone_key_create() will be assigned a key of ++zsd_keyval.
 */
static zone_key_t zsd_keyval = 0;
/*
 * Global list of registered keys.  We use this when a new zone is created.
 */
static list_t zsd_registered_keys;

int zone_hash_size = 256;
static mod_hash_t *zonehashbyname, *zonehashbyid;
static kmutex_t zonehash_lock;
static uint_t zonecount;
static id_space_t *zoneid_space;

/*
 * The global zone (aka zone0) is the all-seeing, all-knowing zone in which the
 * kernel proper runs, and which manages all other zones.
 *
 * Although not declared as static, the variable "zone0" should not be used
 * except for by code that needs to reference the global zone early on in boot,
 * before it is fully initialized.  All other consumers should use
 * 'global_zone'.
 */
zone_t zone0;
zone_t *global_zone = NULL;     /* Set when the global zone is initialized */

/*
 * List of active zones, protected by zonehash_lock.
 */
static list_t zone_active;

/*
 * List of destroyed zones that still have outstanding cred references.
 * Used for debugging.  Uses a separate lock to avoid lock ordering
 * problems in zone_free.
 */
static list_t zone_deathrow;
static kmutex_t zone_deathrow_lock;

/* number of zones is limited by virtual interface limit in IP */
uint_t maxzones = 8192;

/* Event channel to sent zone state change notifications */
evchan_t *zone_event_chan;

/*
 * This table holds the mapping from kernel zone states to
 * states visible in the state notification API.
 * The idea is that we only expose "obvious" states and
 * do not expose states which are just implementation details.
 */
const char  *zone_status_table[] = {
        ZONE_EVENT_UNINITIALIZED,       /* uninitialized */
        ZONE_EVENT_INITIALIZED,         /* initialized */
        ZONE_EVENT_READY,               /* ready */
        ZONE_EVENT_READY,               /* booting */
        ZONE_EVENT_RUNNING,             /* running */
        ZONE_EVENT_SHUTTING_DOWN,       /* shutting_down */
        ZONE_EVENT_SHUTTING_DOWN,       /* empty */
        ZONE_EVENT_SHUTTING_DOWN,       /* down */
        ZONE_EVENT_SHUTTING_DOWN,       /* dying */
        ZONE_EVENT_UNINITIALIZED,       /* dead */
};

/*
 * This array contains the names of the subsystems listed in zone_ref_subsys_t
 * (see sys/zone.h).
 */
static char *zone_ref_subsys_names[] = {
        "NFS",          /* ZONE_REF_NFS */
        "NFSv4",        /* ZONE_REF_NFSV4 */
        "SMBFS",        /* ZONE_REF_SMBFS */
        "MNTFS",        /* ZONE_REF_MNTFS */
        "LOFI",         /* ZONE_REF_LOFI */
        "VFS",          /* ZONE_REF_VFS */
        "IPC"           /* ZONE_REF_IPC */
};

/*
 * This isn't static so lint doesn't complain.
 */
rctl_hndl_t rc_zone_cpu_shares;
rctl_hndl_t rc_zone_locked_mem;
rctl_hndl_t rc_zone_max_swap;
rctl_hndl_t rc_zone_max_lofi;
rctl_hndl_t rc_zone_cpu_cap;
rctl_hndl_t rc_zone_nlwps;
rctl_hndl_t rc_zone_nprocs;
rctl_hndl_t rc_zone_shmmax;
rctl_hndl_t rc_zone_shmmni;
rctl_hndl_t rc_zone_semmni;
rctl_hndl_t rc_zone_msgmni;

const char * const zone_default_initname = "/sbin/init";
static char * const zone_prefix = "/zone/";
static int zone_shutdown(zoneid_t zoneid);
static int zone_add_datalink(zoneid_t, datalink_id_t);
static int zone_remove_datalink(zoneid_t, datalink_id_t);
static int zone_list_datalink(zoneid_t, int *, datalink_id_t *);
static int zone_set_network(zoneid_t, zone_net_data_t *);
static int zone_get_network(zoneid_t, zone_net_data_t *);

typedef boolean_t zsd_applyfn_t(kmutex_t *, boolean_t, zone_t *, zone_key_t);

static void zsd_apply_all_zones(zsd_applyfn_t *, zone_key_t);
static void zsd_apply_all_keys(zsd_applyfn_t *, zone_t *);
static boolean_t zsd_apply_create(kmutex_t *, boolean_t, zone_t *, zone_key_t);
static boolean_t zsd_apply_shutdown(kmutex_t *, boolean_t, zone_t *,
    zone_key_t);
static boolean_t zsd_apply_destroy(kmutex_t *, boolean_t, zone_t *, zone_key_t);
static boolean_t zsd_wait_for_creator(zone_t *, struct zsd_entry *,
    kmutex_t *);
static boolean_t zsd_wait_for_inprogress(zone_t *, struct zsd_entry *,
    kmutex_t *);

/*
 * Bump this number when you alter the zone syscall interfaces; this is
 * because we need to have support for previous API versions in libc
 * to support patching; libc calls into the kernel to determine this number.
 *
 * Version 1 of the API is the version originally shipped with Solaris 10
 * Version 2 alters the zone_create system call in order to support more
 *     arguments by moving the args into a structure; and to do better
 *     error reporting when zone_create() fails.
 * Version 3 alters the zone_create system call in order to support the
 *     import of ZFS datasets to zones.
 * Version 4 alters the zone_create system call in order to support
 *     Trusted Extensions.
 * Version 5 alters the zone_boot system call, and converts its old
 *     bootargs parameter to be set by the zone_setattr API instead.
 * Version 6 adds the flag argument to zone_create.
 */
static const int ZONE_SYSCALL_API_VERSION = 6;

/*
 * Certain filesystems (such as NFS and autofs) need to know which zone
 * the mount is being placed in.  Because of this, we need to be able to
 * ensure that a zone isn't in the process of being created/destroyed such
 * that nfs_mount() thinks it is in the global/NGZ zone, while by the time
 * it gets added the list of mounted zones, it ends up on the wrong zone's
 * mount list. Since a zone can't reside on an NFS file system, we don't
 * have to worry about the zonepath itself.
 *
 * The following functions: block_mounts()/resume_mounts() and
 * mount_in_progress()/mount_completed() are used by zones and the VFS
 * layer (respectively) to synchronize zone state transitions and new
 * mounts within a zone. This syncronization is on a per-zone basis, so
 * activity for one zone will not interfere with activity for another zone.
 *
 * The semantics are like a reader-reader lock such that there may
 * either be multiple mounts (or zone state transitions, if that weren't
 * serialized by zonehash_lock) in progress at the same time, but not
 * both.
 *
 * We use cv's so the user can ctrl-C out of the operation if it's
 * taking too long.
 *
 * The semantics are such that there is unfair bias towards the
 * "current" operation.  This means that zone halt may starve if
 * there is a rapid succession of new mounts coming in to the zone.
 */
/*
 * Prevent new mounts from progressing to the point of calling
 * VFS_MOUNT().  If there are already mounts in this "region", wait for
 * them to complete.
 */
static int
block_mounts(zone_t *zp)
{
        int retval = 0;

        /*
         * Since it may block for a long time, block_mounts() shouldn't be
         * called with zonehash_lock held.
         */
        ASSERT(MUTEX_NOT_HELD(&zonehash_lock));
        mutex_enter(&zp->zone_mount_lock);
        while (zp->zone_mounts_in_progress > 0) {
                if (cv_wait_sig(&zp->zone_mount_cv, &zp->zone_mount_lock) == 0)
                        goto signaled;
        }
        /*
         * A negative value of mounts_in_progress indicates that mounts
         * have been blocked by (-mounts_in_progress) different callers
         * (remotely possible if two threads enter zone_shutdown at the same
         * time).
         */
        zp->zone_mounts_in_progress--;
        retval = 1;
signaled:
        mutex_exit(&zp->zone_mount_lock);
        return (retval);
}

/*
 * The VFS layer may progress with new mounts as far as we're concerned.
 * Allow them to progress if we were the last obstacle.
 */
static void
resume_mounts(zone_t *zp)
{
        mutex_enter(&zp->zone_mount_lock);
        if (++zp->zone_mounts_in_progress == 0)
                cv_broadcast(&zp->zone_mount_cv);
        mutex_exit(&zp->zone_mount_lock);
}

/*
 * The VFS layer is busy with a mount; this zone should wait until all
 * of its mounts are completed to progress.
 */
void
mount_in_progress(zone_t *zp)
{
        mutex_enter(&zp->zone_mount_lock);
        while (zp->zone_mounts_in_progress < 0)
                cv_wait(&zp->zone_mount_cv, &zp->zone_mount_lock);
        zp->zone_mounts_in_progress++;
        mutex_exit(&zp->zone_mount_lock);
}

/*
 * VFS is done with one mount; wake up any waiting block_mounts()
 * callers if this is the last mount.
 */
void
mount_completed(zone_t *zp)
{
        mutex_enter(&zp->zone_mount_lock);
        if (--zp->zone_mounts_in_progress == 0)
                cv_broadcast(&zp->zone_mount_cv);
        mutex_exit(&zp->zone_mount_lock);
}

/*
 * ZSD routines.
 *
 * Zone Specific Data (ZSD) is modeled after Thread Specific Data as
 * defined by the pthread_key_create() and related interfaces.
 *
 * Kernel subsystems may register one or more data items and/or
 * callbacks to be executed when a zone is created, shutdown, or
 * destroyed.
 *
 * Unlike the thread counterpart, destructor callbacks will be executed
 * even if the data pointer is NULL and/or there are no constructor
 * callbacks, so it is the responsibility of such callbacks to check for
 * NULL data values if necessary.
 *
 * The locking strategy and overall picture is as follows:
 *
 * When someone calls zone_key_create(), a template ZSD entry is added to the
 * global list "zsd_registered_keys", protected by zsd_key_lock.  While
 * holding that lock all the existing zones are marked as
 * ZSD_CREATE_NEEDED and a copy of the ZSD entry added to the per-zone
 * zone_zsd list (protected by zone_lock). The global list is updated first
 * (under zone_key_lock) to make sure that newly created zones use the
 * most recent list of keys. Then under zonehash_lock we walk the zones
 * and mark them.  Similar locking is used in zone_key_delete().
 *
 * The actual create, shutdown, and destroy callbacks are done without
 * holding any lock. And zsd_flags are used to ensure that the operations
 * completed so that when zone_key_create (and zone_create) is done, as well as
 * zone_key_delete (and zone_destroy) is done, all the necessary callbacks
 * are completed.
 *
 * When new zones are created constructor callbacks for all registered ZSD
 * entries will be called. That also uses the above two phases of marking
 * what needs to be done, and then running the callbacks without holding
 * any locks.
 *
 * The framework does not provide any locking around zone_getspecific() and
 * zone_setspecific() apart from that needed for internal consistency, so
 * callers interested in atomic "test-and-set" semantics will need to provide
 * their own locking.
 */

/*
 * Helper function to find the zsd_entry associated with the key in the
 * given list.
 */
static struct zsd_entry *
zsd_find(list_t *l, zone_key_t key)
{
        struct zsd_entry *zsd;

        for (zsd = list_head(l); zsd != NULL; zsd = list_next(l, zsd)) {
                if (zsd->zsd_key == key) {
                        return (zsd);
                }
        }
        return (NULL);
}

/*
 * Helper function to find the zsd_entry associated with the key in the
 * given list. Move it to the front of the list.
 */
static struct zsd_entry *
zsd_find_mru(list_t *l, zone_key_t key)
{
        struct zsd_entry *zsd;

        for (zsd = list_head(l); zsd != NULL; zsd = list_next(l, zsd)) {
                if (zsd->zsd_key == key) {
                        /*
                         * Move to head of list to keep list in MRU order.
                         */
                        if (zsd != list_head(l)) {
                                list_remove(l, zsd);
                                list_insert_head(l, zsd);
                        }
                        return (zsd);
                }
        }
        return (NULL);
}

void
zone_key_create(zone_key_t *keyp, void *(*create)(zoneid_t),
    void (*shutdown)(zoneid_t, void *), void (*destroy)(zoneid_t, void *))
{
        struct zsd_entry *zsdp;
        struct zsd_entry *t;
        struct zone *zone;
        zone_key_t  key;

        zsdp = kmem_zalloc(sizeof (*zsdp), KM_SLEEP);
        zsdp->zsd_data = NULL;
        zsdp->zsd_create = create;
        zsdp->zsd_shutdown = shutdown;
        zsdp->zsd_destroy = destroy;

        /*
         * Insert in global list of callbacks. Makes future zone creations
         * see it.
         */
        mutex_enter(&zsd_key_lock);
        key = zsdp->zsd_key = ++zsd_keyval;
        ASSERT(zsd_keyval != 0);
        list_insert_tail(&zsd_registered_keys, zsdp);
        mutex_exit(&zsd_key_lock);

        /*
         * Insert for all existing zones and mark them as needing
         * a create callback.
         */
        mutex_enter(&zonehash_lock);    /* stop the world */
        for (zone = list_head(&zone_active); zone != NULL;
            zone = list_next(&zone_active, zone)) {
                zone_status_t status;

                mutex_enter(&zone->zone_lock);

                /* Skip zones that are on the way down or not yet up */
                status = zone_status_get(zone);
                if (status >= ZONE_IS_DOWN ||
                    status == ZONE_IS_UNINITIALIZED) {
                        mutex_exit(&zone->zone_lock);
                        continue;
                }

                t = zsd_find_mru(&zone->zone_zsd, key);
                if (t != NULL) {
                        /*
                         * A zsd_configure already inserted it after
                         * we dropped zsd_key_lock above.
                         */
                        mutex_exit(&zone->zone_lock);
                        continue;
                }
                t = kmem_zalloc(sizeof (*t), KM_SLEEP);
                t->zsd_key = key;
                t->zsd_create = create;
                t->zsd_shutdown = shutdown;
                t->zsd_destroy = destroy;
                if (create != NULL) {
                        t->zsd_flags = ZSD_CREATE_NEEDED;
                        DTRACE_PROBE2(zsd__create__needed,
                            zone_t *, zone, zone_key_t, key);
                }
                list_insert_tail(&zone->zone_zsd, t);
                mutex_exit(&zone->zone_lock);
        }
        mutex_exit(&zonehash_lock);

        if (create != NULL) {
                /* Now call the create callback for this key */
                zsd_apply_all_zones(zsd_apply_create, key);
        }
        /*
         * It is safe for consumers to use the key now, make it
         * globally visible. Specifically zone_getspecific() will
         * always successfully return the zone specific data associated
         * with the key.
         */
        *keyp = key;

}

/*
 * Function called when a module is being unloaded, or otherwise wishes
 * to unregister its ZSD key and callbacks.
 *
 * Remove from the global list and determine the functions that need to
 * be called under a global lock. Then call the functions without
 * holding any locks. Finally free up the zone_zsd entries. (The apply
 * functions need to access the zone_zsd entries to find zsd_data etc.)
 */
int
zone_key_delete(zone_key_t key)
{
        struct zsd_entry *zsdp = NULL;
        zone_t *zone;

        mutex_enter(&zsd_key_lock);
        zsdp = zsd_find_mru(&zsd_registered_keys, key);
        if (zsdp == NULL) {
                mutex_exit(&zsd_key_lock);
                return (-1);
        }
        list_remove(&zsd_registered_keys, zsdp);
        mutex_exit(&zsd_key_lock);

        mutex_enter(&zonehash_lock);
        for (zone = list_head(&zone_active); zone != NULL;
            zone = list_next(&zone_active, zone)) {
                struct zsd_entry *del;

                mutex_enter(&zone->zone_lock);
                del = zsd_find_mru(&zone->zone_zsd, key);
                if (del == NULL) {
                        /*
                         * Somebody else got here first e.g the zone going
                         * away.
                         */
                        mutex_exit(&zone->zone_lock);
                        continue;
                }
                ASSERT(del->zsd_shutdown == zsdp->zsd_shutdown);
                ASSERT(del->zsd_destroy == zsdp->zsd_destroy);
                if (del->zsd_shutdown != NULL &&
                    (del->zsd_flags & ZSD_SHUTDOWN_ALL) == 0) {
                        del->zsd_flags |= ZSD_SHUTDOWN_NEEDED;
                        DTRACE_PROBE2(zsd__shutdown__needed,
                            zone_t *, zone, zone_key_t, key);
                }
                if (del->zsd_destroy != NULL &&
                    (del->zsd_flags & ZSD_DESTROY_ALL) == 0) {
                        del->zsd_flags |= ZSD_DESTROY_NEEDED;
                        DTRACE_PROBE2(zsd__destroy__needed,
                            zone_t *, zone, zone_key_t, key);
                }
                mutex_exit(&zone->zone_lock);
        }
        mutex_exit(&zonehash_lock);
        kmem_free(zsdp, sizeof (*zsdp));

        /* Now call the shutdown and destroy callback for this key */
        zsd_apply_all_zones(zsd_apply_shutdown, key);
        zsd_apply_all_zones(zsd_apply_destroy, key);

        /* Now we can free up the zsdp structures in each zone */
        mutex_enter(&zonehash_lock);
        for (zone = list_head(&zone_active); zone != NULL;
            zone = list_next(&zone_active, zone)) {
                struct zsd_entry *del;

                mutex_enter(&zone->zone_lock);
                del = zsd_find(&zone->zone_zsd, key);
                if (del != NULL) {
                        list_remove(&zone->zone_zsd, del);
                        ASSERT(!(del->zsd_flags & ZSD_ALL_INPROGRESS));
                        kmem_free(del, sizeof (*del));
                }
                mutex_exit(&zone->zone_lock);
        }
        mutex_exit(&zonehash_lock);

        return (0);
}

/*
 * ZSD counterpart of pthread_setspecific().
 *
 * Since all zsd callbacks, including those with no create function,
 * have an entry in zone_zsd, if the key is registered it is part of
 * the zone_zsd list.
 * Return an error if the key wasn't registerd.
 */
int
zone_setspecific(zone_key_t key, zone_t *zone, const void *data)
{
        struct zsd_entry *t;

        mutex_enter(&zone->zone_lock);
        t = zsd_find_mru(&zone->zone_zsd, key);
        if (t != NULL) {
                /*
                 * Replace old value with new
                 */
                t->zsd_data = (void *)data;
                mutex_exit(&zone->zone_lock);
                return (0);
        }
        mutex_exit(&zone->zone_lock);
        return (-1);
}

/*
 * ZSD counterpart of pthread_getspecific().
 */
void *
zone_getspecific(zone_key_t key, zone_t *zone)
{
        struct zsd_entry *t;
        void *data;

        mutex_enter(&zone->zone_lock);
        t = zsd_find_mru(&zone->zone_zsd, key);
        data = (t == NULL ? NULL : t->zsd_data);
        mutex_exit(&zone->zone_lock);
        return (data);
}

/*
 * Function used to initialize a zone's list of ZSD callbacks and data
 * when the zone is being created.  The callbacks are initialized from
 * the template list (zsd_registered_keys). The constructor callback is
 * executed later (once the zone exists and with locks dropped).
 */
static void
zone_zsd_configure(zone_t *zone)
{
        struct zsd_entry *zsdp;
        struct zsd_entry *t;

        ASSERT(MUTEX_HELD(&zonehash_lock));
        ASSERT(list_head(&zone->zone_zsd) == NULL);
        mutex_enter(&zone->zone_lock);
        mutex_enter(&zsd_key_lock);
        for (zsdp = list_head(&zsd_registered_keys); zsdp != NULL;
            zsdp = list_next(&zsd_registered_keys, zsdp)) {
                /*
                 * Since this zone is ZONE_IS_UNCONFIGURED, zone_key_create
                 * should not have added anything to it.
                 */
                ASSERT(zsd_find(&zone->zone_zsd, zsdp->zsd_key) == NULL);

                t = kmem_zalloc(sizeof (*t), KM_SLEEP);
                t->zsd_key = zsdp->zsd_key;
                t->zsd_create = zsdp->zsd_create;
                t->zsd_shutdown = zsdp->zsd_shutdown;
                t->zsd_destroy = zsdp->zsd_destroy;
                if (zsdp->zsd_create != NULL) {
                        t->zsd_flags = ZSD_CREATE_NEEDED;
                        DTRACE_PROBE2(zsd__create__needed,
                            zone_t *, zone, zone_key_t, zsdp->zsd_key);
                }
                list_insert_tail(&zone->zone_zsd, t);
        }
        mutex_exit(&zsd_key_lock);
        mutex_exit(&zone->zone_lock);
}

enum zsd_callback_type { ZSD_CREATE, ZSD_SHUTDOWN, ZSD_DESTROY };

/*
 * Helper function to execute shutdown or destructor callbacks.
 */
static void
zone_zsd_callbacks(zone_t *zone, enum zsd_callback_type ct)
{
        struct zsd_entry *t;

        ASSERT(ct == ZSD_SHUTDOWN || ct == ZSD_DESTROY);
        ASSERT(ct != ZSD_SHUTDOWN || zone_status_get(zone) >= ZONE_IS_EMPTY);
        ASSERT(ct != ZSD_DESTROY || zone_status_get(zone) >= ZONE_IS_DOWN);

        /*
         * Run the callback solely based on what is registered for the zone
         * in zone_zsd. The global list can change independently of this
         * as keys are registered and unregistered and we don't register new
         * callbacks for a zone that is in the process of going away.
         */
        mutex_enter(&zone->zone_lock);
        for (t = list_head(&zone->zone_zsd); t != NULL;
            t = list_next(&zone->zone_zsd, t)) {
                zone_key_t key = t->zsd_key;

                /* Skip if no callbacks registered */

                if (ct == ZSD_SHUTDOWN) {
                        if (t->zsd_shutdown != NULL &&
                            (t->zsd_flags & ZSD_SHUTDOWN_ALL) == 0) {
                                t->zsd_flags |= ZSD_SHUTDOWN_NEEDED;
                                DTRACE_PROBE2(zsd__shutdown__needed,
                                    zone_t *, zone, zone_key_t, key);
                        }
                } else {
                        if (t->zsd_destroy != NULL &&
                            (t->zsd_flags & ZSD_DESTROY_ALL) == 0) {
                                t->zsd_flags |= ZSD_DESTROY_NEEDED;
                                DTRACE_PROBE2(zsd__destroy__needed,
                                    zone_t *, zone, zone_key_t, key);
                        }
                }
        }
        mutex_exit(&zone->zone_lock);

        /* Now call the shutdown and destroy callback for this key */
        zsd_apply_all_keys(zsd_apply_shutdown, zone);
        zsd_apply_all_keys(zsd_apply_destroy, zone);

}

/*
 * Called when the zone is going away; free ZSD-related memory, and
 * destroy the zone_zsd list.
 */
static void
zone_free_zsd(zone_t *zone)
{
        struct zsd_entry *t, *next;

        /*
         * Free all the zsd_entry's we had on this zone.
         */
        mutex_enter(&zone->zone_lock);
        for (t = list_head(&zone->zone_zsd); t != NULL; t = next) {
                next = list_next(&zone->zone_zsd, t);
                list_remove(&zone->zone_zsd, t);
                ASSERT(!(t->zsd_flags & ZSD_ALL_INPROGRESS));
                kmem_free(t, sizeof (*t));
        }
        list_destroy(&zone->zone_zsd);
        mutex_exit(&zone->zone_lock);

}

/*
 * Apply a function to all zones for particular key value.
 *
 * The applyfn has to drop zonehash_lock if it does some work, and
 * then reacquire it before it returns.
 * When the lock is dropped we don't follow list_next even
 * if it is possible to do so without any hazards. This is
 * because we want the design to allow for the list of zones
 * to change in any arbitrary way during the time the
 * lock was dropped.
 *
 * It is safe to restart the loop at list_head since the applyfn
 * changes the zsd_flags as it does work, so a subsequent
 * pass through will have no effect in applyfn, hence the loop will terminate
 * in at worst O(N^2).
 */
static void
zsd_apply_all_zones(zsd_applyfn_t *applyfn, zone_key_t key)
{
        zone_t *zone;

        mutex_enter(&zonehash_lock);
        zone = list_head(&zone_active);
        while (zone != NULL) {
                if ((applyfn)(&zonehash_lock, B_FALSE, zone, key)) {
                        /* Lock dropped - restart at head */
                        zone = list_head(&zone_active);
                } else {
                        zone = list_next(&zone_active, zone);
                }
        }
        mutex_exit(&zonehash_lock);
}

/*
 * Apply a function to all keys for a particular zone.
 *
 * The applyfn has to drop zonehash_lock if it does some work, and
 * then reacquire it before it returns.
 * When the lock is dropped we don't follow list_next even
 * if it is possible to do so without any hazards. This is
 * because we want the design to allow for the list of zsd callbacks
 * to change in any arbitrary way during the time the
 * lock was dropped.
 *
 * It is safe to restart the loop at list_head since the applyfn
 * changes the zsd_flags as it does work, so a subsequent
 * pass through will have no effect in applyfn, hence the loop will terminate
 * in at worst O(N^2).
 */
static void
zsd_apply_all_keys(zsd_applyfn_t *applyfn, zone_t *zone)
{
        struct zsd_entry *t;

        mutex_enter(&zone->zone_lock);
        t = list_head(&zone->zone_zsd);
        while (t != NULL) {
                if ((applyfn)(NULL, B_TRUE, zone, t->zsd_key)) {
                        /* Lock dropped - restart at head */
                        t = list_head(&zone->zone_zsd);
                } else {
                        t = list_next(&zone->zone_zsd, t);
                }
        }
        mutex_exit(&zone->zone_lock);
}

/*
 * Call the create function for the zone and key if CREATE_NEEDED
 * is set.
 * If some other thread gets here first and sets CREATE_INPROGRESS, then
 * we wait for that thread to complete so that we can ensure that
 * all the callbacks are done when we've looped over all zones/keys.
 *
 * When we call the create function, we drop the global held by the
 * caller, and return true to tell the caller it needs to re-evalute the
 * state.
 * If the caller holds zone_lock then zone_lock_held is set, and zone_lock
 * remains held on exit.
 */
static boolean_t
zsd_apply_create(kmutex_t *lockp, boolean_t zone_lock_held,
    zone_t *zone, zone_key_t key)
{
        void *result;
        struct zsd_entry *t;
        boolean_t dropped;

        if (lockp != NULL) {
                ASSERT(MUTEX_HELD(lockp));
        }
        if (zone_lock_held) {
                ASSERT(MUTEX_HELD(&zone->zone_lock));
        } else {
                mutex_enter(&zone->zone_lock);
        }

        t = zsd_find(&zone->zone_zsd, key);
        if (t == NULL) {
                /*
                 * Somebody else got here first e.g the zone going
                 * away.
                 */
                if (!zone_lock_held)
                        mutex_exit(&zone->zone_lock);
                return (B_FALSE);
        }
        dropped = B_FALSE;
        if (zsd_wait_for_inprogress(zone, t, lockp))
                dropped = B_TRUE;

        if (t->zsd_flags & ZSD_CREATE_NEEDED) {
                t->zsd_flags &= ~ZSD_CREATE_NEEDED;
                t->zsd_flags |= ZSD_CREATE_INPROGRESS;
                DTRACE_PROBE2(zsd__create__inprogress,
                    zone_t *, zone, zone_key_t, key);
                mutex_exit(&zone->zone_lock);
                if (lockp != NULL)
                        mutex_exit(lockp);

                dropped = B_TRUE;
                ASSERT(t->zsd_create != NULL);
                DTRACE_PROBE2(zsd__create__start,
                    zone_t *, zone, zone_key_t, key);

                result = (*t->zsd_create)(zone->zone_id);

                DTRACE_PROBE2(zsd__create__end,
                    zone_t *, zone, voidn *, result);

                ASSERT(result != NULL);
                if (lockp != NULL)
                        mutex_enter(lockp);
                mutex_enter(&zone->zone_lock);
                t->zsd_data = result;
                t->zsd_flags &= ~ZSD_CREATE_INPROGRESS;
                t->zsd_flags |= ZSD_CREATE_COMPLETED;
                cv_broadcast(&t->zsd_cv);
                DTRACE_PROBE2(zsd__create__completed,
                    zone_t *, zone, zone_key_t, key);
        }
        if (!zone_lock_held)
                mutex_exit(&zone->zone_lock);
        return (dropped);
}

/*
 * Call the shutdown function for the zone and key if SHUTDOWN_NEEDED
 * is set.
 * If some other thread gets here first and sets *_INPROGRESS, then
 * we wait for that thread to complete so that we can ensure that
 * all the callbacks are done when we've looped over all zones/keys.
 *
 * When we call the shutdown function, we drop the global held by the
 * caller, and return true to tell the caller it needs to re-evalute the
 * state.
 * If the caller holds zone_lock then zone_lock_held is set, and zone_lock
 * remains held on exit.
 */
static boolean_t
zsd_apply_shutdown(kmutex_t *lockp, boolean_t zone_lock_held,
    zone_t *zone, zone_key_t key)
{
        struct zsd_entry *t;
        void *data;
        boolean_t dropped;

        if (lockp != NULL) {
                ASSERT(MUTEX_HELD(lockp));
        }
        if (zone_lock_held) {
                ASSERT(MUTEX_HELD(&zone->zone_lock));
        } else {
                mutex_enter(&zone->zone_lock);
        }

        t = zsd_find(&zone->zone_zsd, key);
        if (t == NULL) {
                /*
                 * Somebody else got here first e.g the zone going
                 * away.
                 */
                if (!zone_lock_held)
                        mutex_exit(&zone->zone_lock);
                return (B_FALSE);
        }
        dropped = B_FALSE;
        if (zsd_wait_for_creator(zone, t, lockp))
                dropped = B_TRUE;

        if (zsd_wait_for_inprogress(zone, t, lockp))
                dropped = B_TRUE;

        if (t->zsd_flags & ZSD_SHUTDOWN_NEEDED) {
                t->zsd_flags &= ~ZSD_SHUTDOWN_NEEDED;
                t->zsd_flags |= ZSD_SHUTDOWN_INPROGRESS;
                DTRACE_PROBE2(zsd__shutdown__inprogress,
                    zone_t *, zone, zone_key_t, key);
                mutex_exit(&zone->zone_lock);
                if (lockp != NULL)
                        mutex_exit(lockp);
                dropped = B_TRUE;

                ASSERT(t->zsd_shutdown != NULL);
                data = t->zsd_data;

                DTRACE_PROBE2(zsd__shutdown__start,
                    zone_t *, zone, zone_key_t, key);

                (t->zsd_shutdown)(zone->zone_id, data);
                DTRACE_PROBE2(zsd__shutdown__end,
                    zone_t *, zone, zone_key_t, key);

                if (lockp != NULL)
                        mutex_enter(lockp);
                mutex_enter(&zone->zone_lock);
                t->zsd_flags &= ~ZSD_SHUTDOWN_INPROGRESS;
                t->zsd_flags |= ZSD_SHUTDOWN_COMPLETED;
                cv_broadcast(&t->zsd_cv);
                DTRACE_PROBE2(zsd__shutdown__completed,
                    zone_t *, zone, zone_key_t, key);
        }
        if (!zone_lock_held)
                mutex_exit(&zone->zone_lock);
        return (dropped);
}

/*
 * Call the destroy function for the zone and key if DESTROY_NEEDED
 * is set.
 * If some other thread gets here first and sets *_INPROGRESS, then
 * we wait for that thread to complete so that we can ensure that
 * all the callbacks are done when we've looped over all zones/keys.
 *
 * When we call the destroy function, we drop the global held by the
 * caller, and return true to tell the caller it needs to re-evalute the
 * state.
 * If the caller holds zone_lock then zone_lock_held is set, and zone_lock
 * remains held on exit.
 */
static boolean_t
zsd_apply_destroy(kmutex_t *lockp, boolean_t zone_lock_held,
    zone_t *zone, zone_key_t key)
{
        struct zsd_entry *t;
        void *data;
        boolean_t dropped;

        if (lockp != NULL) {
                ASSERT(MUTEX_HELD(lockp));
        }
        if (zone_lock_held) {
                ASSERT(MUTEX_HELD(&zone->zone_lock));
        } else {
                mutex_enter(&zone->zone_lock);
        }

        t = zsd_find(&zone->zone_zsd, key);
        if (t == NULL) {
                /*
                 * Somebody else got here first e.g the zone going
                 * away.
                 */
                if (!zone_lock_held)
                        mutex_exit(&zone->zone_lock);
                return (B_FALSE);
        }
        dropped = B_FALSE;
        if (zsd_wait_for_creator(zone, t, lockp))
                dropped = B_TRUE;

        if (zsd_wait_for_inprogress(zone, t, lockp))
                dropped = B_TRUE;

        if (t->zsd_flags & ZSD_DESTROY_NEEDED) {
                t->zsd_flags &= ~ZSD_DESTROY_NEEDED;
                t->zsd_flags |= ZSD_DESTROY_INPROGRESS;
                DTRACE_PROBE2(zsd__destroy__inprogress,
                    zone_t *, zone, zone_key_t, key);
                mutex_exit(&zone->zone_lock);
                if (lockp != NULL)
                        mutex_exit(lockp);
                dropped = B_TRUE;

                ASSERT(t->zsd_destroy != NULL);
                data = t->zsd_data;
                DTRACE_PROBE2(zsd__destroy__start,
                    zone_t *, zone, zone_key_t, key);

                (t->zsd_destroy)(zone->zone_id, data);
                DTRACE_PROBE2(zsd__destroy__end,
                    zone_t *, zone, zone_key_t, key);

                if (lockp != NULL)
                        mutex_enter(lockp);
                mutex_enter(&zone->zone_lock);
                t->zsd_data = NULL;
                t->zsd_flags &= ~ZSD_DESTROY_INPROGRESS;
                t->zsd_flags |= ZSD_DESTROY_COMPLETED;
                cv_broadcast(&t->zsd_cv);
                DTRACE_PROBE2(zsd__destroy__completed,
                    zone_t *, zone, zone_key_t, key);
        }
        if (!zone_lock_held)
                mutex_exit(&zone->zone_lock);
        return (dropped);
}

/*
 * Wait for any CREATE_NEEDED flag to be cleared.
 * Returns true if lockp was temporarily dropped while waiting.
 */
static boolean_t
zsd_wait_for_creator(zone_t *zone, struct zsd_entry *t, kmutex_t *lockp)
{
        boolean_t dropped = B_FALSE;

        while (t->zsd_flags & ZSD_CREATE_NEEDED) {
                DTRACE_PROBE2(zsd__wait__for__creator,
                    zone_t *, zone, struct zsd_entry *, t);
                if (lockp != NULL) {
                        dropped = B_TRUE;
                        mutex_exit(lockp);
                }
                cv_wait(&t->zsd_cv, &zone->zone_lock);
                if (lockp != NULL) {
                        /* First drop zone_lock to preserve order */
                        mutex_exit(&zone->zone_lock);
                        mutex_enter(lockp);
                        mutex_enter(&zone->zone_lock);
                }
        }
        return (dropped);
}

/*
 * Wait for any INPROGRESS flag to be cleared.
 * Returns true if lockp was temporarily dropped while waiting.
 */
static boolean_t
zsd_wait_for_inprogress(zone_t *zone, struct zsd_entry *t, kmutex_t *lockp)
{
        boolean_t dropped = B_FALSE;

        while (t->zsd_flags & ZSD_ALL_INPROGRESS) {
                DTRACE_PROBE2(zsd__wait__for__inprogress,
                    zone_t *, zone, struct zsd_entry *, t);
                if (lockp != NULL) {
                        dropped = B_TRUE;
                        mutex_exit(lockp);
                }
                cv_wait(&t->zsd_cv, &zone->zone_lock);
                if (lockp != NULL) {
                        /* First drop zone_lock to preserve order */
                        mutex_exit(&zone->zone_lock);
                        mutex_enter(lockp);
                        mutex_enter(&zone->zone_lock);
                }
        }
        return (dropped);
}

/*
 * Frees memory associated with the zone dataset list.
 */
static void
zone_free_datasets(zone_t *zone)
{
        zone_dataset_t *t, *next;

        for (t = list_head(&zone->zone_datasets); t != NULL; t = next) {
                next = list_next(&zone->zone_datasets, t);
                list_remove(&zone->zone_datasets, t);
                kmem_free(t->zd_dataset, strlen(t->zd_dataset) + 1);
                kmem_free(t, sizeof (*t));
        }
        list_destroy(&zone->zone_datasets);
}

/*
 * zone.cpu-shares resource control support.
 */
/*ARGSUSED*/
static rctl_qty_t
zone_cpu_shares_usage(rctl_t *rctl, struct proc *p)
{
        ASSERT(MUTEX_HELD(&p->p_lock));
        return (p->p_zone->zone_shares);
}

/*ARGSUSED*/
static int
zone_cpu_shares_set(rctl_t *rctl, struct proc *p, rctl_entity_p_t *e,
    rctl_qty_t nv)
{
        ASSERT(MUTEX_HELD(&p->p_lock));
        ASSERT(e->rcep_t == RCENTITY_ZONE);
        if (e->rcep_p.zone == NULL)
                return (0);

        e->rcep_p.zone->zone_shares = nv;
        return (0);
}

static rctl_ops_t zone_cpu_shares_ops = {
        rcop_no_action,
        zone_cpu_shares_usage,
        zone_cpu_shares_set,
        rcop_no_test
};

/*
 * zone.cpu-cap resource control support.
 */
/*ARGSUSED*/
static rctl_qty_t
zone_cpu_cap_get(rctl_t *rctl, struct proc *p)
{
        ASSERT(MUTEX_HELD(&p->p_lock));
        return (cpucaps_zone_get(p->p_zone));
}

/*ARGSUSED*/
static int
zone_cpu_cap_set(rctl_t *rctl, struct proc *p, rctl_entity_p_t *e,
    rctl_qty_t nv)
{
        zone_t *zone = e->rcep_p.zone;

        ASSERT(MUTEX_HELD(&p->p_lock));
        ASSERT(e->rcep_t == RCENTITY_ZONE);

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

        /*
         * set cap to the new value.
         */
        return (cpucaps_zone_set(zone, nv));
}

static rctl_ops_t zone_cpu_cap_ops = {
        rcop_no_action,
        zone_cpu_cap_get,
        zone_cpu_cap_set,
        rcop_no_test
};

/*ARGSUSED*/
static rctl_qty_t
zone_lwps_usage(rctl_t *r, proc_t *p)
{
        rctl_qty_t nlwps;
        zone_t *zone = p->p_zone;

        ASSERT(MUTEX_HELD(&p->p_lock));

        mutex_enter(&zone->zone_nlwps_lock);
        nlwps = zone->zone_nlwps;
        mutex_exit(&zone->zone_nlwps_lock);

        return (nlwps);
}

/*ARGSUSED*/
static int
zone_lwps_test(rctl_t *r, proc_t *p, rctl_entity_p_t *e, rctl_val_t *rcntl,
    rctl_qty_t incr, uint_t flags)
{
        rctl_qty_t nlwps;

        ASSERT(MUTEX_HELD(&p->p_lock));
        ASSERT(e->rcep_t == RCENTITY_ZONE);
        if (e->rcep_p.zone == NULL)
                return (0);
        ASSERT(MUTEX_HELD(&(e->rcep_p.zone->zone_nlwps_lock)));
        nlwps = e->rcep_p.zone->zone_nlwps;

        if (nlwps + incr > rcntl->rcv_value)
                return (1);

        return (0);
}

/*ARGSUSED*/
static int
zone_lwps_set(rctl_t *rctl, struct proc *p, rctl_entity_p_t *e, rctl_qty_t nv)
{
        ASSERT(MUTEX_HELD(&p->p_lock));
        ASSERT(e->rcep_t == RCENTITY_ZONE);
        if (e->rcep_p.zone == NULL)
                return (0);
        e->rcep_p.zone->zone_nlwps_ctl = nv;
        return (0);
}

static rctl_ops_t zone_lwps_ops = {
        rcop_no_action,
        zone_lwps_usage,
        zone_lwps_set,
        zone_lwps_test,
};

/*ARGSUSED*/
static rctl_qty_t
zone_procs_usage(rctl_t *r, proc_t *p)
{
        rctl_qty_t nprocs;
        zone_t *zone = p->p_zone;

        ASSERT(MUTEX_HELD(&p->p_lock));

        mutex_enter(&zone->zone_nlwps_lock);
        nprocs = zone->zone_nprocs;
        mutex_exit(&zone->zone_nlwps_lock);

        return (nprocs);
}

/*ARGSUSED*/
static int
zone_procs_test(rctl_t *r, proc_t *p, rctl_entity_p_t *e, rctl_val_t *rcntl,
    rctl_qty_t incr, uint_t flags)
{
        rctl_qty_t nprocs;

        ASSERT(MUTEX_HELD(&p->p_lock));
        ASSERT(e->rcep_t == RCENTITY_ZONE);
        if (e->rcep_p.zone == NULL)
                return (0);
        ASSERT(MUTEX_HELD(&(e->rcep_p.zone->zone_nlwps_lock)));
        nprocs = e->rcep_p.zone->zone_nprocs;

        if (nprocs + incr > rcntl->rcv_value)
                return (1);

        return (0);
}

/*ARGSUSED*/
static int
zone_procs_set(rctl_t *rctl, struct proc *p, rctl_entity_p_t *e, rctl_qty_t nv)
{
        ASSERT(MUTEX_HELD(&p->p_lock));
        ASSERT(e->rcep_t == RCENTITY_ZONE);
        if (e->rcep_p.zone == NULL)
                return (0);
        e->rcep_p.zone->zone_nprocs_ctl = nv;
        return (0);
}

static rctl_ops_t zone_procs_ops = {
        rcop_no_action,
        zone_procs_usage,
        zone_procs_set,
        zone_procs_test,
};

/*ARGSUSED*/
static rctl_qty_t
zone_shmmax_usage(rctl_t *rctl, struct proc *p)
{
        ASSERT(MUTEX_HELD(&p->p_lock));
        return (p->p_zone->zone_shmmax);
}

/*ARGSUSED*/
static int
zone_shmmax_test(rctl_t *r, proc_t *p, rctl_entity_p_t *e, rctl_val_t *rval,
    rctl_qty_t incr, uint_t flags)
{
        rctl_qty_t v;
        ASSERT(MUTEX_HELD(&p->p_lock));
        ASSERT(e->rcep_t == RCENTITY_ZONE);
        v = e->rcep_p.zone->zone_shmmax + incr;
        if (v > rval->rcv_value)
                return (1);
        return (0);
}

static rctl_ops_t zone_shmmax_ops = {
        rcop_no_action,
        zone_shmmax_usage,
        rcop_no_set,
        zone_shmmax_test
};

/*ARGSUSED*/
static rctl_qty_t
zone_shmmni_usage(rctl_t *rctl, struct proc *p)
{
        ASSERT(MUTEX_HELD(&p->p_lock));
        return (p->p_zone->zone_ipc.ipcq_shmmni);
}

/*ARGSUSED*/
static int
zone_shmmni_test(rctl_t *r, proc_t *p, rctl_entity_p_t *e, rctl_val_t *rval,
    rctl_qty_t incr, uint_t flags)
{
        rctl_qty_t v;
        ASSERT(MUTEX_HELD(&p->p_lock));
        ASSERT(e->rcep_t == RCENTITY_ZONE);
        v = e->rcep_p.zone->zone_ipc.ipcq_shmmni + incr;
        if (v > rval->rcv_value)
                return (1);
        return (0);
}

static rctl_ops_t zone_shmmni_ops = {
        rcop_no_action,
        zone_shmmni_usage,
        rcop_no_set,
        zone_shmmni_test
};

/*ARGSUSED*/
static rctl_qty_t
zone_semmni_usage(rctl_t *rctl, struct proc *p)
{
        ASSERT(MUTEX_HELD(&p->p_lock));
        return (p->p_zone->zone_ipc.ipcq_semmni);
}

/*ARGSUSED*/
static int
zone_semmni_test(rctl_t *r, proc_t *p, rctl_entity_p_t *e, rctl_val_t *rval,
    rctl_qty_t incr, uint_t flags)
{
        rctl_qty_t v;
        ASSERT(MUTEX_HELD(&p->p_lock));
        ASSERT(e->rcep_t == RCENTITY_ZONE);
        v = e->rcep_p.zone->zone_ipc.ipcq_semmni + incr;
        if (v > rval->rcv_value)
                return (1);
        return (0);
}

static rctl_ops_t zone_semmni_ops = {
        rcop_no_action,
        zone_semmni_usage,
        rcop_no_set,
        zone_semmni_test
};

/*ARGSUSED*/
static rctl_qty_t
zone_msgmni_usage(rctl_t *rctl, struct proc *p)
{
        ASSERT(MUTEX_HELD(&p->p_lock));
        return (p->p_zone->zone_ipc.ipcq_msgmni);
}

/*ARGSUSED*/
static int
zone_msgmni_test(rctl_t *r, proc_t *p, rctl_entity_p_t *e, rctl_val_t *rval,
    rctl_qty_t incr, uint_t flags)
{
        rctl_qty_t v;
        ASSERT(MUTEX_HELD(&p->p_lock));
        ASSERT(e->rcep_t == RCENTITY_ZONE);
        v = e->rcep_p.zone->zone_ipc.ipcq_msgmni + incr;
        if (v > rval->rcv_value)
                return (1);
        return (0);
}

static rctl_ops_t zone_msgmni_ops = {
        rcop_no_action,
        zone_msgmni_usage,
        rcop_no_set,
        zone_msgmni_test
};

/*ARGSUSED*/
static rctl_qty_t
zone_locked_mem_usage(rctl_t *rctl, struct proc *p)
{
        rctl_qty_t q;
        ASSERT(MUTEX_HELD(&p->p_lock));
        mutex_enter(&p->p_zone->zone_mem_lock);
        q = p->p_zone->zone_locked_mem;
        mutex_exit(&p->p_zone->zone_mem_lock);
        return (q);
}

/*ARGSUSED*/
static int
zone_locked_mem_test(rctl_t *r, proc_t *p, rctl_entity_p_t *e,
    rctl_val_t *rcntl, rctl_qty_t incr, uint_t flags)
{
        rctl_qty_t q;
        zone_t *z;

        z = e->rcep_p.zone;
        ASSERT(MUTEX_HELD(&p->p_lock));
        ASSERT(MUTEX_HELD(&z->zone_mem_lock));
        q = z->zone_locked_mem;
        if (q + incr > rcntl->rcv_value)
                return (1);
        return (0);
}

/*ARGSUSED*/
static int
zone_locked_mem_set(rctl_t *rctl, struct proc *p, rctl_entity_p_t *e,
    rctl_qty_t nv)
{
        ASSERT(MUTEX_HELD(&p->p_lock));
        ASSERT(e->rcep_t == RCENTITY_ZONE);
        if (e->rcep_p.zone == NULL)
                return (0);
        e->rcep_p.zone->zone_locked_mem_ctl = nv;
        return (0);
}

static rctl_ops_t zone_locked_mem_ops = {
        rcop_no_action,
        zone_locked_mem_usage,
        zone_locked_mem_set,
        zone_locked_mem_test
};

/*ARGSUSED*/
static rctl_qty_t
zone_max_swap_usage(rctl_t *rctl, struct proc *p)
{
        rctl_qty_t q;
        zone_t *z = p->p_zone;

        ASSERT(MUTEX_HELD(&p->p_lock));
        mutex_enter(&z->zone_mem_lock);
        q = z->zone_max_swap;
        mutex_exit(&z->zone_mem_lock);
        return (q);
}

/*ARGSUSED*/
static int
zone_max_swap_test(rctl_t *r, proc_t *p, rctl_entity_p_t *e,
    rctl_val_t *rcntl, rctl_qty_t incr, uint_t flags)
{
        rctl_qty_t q;
        zone_t *z;

        z = e->rcep_p.zone;
        ASSERT(MUTEX_HELD(&p->p_lock));
        ASSERT(MUTEX_HELD(&z->zone_mem_lock));
        q = z->zone_max_swap;
        if (q + incr > rcntl->rcv_value)
                return (1);
        return (0);
}

/*ARGSUSED*/
static int
zone_max_swap_set(rctl_t *rctl, struct proc *p, rctl_entity_p_t *e,
    rctl_qty_t nv)
{
        ASSERT(MUTEX_HELD(&p->p_lock));
        ASSERT(e->rcep_t == RCENTITY_ZONE);
        if (e->rcep_p.zone == NULL)
                return (0);
        e->rcep_p.zone->zone_max_swap_ctl = nv;
        return (0);
}

static rctl_ops_t zone_max_swap_ops = {
        rcop_no_action,
        zone_max_swap_usage,
        zone_max_swap_set,
        zone_max_swap_test
};

/*ARGSUSED*/
static rctl_qty_t
zone_max_lofi_usage(rctl_t *rctl, struct proc *p)
{
        rctl_qty_t q;
        zone_t *z = p->p_zone;

        ASSERT(MUTEX_HELD(&p->p_lock));
        mutex_enter(&z->zone_rctl_lock);
        q = z->zone_max_lofi;
        mutex_exit(&z->zone_rctl_lock);
        return (q);
}

/*ARGSUSED*/
static int
zone_max_lofi_test(rctl_t *r, proc_t *p, rctl_entity_p_t *e,
    rctl_val_t *rcntl, rctl_qty_t incr, uint_t flags)
{
        rctl_qty_t q;
        zone_t *z;

        z = e->rcep_p.zone;
        ASSERT(MUTEX_HELD(&p->p_lock));
        ASSERT(MUTEX_HELD(&z->zone_rctl_lock));
        q = z->zone_max_lofi;
        if (q + incr > rcntl->rcv_value)
                return (1);
        return (0);
}

/*ARGSUSED*/
static int
zone_max_lofi_set(rctl_t *rctl, struct proc *p, rctl_entity_p_t *e,
    rctl_qty_t nv)
{
        ASSERT(MUTEX_HELD(&p->p_lock));
        ASSERT(e->rcep_t == RCENTITY_ZONE);
        if (e->rcep_p.zone == NULL)
                return (0);
        e->rcep_p.zone->zone_max_lofi_ctl = nv;
        return (0);
}

static rctl_ops_t zone_max_lofi_ops = {
        rcop_no_action,
        zone_max_lofi_usage,
        zone_max_lofi_set,
        zone_max_lofi_test
};

/*
 * Helper function to brand the zone with a unique ID.
 */
static void
zone_uniqid(zone_t *zone)
{
        static uint64_t uniqid = 0;

        ASSERT(MUTEX_HELD(&zonehash_lock));
        zone->zone_uniqid = uniqid++;
}

/*
 * Returns a held pointer to the "kcred" for the specified zone.
 */
struct cred *
zone_get_kcred(zoneid_t zoneid)
{
        zone_t *zone;
        cred_t *cr;

        if ((zone = zone_find_by_id(zoneid)) == NULL)
                return (NULL);
        cr = zone->zone_kcred;
        crhold(cr);
        zone_rele(zone);
        return (cr);
}

static int
zone_lockedmem_kstat_update(kstat_t *ksp, int rw)
{
        zone_t *zone = ksp->ks_private;
        zone_kstat_t *zk = ksp->ks_data;

        if (rw == KSTAT_WRITE)
                return (EACCES);

        zk->zk_usage.value.ui64 = zone->zone_locked_mem;
        zk->zk_value.value.ui64 = zone->zone_locked_mem_ctl;
        return (0);
}

static int
zone_nprocs_kstat_update(kstat_t *ksp, int rw)
{
        zone_t *zone = ksp->ks_private;
        zone_kstat_t *zk = ksp->ks_data;

        if (rw == KSTAT_WRITE)
                return (EACCES);

        zk->zk_usage.value.ui64 = zone->zone_nprocs;
        zk->zk_value.value.ui64 = zone->zone_nprocs_ctl;
        return (0);
}

static int
zone_swapresv_kstat_update(kstat_t *ksp, int rw)
{
        zone_t *zone = ksp->ks_private;
        zone_kstat_t *zk = ksp->ks_data;

        if (rw == KSTAT_WRITE)
                return (EACCES);

        zk->zk_usage.value.ui64 = zone->zone_max_swap;
        zk->zk_value.value.ui64 = zone->zone_max_swap_ctl;
        return (0);
}

static kstat_t *
zone_kstat_create_common(zone_t *zone, char *name,
    int (*updatefunc) (kstat_t *, int))
{
        kstat_t *ksp;
        zone_kstat_t *zk;

        ksp = rctl_kstat_create_zone(zone, name, KSTAT_TYPE_NAMED,
            sizeof (zone_kstat_t) / sizeof (kstat_named_t),
            KSTAT_FLAG_VIRTUAL);

        if (ksp == NULL)
                return (NULL);

        zk = ksp->ks_data = kmem_alloc(sizeof (zone_kstat_t), KM_SLEEP);
        ksp->ks_data_size += strlen(zone->zone_name) + 1;
        kstat_named_init(&zk->zk_zonename, "zonename", KSTAT_DATA_STRING);
        kstat_named_setstr(&zk->zk_zonename, zone->zone_name);
        kstat_named_init(&zk->zk_usage, "usage", KSTAT_DATA_UINT64);
        kstat_named_init(&zk->zk_value, "value", KSTAT_DATA_UINT64);
        ksp->ks_update = updatefunc;
        ksp->ks_private = zone;
        kstat_install(ksp);
        return (ksp);
}


static int
zone_mcap_kstat_update(kstat_t *ksp, int rw)
{
        zone_t *zone = ksp->ks_private;
        zone_mcap_kstat_t *zmp = ksp->ks_data;

        if (rw == KSTAT_WRITE)
                return (EACCES);

        zmp->zm_pgpgin.value.ui64 = zone->zone_pgpgin;
        zmp->zm_anonpgin.value.ui64 = zone->zone_anonpgin;
        zmp->zm_execpgin.value.ui64 = zone->zone_execpgin;
        zmp->zm_fspgin.value.ui64 = zone->zone_fspgin;
        zmp->zm_anon_alloc_fail.value.ui64 = zone->zone_anon_alloc_fail;

        return (0);
}

static kstat_t *
zone_mcap_kstat_create(zone_t *zone)
{
        kstat_t *ksp;
        zone_mcap_kstat_t *zmp;

        if ((ksp = kstat_create_zone("memory_cap", zone->zone_id,
            zone->zone_name, "zone_memory_cap", KSTAT_TYPE_NAMED,
            sizeof (zone_mcap_kstat_t) / sizeof (kstat_named_t),
            KSTAT_FLAG_VIRTUAL, zone->zone_id)) == NULL)
                return (NULL);

        if (zone->zone_id != GLOBAL_ZONEID)
                kstat_zone_add(ksp, GLOBAL_ZONEID);

        zmp = ksp->ks_data = kmem_zalloc(sizeof (zone_mcap_kstat_t), KM_SLEEP);
        ksp->ks_data_size += strlen(zone->zone_name) + 1;
        ksp->ks_lock = &zone->zone_mcap_lock;
        zone->zone_mcap_stats = zmp;

        /* The kstat "name" field is not large enough for a full zonename */
        kstat_named_init(&zmp->zm_zonename, "zonename", KSTAT_DATA_STRING);
        kstat_named_setstr(&zmp->zm_zonename, zone->zone_name);
        kstat_named_init(&zmp->zm_pgpgin, "pgpgin", KSTAT_DATA_UINT64);
        kstat_named_init(&zmp->zm_anonpgin, "anonpgin", KSTAT_DATA_UINT64);
        kstat_named_init(&zmp->zm_execpgin, "execpgin", KSTAT_DATA_UINT64);
        kstat_named_init(&zmp->zm_fspgin, "fspgin", KSTAT_DATA_UINT64);
        kstat_named_init(&zmp->zm_anon_alloc_fail, "anon_alloc_fail",
            KSTAT_DATA_UINT64);

        ksp->ks_update = zone_mcap_kstat_update;
        ksp->ks_private = zone;

        kstat_install(ksp);
        return (ksp);
}

static int
zone_misc_kstat_update(kstat_t *ksp, int rw)
{
        zone_t *zone = ksp->ks_private;
        zone_misc_kstat_t *zmp = ksp->ks_data;
        hrtime_t tmp;

        if (rw == KSTAT_WRITE)
                return (EACCES);

        tmp = zone->zone_utime;
        scalehrtime(&tmp);
        zmp->zm_utime.value.ui64 = tmp;
        tmp = zone->zone_stime;
        scalehrtime(&tmp);
        zmp->zm_stime.value.ui64 = tmp;
        tmp = zone->zone_wtime;
        scalehrtime(&tmp);
        zmp->zm_wtime.value.ui64 = tmp;

        zmp->zm_avenrun1.value.ui32 = zone->zone_avenrun[0];
        zmp->zm_avenrun5.value.ui32 = zone->zone_avenrun[1];
        zmp->zm_avenrun15.value.ui32 = zone->zone_avenrun[2];

        zmp->zm_ffcap.value.ui32 = zone->zone_ffcap;
        zmp->zm_ffnoproc.value.ui32 = zone->zone_ffnoproc;
        zmp->zm_ffnomem.value.ui32 = zone->zone_ffnomem;
        zmp->zm_ffmisc.value.ui32 = zone->zone_ffmisc;

        zmp->zm_nested_intp.value.ui32 = zone->zone_nested_intp;

        zmp->zm_init_pid.value.ui32 = zone->zone_proc_initpid;
        zmp->zm_boot_time.value.ui64 = (uint64_t)zone->zone_boot_time;

        return (0);
}

static kstat_t *
zone_misc_kstat_create(zone_t *zone)
{
        kstat_t *ksp;
        zone_misc_kstat_t *zmp;

        if ((ksp = kstat_create_zone("zones", zone->zone_id,
            zone->zone_name, "zone_misc", KSTAT_TYPE_NAMED,
            sizeof (zone_misc_kstat_t) / sizeof (kstat_named_t),
            KSTAT_FLAG_VIRTUAL, zone->zone_id)) == NULL)
                return (NULL);

        if (zone->zone_id != GLOBAL_ZONEID)
                kstat_zone_add(ksp, GLOBAL_ZONEID);

        zmp = ksp->ks_data = kmem_zalloc(sizeof (zone_misc_kstat_t), KM_SLEEP);
        ksp->ks_data_size += strlen(zone->zone_name) + 1;
        ksp->ks_lock = &zone->zone_misc_lock;
        zone->zone_misc_stats = zmp;

        /* The kstat "name" field is not large enough for a full zonename */
        kstat_named_init(&zmp->zm_zonename, "zonename", KSTAT_DATA_STRING);
        kstat_named_setstr(&zmp->zm_zonename, zone->zone_name);
        kstat_named_init(&zmp->zm_utime, "nsec_user", KSTAT_DATA_UINT64);
        kstat_named_init(&zmp->zm_stime, "nsec_sys", KSTAT_DATA_UINT64);
        kstat_named_init(&zmp->zm_wtime, "nsec_waitrq", KSTAT_DATA_UINT64);
        kstat_named_init(&zmp->zm_avenrun1, "avenrun_1min", KSTAT_DATA_UINT32);
        kstat_named_init(&zmp->zm_avenrun5, "avenrun_5min", KSTAT_DATA_UINT32);
        kstat_named_init(&zmp->zm_avenrun15, "avenrun_15min",
            KSTAT_DATA_UINT32);
        kstat_named_init(&zmp->zm_ffcap, "forkfail_cap", KSTAT_DATA_UINT32);
        kstat_named_init(&zmp->zm_ffnoproc, "forkfail_noproc",
            KSTAT_DATA_UINT32);
        kstat_named_init(&zmp->zm_ffnomem, "forkfail_nomem", KSTAT_DATA_UINT32);
        kstat_named_init(&zmp->zm_ffmisc, "forkfail_misc", KSTAT_DATA_UINT32);
        kstat_named_init(&zmp->zm_nested_intp, "nested_interp",
            KSTAT_DATA_UINT32);
        kstat_named_init(&zmp->zm_init_pid, "init_pid", KSTAT_DATA_UINT32);
        kstat_named_init(&zmp->zm_boot_time, "boot_time", KSTAT_DATA_UINT64);

        ksp->ks_update = zone_misc_kstat_update;
        ksp->ks_private = zone;

        kstat_install(ksp);
        return (ksp);
}

static void
zone_kstat_create(zone_t *zone)
{
        zone->zone_lockedmem_kstat = zone_kstat_create_common(zone,
            "lockedmem", zone_lockedmem_kstat_update);
        zone->zone_swapresv_kstat = zone_kstat_create_common(zone,
            "swapresv", zone_swapresv_kstat_update);
        zone->zone_nprocs_kstat = zone_kstat_create_common(zone,
            "nprocs", zone_nprocs_kstat_update);

        if ((zone->zone_mcap_ksp = zone_mcap_kstat_create(zone)) == NULL) {
                zone->zone_mcap_stats = kmem_zalloc(
                    sizeof (zone_mcap_kstat_t), KM_SLEEP);
        }

        if ((zone->zone_misc_ksp = zone_misc_kstat_create(zone)) == NULL) {
                zone->zone_misc_stats = kmem_zalloc(
                    sizeof (zone_misc_kstat_t), KM_SLEEP);
        }
}

static void
zone_kstat_delete_common(kstat_t **pkstat, size_t datasz)
{
        void *data;

        if (*pkstat != NULL) {
                data = (*pkstat)->ks_data;
                kstat_delete(*pkstat);
                kmem_free(data, datasz);
                *pkstat = NULL;
        }
}

static void
zone_kstat_delete(zone_t *zone)
{
        zone_kstat_delete_common(&zone->zone_lockedmem_kstat,
            sizeof (zone_kstat_t));
        zone_kstat_delete_common(&zone->zone_swapresv_kstat,
            sizeof (zone_kstat_t));
        zone_kstat_delete_common(&zone->zone_nprocs_kstat,
            sizeof (zone_kstat_t));
        zone_kstat_delete_common(&zone->zone_mcap_ksp,
            sizeof (zone_mcap_kstat_t));
        zone_kstat_delete_common(&zone->zone_misc_ksp,
            sizeof (zone_misc_kstat_t));
}

/*
 * Called very early on in boot to initialize the ZSD list so that
 * zone_key_create() can be called before zone_init().  It also initializes
 * portions of zone0 which may be used before zone_init() is called.  The
 * variable "global_zone" will be set when zone0 is fully initialized by
 * zone_init().
 */
void
zone_zsd_init(void)
{
        mutex_init(&zonehash_lock, NULL, MUTEX_DEFAULT, NULL);
        mutex_init(&zsd_key_lock, NULL, MUTEX_DEFAULT, NULL);
        list_create(&zsd_registered_keys, sizeof (struct zsd_entry),
            offsetof(struct zsd_entry, zsd_linkage));
        list_create(&zone_active, sizeof (zone_t),
            offsetof(zone_t, zone_linkage));
        list_create(&zone_deathrow, sizeof (zone_t),
            offsetof(zone_t, zone_linkage));

        mutex_init(&zone0.zone_lock, NULL, MUTEX_DEFAULT, NULL);
        mutex_init(&zone0.zone_nlwps_lock, NULL, MUTEX_DEFAULT, NULL);
        mutex_init(&zone0.zone_mem_lock, NULL, MUTEX_DEFAULT, NULL);
        zone0.zone_shares = 1;
        zone0.zone_nlwps = 0;
        zone0.zone_nlwps_ctl = INT_MAX;
        zone0.zone_nprocs = 0;
        zone0.zone_nprocs_ctl = INT_MAX;
        zone0.zone_locked_mem = 0;
        zone0.zone_locked_mem_ctl = UINT64_MAX;
        ASSERT(zone0.zone_max_swap == 0);
        zone0.zone_max_swap_ctl = UINT64_MAX;
        zone0.zone_max_lofi = 0;
        zone0.zone_max_lofi_ctl = UINT64_MAX;
        zone0.zone_shmmax = 0;
        zone0.zone_ipc.ipcq_shmmni = 0;
        zone0.zone_ipc.ipcq_semmni = 0;
        zone0.zone_ipc.ipcq_msgmni = 0;
        zone0.zone_name = GLOBAL_ZONENAME;
        zone0.zone_nodename = utsname.nodename;
        zone0.zone_domain = srpc_domain;
        zone0.zone_hostid = HW_INVALID_HOSTID;
        zone0.zone_fs_allowed = NULL;
        psecflags_default(&zone0.zone_secflags);
        zone0.zone_ref = 1;
        zone0.zone_id = GLOBAL_ZONEID;
        zone0.zone_status = ZONE_IS_RUNNING;
        zone0.zone_rootpath = "/";
        zone0.zone_rootpathlen = 2;
        zone0.zone_psetid = ZONE_PS_INVAL;
        zone0.zone_ncpus = 0;
        zone0.zone_ncpus_online = 0;
        zone0.zone_proc_initpid = 1;
        zone0.zone_initname = initname;
        zone0.zone_lockedmem_kstat = NULL;
        zone0.zone_swapresv_kstat = NULL;
        zone0.zone_nprocs_kstat = NULL;

        zone0.zone_stime = 0;
        zone0.zone_utime = 0;
        zone0.zone_wtime = 0;

        list_create(&zone0.zone_ref_list, sizeof (zone_ref_t),
            offsetof(zone_ref_t, zref_linkage));
        list_create(&zone0.zone_zsd, sizeof (struct zsd_entry),
            offsetof(struct zsd_entry, zsd_linkage));
        list_insert_head(&zone_active, &zone0);

        /*
         * The root filesystem is not mounted yet, so zone_rootvp cannot be set
         * to anything meaningful.  It is assigned to be 'rootdir' in
         * vfs_mountroot().
         */
        zone0.zone_rootvp = NULL;
        zone0.zone_vfslist = NULL;
        zone0.zone_bootargs = initargs;
        zone0.zone_privset = kmem_alloc(sizeof (priv_set_t), KM_SLEEP);
        /*
         * The global zone has all privileges
         */
        priv_fillset(zone0.zone_privset);
        /*
         * Add p0 to the global zone
         */
        zone0.zone_zsched = &p0;
        p0.p_zone = &zone0;
}

/*
 * Called by main() to initialize the zones framework.
 */
void
zone_init(void)
{
        rctl_dict_entry_t *rde;
        rctl_val_t *dval;
        rctl_set_t *set;
        rctl_alloc_gp_t *gp;
        rctl_entity_p_t e;
        int res;

        ASSERT(curproc == &p0);

        /*
         * Create ID space for zone IDs.  ID 0 is reserved for the
         * global zone.
         */
        zoneid_space = id_space_create("zoneid_space", 1, MAX_ZONEID);

        /*
         * Initialize generic zone resource controls, if any.
         */
        rc_zone_cpu_shares = rctl_register("zone.cpu-shares",
            RCENTITY_ZONE, RCTL_GLOBAL_SIGNAL_NEVER | RCTL_GLOBAL_DENY_NEVER |
            RCTL_GLOBAL_NOBASIC | RCTL_GLOBAL_COUNT | RCTL_GLOBAL_SYSLOG_NEVER,
            FSS_MAXSHARES, FSS_MAXSHARES, &zone_cpu_shares_ops);

        rc_zone_cpu_cap = rctl_register("zone.cpu-cap",
            RCENTITY_ZONE, RCTL_GLOBAL_SIGNAL_NEVER | RCTL_GLOBAL_DENY_ALWAYS |
            RCTL_GLOBAL_NOBASIC | RCTL_GLOBAL_COUNT |RCTL_GLOBAL_SYSLOG_NEVER |
            RCTL_GLOBAL_INFINITE,
            MAXCAP, MAXCAP, &zone_cpu_cap_ops);

        rc_zone_nlwps = rctl_register("zone.max-lwps", RCENTITY_ZONE,
            RCTL_GLOBAL_NOACTION | RCTL_GLOBAL_NOBASIC | RCTL_GLOBAL_COUNT,
            INT_MAX, INT_MAX, &zone_lwps_ops);

        rc_zone_nprocs = rctl_register("zone.max-processes", RCENTITY_ZONE,
            RCTL_GLOBAL_NOACTION | RCTL_GLOBAL_NOBASIC | RCTL_GLOBAL_COUNT,
            INT_MAX, INT_MAX, &zone_procs_ops);

        /*
         * System V IPC resource controls
         */
        rc_zone_msgmni = rctl_register("zone.max-msg-ids",
            RCENTITY_ZONE, RCTL_GLOBAL_DENY_ALWAYS | RCTL_GLOBAL_NOBASIC |
            RCTL_GLOBAL_COUNT, IPC_IDS_MAX, IPC_IDS_MAX, &zone_msgmni_ops);

        rc_zone_semmni = rctl_register("zone.max-sem-ids",
            RCENTITY_ZONE, RCTL_GLOBAL_DENY_ALWAYS | RCTL_GLOBAL_NOBASIC |
            RCTL_GLOBAL_COUNT, IPC_IDS_MAX, IPC_IDS_MAX, &zone_semmni_ops);

        rc_zone_shmmni = rctl_register("zone.max-shm-ids",
            RCENTITY_ZONE, RCTL_GLOBAL_DENY_ALWAYS | RCTL_GLOBAL_NOBASIC |
            RCTL_GLOBAL_COUNT, IPC_IDS_MAX, IPC_IDS_MAX, &zone_shmmni_ops);

        rc_zone_shmmax = rctl_register("zone.max-shm-memory",
            RCENTITY_ZONE, RCTL_GLOBAL_DENY_ALWAYS | RCTL_GLOBAL_NOBASIC |
            RCTL_GLOBAL_BYTES, UINT64_MAX, UINT64_MAX, &zone_shmmax_ops);

        /*
         * Create a rctl_val with PRIVILEGED, NOACTION, value = 1.  Then attach
         * this at the head of the rctl_dict_entry for ``zone.cpu-shares''.
         */
        dval = kmem_cache_alloc(rctl_val_cache, KM_SLEEP);
        bzero(dval, sizeof (rctl_val_t));
        dval->rcv_value = 1;
        dval->rcv_privilege = RCPRIV_PRIVILEGED;
        dval->rcv_flagaction = RCTL_LOCAL_NOACTION;
        dval->rcv_action_recip_pid = -1;

        rde = rctl_dict_lookup("zone.cpu-shares");
        (void) rctl_val_list_insert(&rde->rcd_default_value, dval);

        rc_zone_locked_mem = rctl_register("zone.max-locked-memory",
            RCENTITY_ZONE, RCTL_GLOBAL_NOBASIC | RCTL_GLOBAL_BYTES |
            RCTL_GLOBAL_DENY_ALWAYS, UINT64_MAX, UINT64_MAX,
            &zone_locked_mem_ops);

        rc_zone_max_swap = rctl_register("zone.max-swap",
            RCENTITY_ZONE, RCTL_GLOBAL_NOBASIC | RCTL_GLOBAL_BYTES |
            RCTL_GLOBAL_DENY_ALWAYS, UINT64_MAX, UINT64_MAX,
            &zone_max_swap_ops);

        rc_zone_max_lofi = rctl_register("zone.max-lofi",
            RCENTITY_ZONE, RCTL_GLOBAL_NOBASIC | RCTL_GLOBAL_COUNT |
            RCTL_GLOBAL_DENY_ALWAYS, UINT64_MAX, UINT64_MAX,
            &zone_max_lofi_ops);

        /*
         * Initialize the ``global zone''.
         */
        set = rctl_set_create();
        gp = rctl_set_init_prealloc(RCENTITY_ZONE);
        mutex_enter(&p0.p_lock);
        e.rcep_p.zone = &zone0;
        e.rcep_t = RCENTITY_ZONE;
        zone0.zone_rctls = rctl_set_init(RCENTITY_ZONE, &p0, &e, set,
            gp);

        zone0.zone_nlwps = p0.p_lwpcnt;
        zone0.zone_nprocs = 1;
        zone0.zone_ntasks = 1;
        mutex_exit(&p0.p_lock);
        zone0.zone_restart_init = B_TRUE;
        zone0.zone_brand = &native_brand;
        rctl_prealloc_destroy(gp);
        /*
         * pool_default hasn't been initialized yet, so we let pool_init()
         * take care of making sure the global zone is in the default pool.
         */

        /*
         * Initialize global zone kstats
         */
        zone_kstat_create(&zone0);

        /*
         * Initialise the lock for the database structure used by mntfs.
         */
        rw_init(&zone0.zone_mntfs_db_lock, NULL, RW_DEFAULT, NULL);

        mutex_enter(&zonehash_lock);
        zone_uniqid(&zone0);
        ASSERT(zone0.zone_uniqid == GLOBAL_ZONEUNIQID);

        zonehashbyid = mod_hash_create_idhash("zone_by_id", zone_hash_size,
            mod_hash_null_valdtor);
        zonehashbyname = mod_hash_create_strhash("zone_by_name",
            zone_hash_size, mod_hash_null_valdtor);
        zonecount = 1;

        (void) mod_hash_insert(zonehashbyid, (mod_hash_key_t)GLOBAL_ZONEID,
            (mod_hash_val_t)&zone0);
        (void) mod_hash_insert(zonehashbyname, (mod_hash_key_t)zone0.zone_name,
            (mod_hash_val_t)&zone0);
        mutex_exit(&zonehash_lock);

        /*
         * We avoid setting zone_kcred until now, since kcred is initialized
         * sometime after zone_zsd_init() and before zone_init().
         */
        zone0.zone_kcred = kcred;
        /*
         * The global zone is fully initialized (except for zone_rootvp which
         * will be set when the root filesystem is mounted).
         */
        global_zone = &zone0;

        /*
         * Setup an event channel to send zone status change notifications on
         */
        res = sysevent_evc_bind(ZONE_EVENT_CHANNEL, &zone_event_chan,
            EVCH_CREAT);

        if (res)
                panic("Sysevent_evc_bind failed during zone setup.\n");

}

static void
zone_free(zone_t *zone)
{
        ASSERT(zone != global_zone);
        ASSERT(zone->zone_ntasks == 0);
        ASSERT(zone->zone_nlwps == 0);
        ASSERT(zone->zone_nprocs == 0);
        ASSERT(zone->zone_cred_ref == 0);
        ASSERT(zone->zone_kcred == NULL);
        ASSERT(zone_status_get(zone) == ZONE_IS_DEAD ||
            zone_status_get(zone) == ZONE_IS_UNINITIALIZED);
        ASSERT(list_is_empty(&zone->zone_ref_list));

        /*
         * Remove any zone caps.
         */
        cpucaps_zone_remove(zone);

        ASSERT(zone->zone_cpucap == NULL);

        /* remove from deathrow list */
        if (zone_status_get(zone) == ZONE_IS_DEAD) {
                ASSERT(zone->zone_ref == 0);
                mutex_enter(&zone_deathrow_lock);
                list_remove(&zone_deathrow, zone);
                mutex_exit(&zone_deathrow_lock);
        }

        list_destroy(&zone->zone_ref_list);
        zone_free_zsd(zone);
        zone_free_datasets(zone);
        list_destroy(&zone->zone_dl_list);

        if (zone->zone_rootvp != NULL)
                VN_RELE(zone->zone_rootvp);
        if (zone->zone_rootpath)
                kmem_free(zone->zone_rootpath, zone->zone_rootpathlen);
        if (zone->zone_name != NULL)
                kmem_free(zone->zone_name, ZONENAME_MAX);
        if (zone->zone_nodename != NULL)
                kmem_free(zone->zone_nodename, _SYS_NMLN);
        if (zone->zone_domain != NULL)
                kmem_free(zone->zone_domain, _SYS_NMLN);
        if (zone->zone_privset != NULL)
                kmem_free(zone->zone_privset, sizeof (priv_set_t));
        if (zone->zone_rctls != NULL)
                rctl_set_free(zone->zone_rctls);
        if (zone->zone_bootargs != NULL)
                strfree(zone->zone_bootargs);
        if (zone->zone_initname != NULL)
                strfree(zone->zone_initname);
        if (zone->zone_fs_allowed != NULL)
                strfree(zone->zone_fs_allowed);
        if (zone->zone_pfexecd != NULL)
                klpd_freelist(&zone->zone_pfexecd);
        id_free(zoneid_space, zone->zone_id);
        mutex_destroy(&zone->zone_lock);
        cv_destroy(&zone->zone_cv);
        rw_destroy(&zone->zone_mntfs_db_lock);
        kmem_free(zone, sizeof (zone_t));
}

/*
 * See block comment at the top of this file for information about zone
 * status values.
 */
/*
 * Convenience function for setting zone status.
 */
static void
zone_status_set(zone_t *zone, zone_status_t status)
{

        nvlist_t *nvl = NULL;
        ASSERT(MUTEX_HELD(&zone_status_lock));
        ASSERT(status > ZONE_MIN_STATE && status <= ZONE_MAX_STATE &&
            status >= zone_status_get(zone));

        if (nvlist_alloc(&nvl, NV_UNIQUE_NAME, KM_SLEEP) ||
            nvlist_add_string(nvl, ZONE_CB_NAME, zone->zone_name) ||
            nvlist_add_string(nvl, ZONE_CB_NEWSTATE,
            zone_status_table[status]) ||
            nvlist_add_string(nvl, ZONE_CB_OLDSTATE,
            zone_status_table[zone->zone_status]) ||
            nvlist_add_int32(nvl, ZONE_CB_ZONEID, zone->zone_id) ||
            nvlist_add_uint64(nvl, ZONE_CB_TIMESTAMP, (uint64_t)gethrtime()) ||
            sysevent_evc_publish(zone_event_chan, ZONE_EVENT_STATUS_CLASS,
            ZONE_EVENT_STATUS_SUBCLASS, "sun.com", "kernel", nvl, EVCH_SLEEP)) {
#ifdef DEBUG
                (void) printf(
                    "Failed to allocate and send zone state change event.\n");
#endif
        }
        nvlist_free(nvl);

        zone->zone_status = status;

        cv_broadcast(&zone->zone_cv);
}

/*
 * Public function to retrieve the zone status.  The zone status may
 * change after it is retrieved.
 */
zone_status_t
zone_status_get(zone_t *zone)
{
        return (zone->zone_status);
}

static int
zone_set_bootargs(zone_t *zone, const char *zone_bootargs)
{
        char *buf = kmem_zalloc(BOOTARGS_MAX, KM_SLEEP);
        int err = 0;

        ASSERT(zone != global_zone);
        if ((err = copyinstr(zone_bootargs, buf, BOOTARGS_MAX, NULL)) != 0)
                goto done;      /* EFAULT or ENAMETOOLONG */

        if (zone->zone_bootargs != NULL)
                strfree(zone->zone_bootargs);

        zone->zone_bootargs = strdup(buf);

done:
        kmem_free(buf, BOOTARGS_MAX);
        return (err);
}

static int
zone_set_brand(zone_t *zone, const char *brand)
{
        struct brand_attr *attrp;
        brand_t *bp;

        attrp = kmem_alloc(sizeof (struct brand_attr), KM_SLEEP);
        if (copyin(brand, attrp, sizeof (struct brand_attr)) != 0) {
                kmem_free(attrp, sizeof (struct brand_attr));
                return (EFAULT);
        }

        bp = brand_register_zone(attrp);
        kmem_free(attrp, sizeof (struct brand_attr));
        if (bp == NULL)
                return (EINVAL);

        /*
         * This is the only place where a zone can change it's brand.
         * We already need to hold zone_status_lock to check the zone
         * status, so we'll just use that lock to serialize zone
         * branding requests as well.
         */
        mutex_enter(&zone_status_lock);

        /* Re-Branding is not allowed and the zone can't be booted yet */
        if ((ZONE_IS_BRANDED(zone)) ||
            (zone_status_get(zone) >= ZONE_IS_BOOTING)) {
                mutex_exit(&zone_status_lock);
                brand_unregister_zone(bp);
                return (EINVAL);
        }

        /* set up the brand specific data */
        zone->zone_brand = bp;
        ZBROP(zone)->b_init_brand_data(zone);

        mutex_exit(&zone_status_lock);
        return (0);
}

static int
zone_set_secflags(zone_t *zone, const psecflags_t *zone_secflags)
{
        int err = 0;
        psecflags_t psf;

        ASSERT(zone != global_zone);

        if ((err = copyin(zone_secflags, &psf, sizeof (psf))) != 0)
                return (err);

        if (zone_status_get(zone) > ZONE_IS_READY)
                return (EINVAL);

        if (!psecflags_validate(&psf))
                return (EINVAL);

        (void) memcpy(&zone->zone_secflags, &psf, sizeof (psf));

        /* Set security flags on the zone's zsched */
        (void) memcpy(&zone->zone_zsched->p_secflags, &zone->zone_secflags,
            sizeof (zone->zone_zsched->p_secflags));

        return (0);
}

static int
zone_set_fs_allowed(zone_t *zone, const char *zone_fs_allowed)
{
        char *buf = kmem_zalloc(ZONE_FS_ALLOWED_MAX, KM_SLEEP);
        int err = 0;

        ASSERT(zone != global_zone);
        if ((err = copyinstr(zone_fs_allowed, buf,
            ZONE_FS_ALLOWED_MAX, NULL)) != 0)
                goto done;

        if (zone->zone_fs_allowed != NULL)
                strfree(zone->zone_fs_allowed);

        zone->zone_fs_allowed = strdup(buf);

done:
        kmem_free(buf, ZONE_FS_ALLOWED_MAX);
        return (err);
}

static int
zone_set_initname(zone_t *zone, const char *zone_initname)
{
        char initname[INITNAME_SZ];
        size_t len;
        int err = 0;

        ASSERT(zone != global_zone);
        if ((err = copyinstr(zone_initname, initname, INITNAME_SZ, &len)) != 0)
                return (err);   /* EFAULT or ENAMETOOLONG */

        if (zone->zone_initname != NULL)
                strfree(zone->zone_initname);

        zone->zone_initname = kmem_alloc(strlen(initname) + 1, KM_SLEEP);
        (void) strcpy(zone->zone_initname, initname);
        return (0);
}

static int
zone_set_phys_mcap(zone_t *zone, const uint64_t *zone_mcap)
{
        uint64_t mcap;
        int err = 0;

        if ((err = copyin(zone_mcap, &mcap, sizeof (uint64_t))) == 0)
                zone->zone_phys_mcap = mcap;

        return (err);
}

static int
zone_set_sched_class(zone_t *zone, const char *new_class)
{
        char sched_class[PC_CLNMSZ];
        id_t classid;
        int err;

        ASSERT(zone != global_zone);
        if ((err = copyinstr(new_class, sched_class, PC_CLNMSZ, NULL)) != 0)
                return (err);   /* EFAULT or ENAMETOOLONG */

        if (getcid(sched_class, &classid) != 0 || CLASS_KERNEL(classid))
                return (set_errno(EINVAL));
        zone->zone_defaultcid = classid;
        ASSERT(zone->zone_defaultcid > 0 &&
            zone->zone_defaultcid < loaded_classes);

        return (0);
}

/*
 * Block indefinitely waiting for (zone_status >= status)
 */
void
zone_status_wait(zone_t *zone, zone_status_t status)
{
        ASSERT(status > ZONE_MIN_STATE && status <= ZONE_MAX_STATE);

        mutex_enter(&zone_status_lock);
        while (zone->zone_status < status) {
                cv_wait(&zone->zone_cv, &zone_status_lock);
        }
        mutex_exit(&zone_status_lock);
}

/*
 * Private CPR-safe version of zone_status_wait().
 */
static void
zone_status_wait_cpr(zone_t *zone, zone_status_t status, char *str)
{
        callb_cpr_t cprinfo;

        ASSERT(status > ZONE_MIN_STATE && status <= ZONE_MAX_STATE);

        CALLB_CPR_INIT(&cprinfo, &zone_status_lock, callb_generic_cpr,
            str);
        mutex_enter(&zone_status_lock);
        while (zone->zone_status < status) {
                CALLB_CPR_SAFE_BEGIN(&cprinfo);
                cv_wait(&zone->zone_cv, &zone_status_lock);
                CALLB_CPR_SAFE_END(&cprinfo, &zone_status_lock);
        }
        /*
         * zone_status_lock is implicitly released by the following.
         */
        CALLB_CPR_EXIT(&cprinfo);
}

/*
 * Block until zone enters requested state or signal is received.  Return (0)
 * if signaled, non-zero otherwise.
 */
int
zone_status_wait_sig(zone_t *zone, zone_status_t status)
{
        ASSERT(status > ZONE_MIN_STATE && status <= ZONE_MAX_STATE);

        mutex_enter(&zone_status_lock);
        while (zone->zone_status < status) {
                if (!cv_wait_sig(&zone->zone_cv, &zone_status_lock)) {
                        mutex_exit(&zone_status_lock);
                        return (0);
                }
        }
        mutex_exit(&zone_status_lock);
        return (1);
}

/*
 * Block until the zone enters the requested state or the timeout expires,
 * whichever happens first.  Return (-1) if operation timed out, time remaining
 * otherwise.
 */
clock_t
zone_status_timedwait(zone_t *zone, clock_t tim, zone_status_t status)
{
        clock_t timeleft = 0;

        ASSERT(status > ZONE_MIN_STATE && status <= ZONE_MAX_STATE);

        mutex_enter(&zone_status_lock);
        while (zone->zone_status < status && timeleft != -1) {
                timeleft = cv_timedwait(&zone->zone_cv, &zone_status_lock, tim);
        }
        mutex_exit(&zone_status_lock);
        return (timeleft);
}

/*
 * Block until the zone enters the requested state, the current process is
 * signaled,  or the timeout expires, whichever happens first.  Return (-1) if
 * operation timed out, 0 if signaled, time remaining otherwise.
 */
clock_t
zone_status_timedwait_sig(zone_t *zone, clock_t tim, zone_status_t status)
{
        clock_t timeleft = tim - ddi_get_lbolt();

        ASSERT(status > ZONE_MIN_STATE && status <= ZONE_MAX_STATE);

        mutex_enter(&zone_status_lock);
        while (zone->zone_status < status) {
                timeleft = cv_timedwait_sig(&zone->zone_cv, &zone_status_lock,
                    tim);
                if (timeleft <= 0)
                        break;
        }
        mutex_exit(&zone_status_lock);
        return (timeleft);
}

/*
 * Zones have two reference counts: one for references from credential
 * structures (zone_cred_ref), and one (zone_ref) for everything else.
 * This is so we can allow a zone to be rebooted while there are still
 * outstanding cred references, since certain drivers cache dblks (which
 * implicitly results in cached creds).  We wait for zone_ref to drop to
 * 0 (actually 1), but not zone_cred_ref.  The zone structure itself is
 * later freed when the zone_cred_ref drops to 0, though nothing other
 * than the zone id and privilege set should be accessed once the zone
 * is "dead".
 *
 * A debugging flag, zone_wait_for_cred, can be set to a non-zero value
 * to force halt/reboot to block waiting for the zone_cred_ref to drop
 * to 0.  This can be useful to flush out other sources of cached creds
 * that may be less innocuous than the driver case.
 *
 * Zones also provide a tracked reference counting mechanism in which zone
 * references are represented by "crumbs" (zone_ref structures).  Crumbs help
 * debuggers determine the sources of leaked zone references.  See
 * zone_hold_ref() and zone_rele_ref() below for more information.
 */

int zone_wait_for_cred = 0;

static void
zone_hold_locked(zone_t *z)
{
        ASSERT(MUTEX_HELD(&z->zone_lock));
        z->zone_ref++;
        ASSERT(z->zone_ref != 0);
}

/*
 * Increment the specified zone's reference count.  The zone's zone_t structure
 * will not be freed as long as the zone's reference count is nonzero.
 * Decrement the zone's reference count via zone_rele().
 *
 * NOTE: This function should only be used to hold zones for short periods of
 * time.  Use zone_hold_ref() if the zone must be held for a long time.
 */
void
zone_hold(zone_t *z)
{
        mutex_enter(&z->zone_lock);
        zone_hold_locked(z);
        mutex_exit(&z->zone_lock);
}

/*
 * If the non-cred ref count drops to 1 and either the cred ref count
 * is 0 or we aren't waiting for cred references, the zone is ready to
 * be destroyed.
 */
#define ZONE_IS_UNREF(zone)     ((zone)->zone_ref == 1 && \
            (!zone_wait_for_cred || (zone)->zone_cred_ref == 0))

/*
 * Common zone reference release function invoked by zone_rele() and
 * zone_rele_ref().  If subsys is ZONE_REF_NUM_SUBSYS, then the specified
 * zone's subsystem-specific reference counters are not affected by the
 * release.  If ref is not NULL, then the zone_ref_t to which it refers is
 * removed from the specified zone's reference list.  ref must be non-NULL iff
 * subsys is not ZONE_REF_NUM_SUBSYS.
 */
static void
zone_rele_common(zone_t *z, zone_ref_t *ref, zone_ref_subsys_t subsys)
{
        boolean_t wakeup;

        mutex_enter(&z->zone_lock);
        ASSERT(z->zone_ref != 0);
        z->zone_ref--;
        if (subsys != ZONE_REF_NUM_SUBSYS) {
                ASSERT(z->zone_subsys_ref[subsys] != 0);
                z->zone_subsys_ref[subsys]--;
                list_remove(&z->zone_ref_list, ref);
        }
        if (z->zone_ref == 0 && z->zone_cred_ref == 0) {
                /* no more refs, free the structure */
                mutex_exit(&z->zone_lock);
                zone_free(z);
                return;
        }
        /* signal zone_destroy so the zone can finish halting */
        wakeup = (ZONE_IS_UNREF(z) && zone_status_get(z) >= ZONE_IS_DEAD);
        mutex_exit(&z->zone_lock);

        if (wakeup) {
                /*
                 * Grabbing zonehash_lock here effectively synchronizes with
                 * zone_destroy() to avoid missed signals.
                 */
                mutex_enter(&zonehash_lock);
                cv_broadcast(&zone_destroy_cv);
                mutex_exit(&zonehash_lock);
        }
}

/*
 * Decrement the specified zone's reference count.  The specified zone will
 * cease to exist after this function returns if the reference count drops to
 * zero.  This function should be paired with zone_hold().
 */
void
zone_rele(zone_t *z)
{
        zone_rele_common(z, NULL, ZONE_REF_NUM_SUBSYS);
}

/*
 * Initialize a zone reference structure.  This function must be invoked for
 * a reference structure before the structure is passed to zone_hold_ref().
 */
void
zone_init_ref(zone_ref_t *ref)
{
        ref->zref_zone = NULL;
        list_link_init(&ref->zref_linkage);
}

/*
 * Acquire a reference to zone z.  The caller must specify the
 * zone_ref_subsys_t constant associated with its subsystem.  The specified
 * zone_ref_t structure will represent a reference to the specified zone.  Use
 * zone_rele_ref() to release the reference.
 *
 * The referenced zone_t structure will not be freed as long as the zone_t's
 * zone_status field is not ZONE_IS_DEAD and the zone has outstanding
 * references.
 *
 * NOTE: The zone_ref_t structure must be initialized before it is used.
 * See zone_init_ref() above.
 */
void
zone_hold_ref(zone_t *z, zone_ref_t *ref, zone_ref_subsys_t subsys)
{
        ASSERT(subsys >= 0 && subsys < ZONE_REF_NUM_SUBSYS);

        /*
         * Prevent consumers from reusing a reference structure before
         * releasing it.
         */
        VERIFY(ref->zref_zone == NULL);

        ref->zref_zone = z;
        mutex_enter(&z->zone_lock);
        zone_hold_locked(z);
        z->zone_subsys_ref[subsys]++;
        ASSERT(z->zone_subsys_ref[subsys] != 0);
        list_insert_head(&z->zone_ref_list, ref);
        mutex_exit(&z->zone_lock);
}

/*
 * Release the zone reference represented by the specified zone_ref_t.
 * The reference is invalid after it's released; however, the zone_ref_t
 * structure can be reused without having to invoke zone_init_ref().
 * subsys should be the same value that was passed to zone_hold_ref()
 * when the reference was acquired.
 */
void
zone_rele_ref(zone_ref_t *ref, zone_ref_subsys_t subsys)
{
        zone_rele_common(ref->zref_zone, ref, subsys);

        /*
         * Set the zone_ref_t's zref_zone field to NULL to generate panics
         * when consumers dereference the reference.  This helps us catch
         * consumers who use released references.  Furthermore, this lets
         * consumers reuse the zone_ref_t structure without having to
         * invoke zone_init_ref().
         */
        ref->zref_zone = NULL;
}

void
zone_cred_hold(zone_t *z)
{
        mutex_enter(&z->zone_lock);
        z->zone_cred_ref++;
        ASSERT(z->zone_cred_ref != 0);
        mutex_exit(&z->zone_lock);
}

void
zone_cred_rele(zone_t *z)
{
        boolean_t wakeup;

        mutex_enter(&z->zone_lock);
        ASSERT(z->zone_cred_ref != 0);
        z->zone_cred_ref--;
        if (z->zone_ref == 0 && z->zone_cred_ref == 0) {
                /* no more refs, free the structure */
                mutex_exit(&z->zone_lock);
                zone_free(z);
                return;
        }
        /*
         * If zone_destroy is waiting for the cred references to drain
         * out, and they have, signal it.
         */
        wakeup = (zone_wait_for_cred && ZONE_IS_UNREF(z) &&
            zone_status_get(z) >= ZONE_IS_DEAD);
        mutex_exit(&z->zone_lock);

        if (wakeup) {
                /*
                 * Grabbing zonehash_lock here effectively synchronizes with
                 * zone_destroy() to avoid missed signals.
                 */
                mutex_enter(&zonehash_lock);
                cv_broadcast(&zone_destroy_cv);
                mutex_exit(&zonehash_lock);
        }
}

void
zone_task_hold(zone_t *z)
{
        mutex_enter(&z->zone_lock);
        z->zone_ntasks++;
        ASSERT(z->zone_ntasks != 0);
        mutex_exit(&z->zone_lock);
}

void
zone_task_rele(zone_t *zone)
{
        uint_t refcnt;

        mutex_enter(&zone->zone_lock);
        ASSERT(zone->zone_ntasks != 0);
        refcnt = --zone->zone_ntasks;
        if (refcnt > 1) {       /* Common case */
                mutex_exit(&zone->zone_lock);
                return;
        }
        zone_hold_locked(zone); /* so we can use the zone_t later */
        mutex_exit(&zone->zone_lock);
        if (refcnt == 1) {
                /*
                 * See if the zone is shutting down.
                 */
                mutex_enter(&zone_status_lock);
                if (zone_status_get(zone) != ZONE_IS_SHUTTING_DOWN) {
                        goto out;
                }

                /*
                 * Make sure the ntasks didn't change since we
                 * dropped zone_lock.
                 */
                mutex_enter(&zone->zone_lock);
                if (refcnt != zone->zone_ntasks) {
                        mutex_exit(&zone->zone_lock);
                        goto out;
                }
                mutex_exit(&zone->zone_lock);

                /*
                 * No more user processes in the zone.  The zone is empty.
                 */
                zone_status_set(zone, ZONE_IS_EMPTY);
                goto out;
        }

        ASSERT(refcnt == 0);
        /*
         * zsched has exited; the zone is dead.
         */
        zone->zone_zsched = NULL;               /* paranoia */
        mutex_enter(&zone_status_lock);
        zone_status_set(zone, ZONE_IS_DEAD);
out:
        mutex_exit(&zone_status_lock);
        zone_rele(zone);
}

zoneid_t
getzoneid(void)
{
        return (curproc->p_zone->zone_id);
}

/*
 * Internal versions of zone_find_by_*().  These don't zone_hold() or
 * check the validity of a zone's state.
 */
static zone_t *
zone_find_all_by_id(zoneid_t zoneid)
{
        mod_hash_val_t hv;
        zone_t *zone = NULL;

        ASSERT(MUTEX_HELD(&zonehash_lock));

        if (mod_hash_find(zonehashbyid,
            (mod_hash_key_t)(uintptr_t)zoneid, &hv) == 0)
                zone = (zone_t *)hv;
        return (zone);
}

static zone_t *
zone_find_all_by_name(char *name)
{
        mod_hash_val_t hv;
        zone_t *zone = NULL;

        ASSERT(MUTEX_HELD(&zonehash_lock));

        if (mod_hash_find(zonehashbyname, (mod_hash_key_t)name, &hv) == 0)
                zone = (zone_t *)hv;
        return (zone);
}

/*
 * Public interface for looking up a zone by zoneid.  Only returns the zone if
 * it is fully initialized, and has not yet begun the zone_destroy() sequence.
 * Caller must call zone_rele() once it is done with the zone.
 *
 * The zone may begin the zone_destroy() sequence immediately after this
 * function returns, but may be safely used until zone_rele() is called.
 */
zone_t *
zone_find_by_id(zoneid_t zoneid)
{
        zone_t *zone;
        zone_status_t status;

        mutex_enter(&zonehash_lock);
        if ((zone = zone_find_all_by_id(zoneid)) == NULL) {
                mutex_exit(&zonehash_lock);
                return (NULL);
        }
        status = zone_status_get(zone);
        if (status < ZONE_IS_READY || status > ZONE_IS_DOWN) {
                /*
                 * For all practical purposes the zone doesn't exist.
                 */
                mutex_exit(&zonehash_lock);
                return (NULL);
        }
        zone_hold(zone);
        mutex_exit(&zonehash_lock);
        return (zone);
}

/*
 * Similar to zone_find_by_id, but using zone name as the key.
 */
zone_t *
zone_find_by_name(char *name)
{
        zone_t *zone;
        zone_status_t status;

        mutex_enter(&zonehash_lock);
        if ((zone = zone_find_all_by_name(name)) == NULL) {
                mutex_exit(&zonehash_lock);
                return (NULL);
        }
        status = zone_status_get(zone);
        if (status < ZONE_IS_READY || status > ZONE_IS_DOWN) {
                /*
                 * For all practical purposes the zone doesn't exist.
                 */
                mutex_exit(&zonehash_lock);
                return (NULL);
        }
        zone_hold(zone);
        mutex_exit(&zonehash_lock);
        return (zone);
}

/*
 * Similar to zone_find_by_id(), using the path as a key.  For instance,
 * if there is a zone "foo" rooted at /foo/root, and the path argument
 * is "/foo/root/proc", it will return the held zone_t corresponding to
 * zone "foo".
 *
 * zone_find_by_path() always returns a non-NULL value, since at the
 * very least every path will be contained in the global zone.
 *
 * As with the other zone_find_by_*() functions, the caller is
 * responsible for zone_rele()ing the return value of this function.
 */
zone_t *
zone_find_by_path(const char *path)
{
        zone_t *zone;
        zone_t *zret = NULL;
        zone_status_t status;

        if (path == NULL) {
                /*
                 * Call from rootconf().
                 */
                zone_hold(global_zone);
                return (global_zone);
        }
        ASSERT(*path == '/');
        mutex_enter(&zonehash_lock);
        for (zone = list_head(&zone_active); zone != NULL;
            zone = list_next(&zone_active, zone)) {
                if (ZONE_PATH_VISIBLE(path, zone))
                        zret = zone;
        }
        ASSERT(zret != NULL);
        status = zone_status_get(zret);
        if (status < ZONE_IS_READY || status > ZONE_IS_DOWN) {
                /*
                 * Zone practically doesn't exist.
                 */
                zret = global_zone;
        }
        zone_hold(zret);
        mutex_exit(&zonehash_lock);
        return (zret);
}

/*
 * Public interface for updating per-zone load averages.  Called once per
 * second.
 *
 * Based on loadavg_update(), genloadavg() and calcloadavg() from clock.c.
 */
void
zone_loadavg_update()
{
        zone_t *zp;
        zone_status_t status;
        struct loadavg_s *lavg;
        hrtime_t zone_total;
        int i;
        hrtime_t hr_avg;
        int nrun;
        static int64_t f[3] = { 135, 27, 9 };
        int64_t q, r;

        mutex_enter(&zonehash_lock);
        for (zp = list_head(&zone_active); zp != NULL;
            zp = list_next(&zone_active, zp)) {
                mutex_enter(&zp->zone_lock);

                /* Skip zones that are on the way down or not yet up */
                status = zone_status_get(zp);
                if (status < ZONE_IS_READY || status >= ZONE_IS_DOWN) {
                        /* For all practical purposes the zone doesn't exist. */
                        mutex_exit(&zp->zone_lock);
                        continue;
                }

                /*
                 * Update the 10 second moving average data in zone_loadavg.
                 */
                lavg = &zp->zone_loadavg;

                zone_total = zp->zone_utime + zp->zone_stime + zp->zone_wtime;
                scalehrtime(&zone_total);

                /* The zone_total should always be increasing. */
                lavg->lg_loads[lavg->lg_cur] = (zone_total > lavg->lg_total) ?
                    zone_total - lavg->lg_total : 0;
                lavg->lg_cur = (lavg->lg_cur + 1) % S_LOADAVG_SZ;
                /* lg_total holds the prev. 1 sec. total */
                lavg->lg_total = zone_total;

                /*
                 * To simplify the calculation, we don't calculate the load avg.
                 * until the zone has been up for at least 10 seconds and our
                 * moving average is thus full.
                 */
                if ((lavg->lg_len + 1) < S_LOADAVG_SZ) {
                        lavg->lg_len++;
                        mutex_exit(&zp->zone_lock);
                        continue;
                }

                /* Now calculate the 1min, 5min, 15 min load avg. */
                hr_avg = 0;
                for (i = 0; i < S_LOADAVG_SZ; i++)
                        hr_avg += lavg->lg_loads[i];
                hr_avg = hr_avg / S_LOADAVG_SZ;
                nrun = hr_avg / (NANOSEC / LGRP_LOADAVG_IN_THREAD_MAX);

                /* Compute load avg. See comment in calcloadavg() */
                for (i = 0; i < 3; i++) {
                        q = (zp->zone_hp_avenrun[i] >> 16) << 7;
                        r = (zp->zone_hp_avenrun[i] & 0xffff) << 7;
                        zp->zone_hp_avenrun[i] +=
                            ((nrun - q) * f[i] - ((r * f[i]) >> 16)) >> 4;

                        /* avenrun[] can only hold 31 bits of load avg. */
                        if (zp->zone_hp_avenrun[i] <
                            ((uint64_t)1<<(31+16-FSHIFT)))
                                zp->zone_avenrun[i] = (int32_t)
                                    (zp->zone_hp_avenrun[i] >> (16 - FSHIFT));
                        else
                                zp->zone_avenrun[i] = 0x7fffffff;
                }

                mutex_exit(&zp->zone_lock);
        }
        mutex_exit(&zonehash_lock);
}

/*
 * Get the number of cpus visible to this zone.  The system-wide global
 * 'ncpus' is returned if pools are disabled, the caller is in the
 * global zone, or a NULL zone argument is passed in.
 */
int
zone_ncpus_get(zone_t *zone)
{
        int myncpus = zone == NULL ? 0 : zone->zone_ncpus;

        return (myncpus != 0 ? myncpus : ncpus);
}

/*
 * Get the number of online cpus visible to this zone.  The system-wide
 * global 'ncpus_online' is returned if pools are disabled, the caller
 * is in the global zone, or a NULL zone argument is passed in.
 */
int
zone_ncpus_online_get(zone_t *zone)
{
        int myncpus_online = zone == NULL ? 0 : zone->zone_ncpus_online;

        return (myncpus_online != 0 ? myncpus_online : ncpus_online);
}

/*
 * Return the pool to which the zone is currently bound.
 */
pool_t *
zone_pool_get(zone_t *zone)
{
        ASSERT(pool_lock_held());

        return (zone->zone_pool);
}

/*
 * Set the zone's pool pointer and update the zone's visibility to match
 * the resources in the new pool.
 */
void
zone_pool_set(zone_t *zone, pool_t *pool)
{
        ASSERT(pool_lock_held());
        ASSERT(MUTEX_HELD(&cpu_lock));

        zone->zone_pool = pool;
        zone_pset_set(zone, pool->pool_pset->pset_id);
}

/*
 * Return the cached value of the id of the processor set to which the
 * zone is currently bound.  The value will be ZONE_PS_INVAL if the pools
 * facility is disabled.
 */
psetid_t
zone_pset_get(zone_t *zone)
{
        ASSERT(MUTEX_HELD(&cpu_lock));

        return (zone->zone_psetid);
}

/*
 * Set the cached value of the id of the processor set to which the zone
 * is currently bound.  Also update the zone's visibility to match the
 * resources in the new processor set.
 */
void
zone_pset_set(zone_t *zone, psetid_t newpsetid)
{
        psetid_t oldpsetid;

        ASSERT(MUTEX_HELD(&cpu_lock));
        oldpsetid = zone_pset_get(zone);

        if (oldpsetid == newpsetid)
                return;
        /*
         * Global zone sees all.
         */
        if (zone != global_zone) {
                zone->zone_psetid = newpsetid;
                if (newpsetid != ZONE_PS_INVAL)
                        pool_pset_visibility_add(newpsetid, zone);
                if (oldpsetid != ZONE_PS_INVAL)
                        pool_pset_visibility_remove(oldpsetid, zone);
        }
        /*
         * Disabling pools, so we should start using the global values
         * for ncpus and ncpus_online.
         */
        if (newpsetid == ZONE_PS_INVAL) {
                zone->zone_ncpus = 0;
                zone->zone_ncpus_online = 0;
        }
}

/*
 * Walk the list of active zones and issue the provided callback for
 * each of them.
 *
 * Caller must not be holding any locks that may be acquired under
 * zonehash_lock.  See comment at the beginning of the file for a list of
 * common locks and their interactions with zones.
 */
int
zone_walk(int (*cb)(zone_t *, void *), void *data)
{
        zone_t *zone;
        int ret = 0;
        zone_status_t status;

        mutex_enter(&zonehash_lock);
        for (zone = list_head(&zone_active); zone != NULL;
            zone = list_next(&zone_active, zone)) {
                /*
                 * Skip zones that shouldn't be externally visible.
                 */
                status = zone_status_get(zone);
                if (status < ZONE_IS_READY || status > ZONE_IS_DOWN)
                        continue;
                /*
                 * Bail immediately if any callback invocation returns a
                 * non-zero value.
                 */
                ret = (*cb)(zone, data);
                if (ret != 0)
                        break;
        }
        mutex_exit(&zonehash_lock);
        return (ret);
}

static int
zone_set_root(zone_t *zone, const char *upath)
{
        vnode_t *vp;
        int trycount;
        int error = 0;
        char *path;
        struct pathname upn, pn;
        size_t pathlen;

        if ((error = pn_get((char *)upath, UIO_USERSPACE, &upn)) != 0)
                return (error);

        pn_alloc(&pn);

        /* prevent infinite loop */
        trycount = 10;
        for (;;) {
                if (--trycount <= 0) {
                        error = ESTALE;
                        goto out;
                }

                if ((error = lookuppn(&upn, &pn, FOLLOW, NULLVPP, &vp)) == 0) {
                        /*
                         * fop_access() may cover 'vp' with a new
                         * filesystem, if 'vp' is an autoFS vnode.
                         * Get the new 'vp' if so.
                         */
                        if ((error =
                            fop_access(vp, VEXEC, 0, CRED(), NULL)) == 0 &&
                            (!vn_ismntpt(vp) ||
                            (error = traverse(&vp)) == 0)) {
                                pathlen = pn.pn_pathlen + 2;
                                path = kmem_alloc(pathlen, KM_SLEEP);
                                (void) strncpy(path, pn.pn_path,
                                    pn.pn_pathlen + 1);
                                path[pathlen - 2] = '/';
                                path[pathlen - 1] = '\0';
                                pn_free(&pn);
                                pn_free(&upn);

                                /* Success! */
                                break;
                        }
                        VN_RELE(vp);
                }
                if (error != ESTALE)
                        goto out;
        }

        ASSERT(error == 0);
        zone->zone_rootvp = vp;         /* we hold a reference to vp */
        zone->zone_rootpath = path;
        zone->zone_rootpathlen = pathlen;
        if (pathlen > 5 && strcmp(path + pathlen - 5, "/lu/") == 0)
                zone->zone_flags |= ZF_IS_SCRATCH;
        return (0);

out:
        pn_free(&pn);
        pn_free(&upn);
        return (error);
}

#define isalnum(c)      (((c) >= '0' && (c) <= '9') || \
                        ((c) >= 'a' && (c) <= 'z') || \
                        ((c) >= 'A' && (c) <= 'Z'))

static int
zone_set_name(zone_t *zone, const char *uname)
{
        char *kname = kmem_zalloc(ZONENAME_MAX, KM_SLEEP);
        size_t len;
        int i, err;

        if ((err = copyinstr(uname, kname, ZONENAME_MAX, &len)) != 0) {
                kmem_free(kname, ZONENAME_MAX);
                return (err);   /* EFAULT or ENAMETOOLONG */
        }

        /* must be less than ZONENAME_MAX */
        if (len == ZONENAME_MAX && kname[ZONENAME_MAX - 1] != '\0') {
                kmem_free(kname, ZONENAME_MAX);
                return (EINVAL);
        }

        /*
         * Name must start with an alphanumeric and must contain only
         * alphanumerics, '-', '_' and '.'.
         */
        if (!isalnum(kname[0])) {
                kmem_free(kname, ZONENAME_MAX);
                return (EINVAL);
        }
        for (i = 1; i < len - 1; i++) {
                if (!isalnum(kname[i]) && kname[i] != '-' && kname[i] != '_' &&
                    kname[i] != '.') {
                        kmem_free(kname, ZONENAME_MAX);
                        return (EINVAL);
                }
        }

        zone->zone_name = kname;
        return (0);
}

/*
 * Gets the 32-bit hostid of the specified zone as an unsigned int.  If 'zonep'
 * is NULL or it points to a zone with no hostid emulation, then the machine's
 * hostid (i.e., the global zone's hostid) is returned.  This function returns
 * zero if neither the zone nor the host machine (global zone) have hostids.  It
 * returns HW_INVALID_HOSTID if the function attempts to return the machine's
 * hostid and the machine's hostid is invalid.
 */
uint32_t
zone_get_hostid(zone_t *zonep)
{
        unsigned long machine_hostid;

        if (zonep == NULL || zonep->zone_hostid == HW_INVALID_HOSTID) {
                if (ddi_strtoul(hw_serial, NULL, 10, &machine_hostid) != 0)
                        return (HW_INVALID_HOSTID);
                return ((uint32_t)machine_hostid);
        }
        return (zonep->zone_hostid);
}

/*
 * Similar to thread_create(), but makes sure the thread is in the appropriate
 * zone's zsched process (curproc->p_zone->zone_zsched) before returning.
 */
/*ARGSUSED*/
kthread_t *
zthread_create(
    caddr_t stk,
    size_t stksize,
    void (*proc)(),
    void *arg,
    size_t len,
    pri_t pri)
{
        kthread_t *t;
        zone_t *zone = curproc->p_zone;
        proc_t *pp = zone->zone_zsched;

        zone_hold(zone);        /* Reference to be dropped when thread exits */

        /*
         * No-one should be trying to create threads if the zone is shutting
         * down and there aren't any kernel threads around.  See comment
         * in zthread_exit().
         */
        ASSERT(!(zone->zone_kthreads == NULL &&
            zone_status_get(zone) >= ZONE_IS_EMPTY));
        /*
         * Create a thread, but don't let it run until we've finished setting
         * things up.
         */
        t = thread_create(stk, stksize, proc, arg, len, pp, TS_STOPPED, pri);
        ASSERT(t->t_forw == NULL);
        mutex_enter(&zone_status_lock);
        if (zone->zone_kthreads == NULL) {
                t->t_forw = t->t_back = t;
        } else {
                kthread_t *tx = zone->zone_kthreads;

                t->t_forw = tx;
                t->t_back = tx->t_back;
                tx->t_back->t_forw = t;
                tx->t_back = t;
        }
        zone->zone_kthreads = t;
        mutex_exit(&zone_status_lock);

        mutex_enter(&pp->p_lock);
        t->t_proc_flag |= TP_ZTHREAD;
        project_rele(t->t_proj);
        t->t_proj = project_hold(pp->p_task->tk_proj);

        /*
         * Setup complete, let it run.
         */
        thread_lock(t);
        t->t_schedflag |= TS_ALLSTART;
        setrun_locked(t);
        thread_unlock(t);

        mutex_exit(&pp->p_lock);

        return (t);
}

/*
 * Similar to thread_exit().  Must be called by threads created via
 * zthread_exit().
 */
void
zthread_exit(void)
{
        kthread_t *t = curthread;
        proc_t *pp = curproc;
        zone_t *zone = pp->p_zone;

        mutex_enter(&zone_status_lock);

        /*
         * Reparent to p0
         */
        kpreempt_disable();
        mutex_enter(&pp->p_lock);
        t->t_proc_flag &= ~TP_ZTHREAD;
        t->t_procp = &p0;
        hat_thread_exit(t);
        mutex_exit(&pp->p_lock);
        kpreempt_enable();

        if (t->t_back == t) {
                ASSERT(t->t_forw == t);
                /*
                 * If the zone is empty, once the thread count
                 * goes to zero no further kernel threads can be
                 * created.  This is because if the creator is a process
                 * in the zone, then it must have exited before the zone
                 * state could be set to ZONE_IS_EMPTY.
                 * Otherwise, if the creator is a kernel thread in the
                 * zone, the thread count is non-zero.
                 *
                 * This really means that non-zone kernel threads should
                 * not create zone kernel threads.
                 */
                zone->zone_kthreads = NULL;
                if (zone_status_get(zone) == ZONE_IS_EMPTY) {
                        zone_status_set(zone, ZONE_IS_DOWN);
                        /*
                         * Remove any CPU caps on this zone.
                         */
                        cpucaps_zone_remove(zone);
                }
        } else {
                t->t_forw->t_back = t->t_back;
                t->t_back->t_forw = t->t_forw;
                if (zone->zone_kthreads == t)
                        zone->zone_kthreads = t->t_forw;
        }
        mutex_exit(&zone_status_lock);
        zone_rele(zone);
        thread_exit();
        /* NOTREACHED */
}

static void
zone_chdir(vnode_t *vp, vnode_t **vpp, proc_t *pp)
{
        vnode_t *oldvp;

        /* we're going to hold a reference here to the directory */
        VN_HOLD(vp);

        /* update abs cwd/root path see c2/audit.c */
        if (AU_AUDITING())
                audit_chdirec(vp, vpp);

        mutex_enter(&pp->p_lock);
        oldvp = *vpp;
        *vpp = vp;
        mutex_exit(&pp->p_lock);
        if (oldvp != NULL)
                VN_RELE(oldvp);
}

/*
 * Convert an rctl value represented by an nvlist_t into an rctl_val_t.
 */
static int
nvlist2rctlval(nvlist_t *nvl, rctl_val_t *rv)
{
        nvpair_t *nvp = NULL;
        boolean_t priv_set = B_FALSE;
        boolean_t limit_set = B_FALSE;
        boolean_t action_set = B_FALSE;

        while ((nvp = nvlist_next_nvpair(nvl, nvp)) != NULL) {
                const char *name;
                uint64_t ui64;

                name = nvpair_name(nvp);
                if (nvpair_type(nvp) != DATA_TYPE_UINT64)
                        return (EINVAL);
                (void) nvpair_value_uint64(nvp, &ui64);
                if (strcmp(name, "privilege") == 0) {
                        /*
                         * Currently only privileged values are allowed, but
                         * this may change in the future.
                         */
                        if (ui64 != RCPRIV_PRIVILEGED)
                                return (EINVAL);
                        rv->rcv_privilege = ui64;
                        priv_set = B_TRUE;
                } else if (strcmp(name, "limit") == 0) {
                        rv->rcv_value = ui64;
                        limit_set = B_TRUE;
                } else if (strcmp(name, "action") == 0) {
                        if (ui64 != RCTL_LOCAL_NOACTION &&
                            ui64 != RCTL_LOCAL_DENY)
                                return (EINVAL);
                        rv->rcv_flagaction = ui64;
                        action_set = B_TRUE;
                } else {
                        return (EINVAL);
                }
        }

        if (!(priv_set && limit_set && action_set))
                return (EINVAL);
        rv->rcv_action_signal = 0;
        rv->rcv_action_recipient = NULL;
        rv->rcv_action_recip_pid = -1;
        rv->rcv_firing_time = 0;

        return (0);
}

/*
 * Non-global zone version of start_init.
 */
void
zone_start_init(void)
{
        proc_t *p = ttoproc(curthread);
        zone_t *z = p->p_zone;

        ASSERT(!INGLOBALZONE(curproc));

        /*
         * For all purposes (ZONE_ATTR_INITPID and restart_init),
         * storing just the pid of init is sufficient.
         */
        z->zone_proc_initpid = p->p_pid;

        /*
         * We maintain zone_boot_err so that we can return the cause of the
         * failure back to the caller of the zone_boot syscall.
         */
        p->p_zone->zone_boot_err = start_init_common();

        /*
         * We will prevent booting zones from becoming running zones if the
         * global zone is shutting down.
         */
        mutex_enter(&zone_status_lock);
        if (z->zone_boot_err != 0 || zone_status_get(global_zone) >=
            ZONE_IS_SHUTTING_DOWN) {
                /*
                 * Make sure we are still in the booting state-- we could have
                 * raced and already be shutting down, or even further along.
                 */
                if (zone_status_get(z) == ZONE_IS_BOOTING) {
                        zone_status_set(z, ZONE_IS_SHUTTING_DOWN);
                }
                mutex_exit(&zone_status_lock);
                /* It's gone bad, dispose of the process */
                if (proc_exit(CLD_EXITED, z->zone_boot_err) != 0) {
                        mutex_enter(&p->p_lock);
                        ASSERT(p->p_flag & SEXITLWPS);
                        lwp_exit();
                }
        } else {
                if (zone_status_get(z) == ZONE_IS_BOOTING)
                        zone_status_set(z, ZONE_IS_RUNNING);
                mutex_exit(&zone_status_lock);
                /* cause the process to return to userland. */
                lwp_rtt();
        }
}

struct zsched_arg {
        zone_t *zone;
        nvlist_t *nvlist;
};

/*
 * Per-zone "sched" workalike.  The similarity to "sched" doesn't have
 * anything to do with scheduling, but rather with the fact that
 * per-zone kernel threads are parented to zsched, just like regular
 * kernel threads are parented to sched (p0).
 *
 * zsched is also responsible for launching init for the zone.
 */
static void
zsched(void *arg)
{
        struct zsched_arg *za = arg;
        proc_t *pp = curproc;
        proc_t *initp = proc_init;
        zone_t *zone = za->zone;
        cred_t *cr, *oldcred;
        rctl_set_t *set;
        rctl_alloc_gp_t *gp;
        contract_t *ct = NULL;
        task_t *tk, *oldtk;
        rctl_entity_p_t e;
        kproject_t *pj;

        nvlist_t *nvl = za->nvlist;
        nvpair_t *nvp = NULL;

        bcopy("zsched", PTOU(pp)->u_psargs, sizeof ("zsched"));
        bcopy("zsched", PTOU(pp)->u_comm, sizeof ("zsched"));
        PTOU(pp)->u_argc = 0;
        PTOU(pp)->u_argv = (uintptr_t)NULL;
        PTOU(pp)->u_envp = (uintptr_t)NULL;
        PTOU(pp)->u_commpagep = (uintptr_t)NULL;
        closeall(P_FINFO(pp));

        /*
         * We are this zone's "zsched" process.  As the zone isn't generally
         * visible yet we don't need to grab any locks before initializing its
         * zone_proc pointer.
         */
        zone_hold(zone);  /* this hold is released by zone_destroy() */
        zone->zone_zsched = pp;
        mutex_enter(&pp->p_lock);
        pp->p_zone = zone;
        mutex_exit(&pp->p_lock);

        /*
         * Disassociate process from its 'parent'; parent ourselves to init
         * (pid 1) and change other values as needed.
         */
        sess_create();

        mutex_enter(&pidlock);
        proc_detach(pp);
        pp->p_ppid = 1;
        pp->p_flag |= SZONETOP;
        pp->p_ancpid = 1;
        pp->p_parent = initp;
        pp->p_psibling = NULL;
        if (initp->p_child)
                initp->p_child->p_psibling = pp;
        pp->p_sibling = initp->p_child;
        initp->p_child = pp;

        /* Decrement what newproc() incremented. */
        upcount_dec(crgetruid(CRED()), GLOBAL_ZONEID);
        /*
         * Our credentials are about to become kcred-like, so we don't care
         * about the caller's ruid.
         */
        upcount_inc(crgetruid(kcred), zone->zone_id);
        mutex_exit(&pidlock);

        /*
         * getting out of global zone, so decrement lwp and process counts
         */
        pj = pp->p_task->tk_proj;
        mutex_enter(&global_zone->zone_nlwps_lock);
        pj->kpj_nlwps -= pp->p_lwpcnt;
        global_zone->zone_nlwps -= pp->p_lwpcnt;
        pj->kpj_nprocs--;
        global_zone->zone_nprocs--;
        mutex_exit(&global_zone->zone_nlwps_lock);

        /*
         * Decrement locked memory counts on old zone and project.
         */
        mutex_enter(&global_zone->zone_mem_lock);
        global_zone->zone_locked_mem -= pp->p_locked_mem;
        pj->kpj_data.kpd_locked_mem -= pp->p_locked_mem;
        mutex_exit(&global_zone->zone_mem_lock);

        /*
         * Create and join a new task in project '0' of this zone.
         *
         * We don't need to call holdlwps() since we know we're the only lwp in
         * this process.
         *
         * task_join() returns with p_lock held.
         */
        tk = task_create(0, zone);
        mutex_enter(&cpu_lock);
        oldtk = task_join(tk, 0);

        pj = pp->p_task->tk_proj;

        mutex_enter(&zone->zone_mem_lock);
        zone->zone_locked_mem += pp->p_locked_mem;
        pj->kpj_data.kpd_locked_mem += pp->p_locked_mem;
        mutex_exit(&zone->zone_mem_lock);

        /*
         * add lwp and process counts to zsched's zone, and increment
         * project's task and process count due to the task created in
         * the above task_create.
         */
        mutex_enter(&zone->zone_nlwps_lock);
        pj->kpj_nlwps += pp->p_lwpcnt;
        pj->kpj_ntasks += 1;
        zone->zone_nlwps += pp->p_lwpcnt;
        pj->kpj_nprocs++;
        zone->zone_nprocs++;
        mutex_exit(&zone->zone_nlwps_lock);

        mutex_exit(&curproc->p_lock);
        mutex_exit(&cpu_lock);
        task_rele(oldtk);

        /*
         * The process was created by a process in the global zone, hence the
         * credentials are wrong.  We might as well have kcred-ish credentials.
         */
        cr = zone->zone_kcred;
        crhold(cr);
        mutex_enter(&pp->p_crlock);
        oldcred = pp->p_cred;
        pp->p_cred = cr;
        mutex_exit(&pp->p_crlock);
        crfree(oldcred);

        /*
         * Hold credentials again (for thread)
         */
        crhold(cr);

        /*
         * p_lwpcnt can't change since this is a kernel process.
         */
        crset(pp, cr);

        /*
         * Chroot
         */
        zone_chdir(zone->zone_rootvp, &PTOU(pp)->u_cdir, pp);
        zone_chdir(zone->zone_rootvp, &PTOU(pp)->u_rdir, pp);

        /*
         * Initialize zone's rctl set.
         */
        set = rctl_set_create();
        gp = rctl_set_init_prealloc(RCENTITY_ZONE);
        mutex_enter(&pp->p_lock);
        e.rcep_p.zone = zone;
        e.rcep_t = RCENTITY_ZONE;
        zone->zone_rctls = rctl_set_init(RCENTITY_ZONE, pp, &e, set, gp);
        mutex_exit(&pp->p_lock);
        rctl_prealloc_destroy(gp);

        /*
         * Apply the rctls passed in to zone_create().  This is basically a list
         * assignment: all of the old values are removed and the new ones
         * inserted.  That is, if an empty list is passed in, all values are
         * removed.
         */
        while ((nvp = nvlist_next_nvpair(nvl, nvp)) != NULL) {
                rctl_dict_entry_t *rde;
                rctl_hndl_t hndl;
                char *name;
                nvlist_t **nvlarray;
                uint_t i, nelem;
                int error;      /* For ASSERT()s */

                name = nvpair_name(nvp);
                hndl = rctl_hndl_lookup(name);
                ASSERT(hndl != -1);
                rde = rctl_dict_lookup_hndl(hndl);
                ASSERT(rde != NULL);

                for (; /* ever */; ) {
                        rctl_val_t oval;

                        mutex_enter(&pp->p_lock);
                        error = rctl_local_get(hndl, NULL, &oval, pp);
                        mutex_exit(&pp->p_lock);
                        ASSERT(error == 0);     /* Can't fail for RCTL_FIRST */
                        ASSERT(oval.rcv_privilege != RCPRIV_BASIC);
                        if (oval.rcv_privilege == RCPRIV_SYSTEM)
                                break;
                        mutex_enter(&pp->p_lock);
                        error = rctl_local_delete(hndl, &oval, pp);
                        mutex_exit(&pp->p_lock);
                        ASSERT(error == 0);
                }
                error = nvpair_value_nvlist_array(nvp, &nvlarray, &nelem);
                ASSERT(error == 0);
                for (i = 0; i < nelem; i++) {
                        rctl_val_t *nvalp;

                        nvalp = kmem_cache_alloc(rctl_val_cache, KM_SLEEP);
                        error = nvlist2rctlval(nvlarray[i], nvalp);
                        ASSERT(error == 0);
                        /*
                         * rctl_local_insert can fail if the value being
                         * inserted is a duplicate; this is OK.
                         */
                        mutex_enter(&pp->p_lock);
                        if (rctl_local_insert(hndl, nvalp, pp) != 0)
                                kmem_cache_free(rctl_val_cache, nvalp);
                        mutex_exit(&pp->p_lock);
                }
        }

        /*
         * Tell the world that we're done setting up.
         *
         * At this point we want to set the zone status to ZONE_IS_INITIALIZED
         * and atomically set the zone's processor set visibility.  Once
         * we drop pool_lock() this zone will automatically get updated
         * to reflect any future changes to the pools configuration.
         *
         * Note that after we drop the locks below (zonehash_lock in
         * particular) other operations such as a zone_getattr call can
         * now proceed and observe the zone. That is the reason for doing a
         * state transition to the INITIALIZED state.
         */
        pool_lock();
        mutex_enter(&cpu_lock);
        mutex_enter(&zonehash_lock);
        zone_uniqid(zone);
        zone_zsd_configure(zone);
        if (pool_state == POOL_ENABLED)
                zone_pset_set(zone, pool_default->pool_pset->pset_id);
        mutex_enter(&zone_status_lock);
        ASSERT(zone_status_get(zone) == ZONE_IS_UNINITIALIZED);
        zone_status_set(zone, ZONE_IS_INITIALIZED);
        mutex_exit(&zone_status_lock);
        mutex_exit(&zonehash_lock);
        mutex_exit(&cpu_lock);
        pool_unlock();

        /* Now call the create callback for this key */
        zsd_apply_all_keys(zsd_apply_create, zone);

        /* The callbacks are complete. Mark ZONE_IS_READY */
        mutex_enter(&zone_status_lock);
        ASSERT(zone_status_get(zone) == ZONE_IS_INITIALIZED);
        zone_status_set(zone, ZONE_IS_READY);
        mutex_exit(&zone_status_lock);

        /*
         * Once we see the zone transition to the ZONE_IS_BOOTING state,
         * we launch init, and set the state to running.
         */
        zone_status_wait_cpr(zone, ZONE_IS_BOOTING, "zsched");

        if (zone_status_get(zone) == ZONE_IS_BOOTING) {
                id_t cid;

                /*
                 * Ok, this is a little complicated.  We need to grab the
                 * zone's pool's scheduling class ID; note that by now, we
                 * are already bound to a pool if we need to be (zoneadmd
                 * will have done that to us while we're in the READY
                 * state).  *But* the scheduling class for the zone's 'init'
                 * must be explicitly passed to newproc, which doesn't
                 * respect pool bindings.
                 *
                 * We hold the pool_lock across the call to newproc() to
                 * close the obvious race: the pool's scheduling class
                 * could change before we manage to create the LWP with
                 * classid 'cid'.
                 */
                pool_lock();
                if (zone->zone_defaultcid > 0)
                        cid = zone->zone_defaultcid;
                else
                        cid = pool_get_class(zone->zone_pool);
                if (cid == -1)
                        cid = defaultcid;

                /*
                 * If this fails, zone_boot will ultimately fail.  The
                 * state of the zone will be set to SHUTTING_DOWN-- userland
                 * will have to tear down the zone, and fail, or try again.
                 */
                if ((zone->zone_boot_err = newproc(zone_start_init, NULL, cid,
                    minclsyspri - 1, &ct, 0)) != 0) {
                        mutex_enter(&zone_status_lock);
                        zone_status_set(zone, ZONE_IS_SHUTTING_DOWN);
                        mutex_exit(&zone_status_lock);
                } else {
                        zone->zone_boot_time = gethrestime_sec();
                }

                pool_unlock();
        }

        /*
         * Wait for zone_destroy() to be called.  This is what we spend
         * most of our life doing.
         */
        zone_status_wait_cpr(zone, ZONE_IS_DYING, "zsched");

        if (ct)
                /*
                 * At this point the process contract should be empty.
                 * (Though if it isn't, it's not the end of the world.)
                 */
                VERIFY(contract_abandon(ct, curproc, B_TRUE) == 0);

        /*
         * Allow kcred to be freed when all referring processes
         * (including this one) go away.  We can't just do this in
         * zone_free because we need to wait for the zone_cred_ref to
         * drop to 0 before calling zone_free, and the existence of
         * zone_kcred will prevent that.  Thus, we call crfree here to
         * balance the crdup in zone_create.  The crhold calls earlier
         * in zsched will be dropped when the thread and process exit.
         */
        crfree(zone->zone_kcred);
        zone->zone_kcred = NULL;

        exit(CLD_EXITED, 0);
}

/*
 * Helper function to determine if there are any submounts of the
 * provided path.  Used to make sure the zone doesn't "inherit" any
 * mounts from before it is created.
 */
static uint_t
zone_mount_count(const char *rootpath)
{
        vfs_t *vfsp;
        uint_t count = 0;
        size_t rootpathlen = strlen(rootpath);

        /*
         * Holding zonehash_lock prevents race conditions with
         * vfs_list_add()/vfs_list_remove() since we serialize with
         * zone_find_by_path().
         */
        ASSERT(MUTEX_HELD(&zonehash_lock));
        /*
         * The rootpath must end with a '/'
         */
        ASSERT(rootpath[rootpathlen - 1] == '/');

        /*
         * This intentionally does not count the rootpath itself if that
         * happens to be a mount point.
         */
        vfs_list_read_lock();
        vfsp = rootvfs;
        do {
                if (strncmp(rootpath, refstr_value(vfsp->vfs_mntpt),
                    rootpathlen) == 0)
                        count++;
                vfsp = vfsp->vfs_next;
        } while (vfsp != rootvfs);
        vfs_list_unlock();
        return (count);
}

/*
 * Helper function to make sure that a zone created on 'rootpath'
 * wouldn't end up containing other zones' rootpaths.
 */
static boolean_t
zone_is_nested(const char *rootpath)
{
        zone_t *zone;
        size_t rootpathlen = strlen(rootpath);
        size_t len;

        ASSERT(MUTEX_HELD(&zonehash_lock));

        /*
         * zone_set_root() appended '/' and '\0' at the end of rootpath
         */
        if ((rootpathlen <= 3) && (rootpath[0] == '/') &&
            (rootpath[1] == '/') && (rootpath[2] == '\0'))
                return (B_TRUE);

        for (zone = list_head(&zone_active); zone != NULL;
            zone = list_next(&zone_active, zone)) {
                if (zone == global_zone)
                        continue;
                len = strlen(zone->zone_rootpath);
                if (strncmp(rootpath, zone->zone_rootpath,
                    MIN(rootpathlen, len)) == 0)
                        return (B_TRUE);
        }
        return (B_FALSE);
}

static int
zone_set_privset(zone_t *zone, const priv_set_t *zone_privs,
    size_t zone_privssz)
{
        priv_set_t *privs;

        if (zone_privssz < sizeof (priv_set_t))
                return (ENOMEM);

        privs = kmem_alloc(sizeof (priv_set_t), KM_SLEEP);

        if (copyin(zone_privs, privs, sizeof (priv_set_t))) {
                kmem_free(privs, sizeof (priv_set_t));
                return (EFAULT);
        }

        zone->zone_privset = privs;
        return (0);
}

/*
 * We make creative use of nvlists to pass in rctls from userland.  The list is
 * a list of the following structures:
 *
 * (name = rctl_name, value = nvpair_list_array)
 *
 * Where each element of the nvpair_list_array is of the form:
 *
 * [(name = "privilege", value = RCPRIV_PRIVILEGED),
 *      (name = "limit", value = uint64_t),
 *      (name = "action", value = (RCTL_LOCAL_NOACTION || RCTL_LOCAL_DENY))]
 */
static int
parse_rctls(caddr_t ubuf, size_t buflen, nvlist_t **nvlp)
{
        nvpair_t *nvp = NULL;
        nvlist_t *nvl = NULL;
        char *kbuf;
        int error;
        rctl_val_t rv;

        *nvlp = NULL;

        if (buflen == 0)
                return (0);

        if ((kbuf = kmem_alloc(buflen, KM_NOSLEEP)) == NULL)
                return (ENOMEM);
        if (copyin(ubuf, kbuf, buflen)) {
                error = EFAULT;
                goto out;
        }
        if (nvlist_unpack(kbuf, buflen, &nvl, KM_SLEEP) != 0) {
                /*
                 * nvl may have been allocated/free'd, but the value set to
                 * non-NULL, so we reset it here.
                 */
                nvl = NULL;
                error = EINVAL;
                goto out;
        }
        while ((nvp = nvlist_next_nvpair(nvl, nvp)) != NULL) {
                rctl_dict_entry_t *rde;
                rctl_hndl_t hndl;
                nvlist_t **nvlarray;
                uint_t i, nelem;
                char *name;

                error = EINVAL;
                name = nvpair_name(nvp);
                if (strncmp(nvpair_name(nvp), "zone.", sizeof ("zone.") - 1)
                    != 0 || nvpair_type(nvp) != DATA_TYPE_NVLIST_ARRAY) {
                        goto out;
                }
                if ((hndl = rctl_hndl_lookup(name)) == -1) {
                        goto out;
                }
                rde = rctl_dict_lookup_hndl(hndl);
                error = nvpair_value_nvlist_array(nvp, &nvlarray, &nelem);
                ASSERT(error == 0);
                for (i = 0; i < nelem; i++) {
                        if (error = nvlist2rctlval(nvlarray[i], &rv))
                                goto out;
                }
                if (rctl_invalid_value(rde, &rv)) {
                        error = EINVAL;
                        goto out;
                }
        }
        error = 0;
        *nvlp = nvl;
out:
        kmem_free(kbuf, buflen);
        if (error && nvl != NULL)
                nvlist_free(nvl);
        return (error);
}

int
zone_create_error(int er_error, int er_ext, int *er_out)
{
        if (er_out != NULL) {
                if (copyout(&er_ext, er_out, sizeof (int))) {
                        return (set_errno(EFAULT));
                }
        }
        return (set_errno(er_error));
}

/*
 * Parses a comma-separated list of ZFS datasets into a per-zone dictionary.
 */
static int
parse_zfs(zone_t *zone, caddr_t ubuf, size_t buflen)
{
        char *kbuf;
        char *dataset, *next;
        zone_dataset_t *zd;
        size_t len;

        if (ubuf == NULL || buflen == 0)
                return (0);

        if ((kbuf = kmem_alloc(buflen, KM_NOSLEEP)) == NULL)
                return (ENOMEM);

        if (copyin(ubuf, kbuf, buflen) != 0) {
                kmem_free(kbuf, buflen);
                return (EFAULT);
        }

        dataset = next = kbuf;
        for (;;) {
                zd = kmem_alloc(sizeof (zone_dataset_t), KM_SLEEP);

                next = strchr(dataset, ',');

                if (next == NULL)
                        len = strlen(dataset);
                else
                        len = next - dataset;

                zd->zd_dataset = kmem_alloc(len + 1, KM_SLEEP);
                bcopy(dataset, zd->zd_dataset, len);
                zd->zd_dataset[len] = '\0';

                list_insert_head(&zone->zone_datasets, zd);

                if (next == NULL)
                        break;

                dataset = next + 1;
        }

        kmem_free(kbuf, buflen);
        return (0);
}

/*
 * System call to create/initialize a new zone named 'zone_name', rooted
 * at 'zone_root', with a zone-wide privilege limit set of 'zone_privs',
 * and initialized with the zone-wide rctls described in 'rctlbuf'.
 *
 * If extended error is non-null, we may use it to return more detailed
 * error information.
 */
static zoneid_t
zone_create(const char *zone_name, const char *zone_root,
    const priv_set_t *zone_privs, size_t zone_privssz,
    caddr_t rctlbuf, size_t rctlbufsz,
    caddr_t zfsbuf, size_t zfsbufsz, int *extended_error,
    int flags)
{
        struct zsched_arg zarg;
        nvlist_t *rctls = NULL;
        proc_t *pp = curproc;
        zone_t *zone, *ztmp;
        zoneid_t zoneid, start = GLOBAL_ZONEID;
        int error;
        int error2 = 0;
        char *str;
        cred_t *zkcr;

        if (secpolicy_zone_config(CRED()) != 0)
                return (set_errno(EPERM));

        /* can't boot zone from within chroot environment */
        if (PTOU(pp)->u_rdir != NULL && PTOU(pp)->u_rdir != rootdir)
                return (zone_create_error(ENOTSUP, ZE_CHROOTED,
                    extended_error));
        /*
         * As the first step of zone creation, we want to allocate a zoneid.
         * This allocation is complicated by the fact that netstacks use the
         * zoneid to determine their stackid, but netstacks themselves are
         * freed asynchronously with respect to zone destruction.  This means
         * that a netstack reference leak (or in principle, an extraordinarily
         * long netstack reference hold) could result in a zoneid being
         * allocated that in fact corresponds to a stackid from an active
         * (referenced) netstack -- unleashing all sorts of havoc when that
         * netstack is actually (re)used.  (In the abstract, we might wish a
         * zoneid to not be deallocated until its last referencing netstack
         * has been released, but netstacks lack a backpointer into their
         * referencing zone -- and changing them to have such a pointer would
         * be substantial, to put it euphemistically.)  To avoid this, we
         * detect this condition on allocation: if we have allocated a zoneid
         * that corresponds to a netstack that's still in use, we warn about
         * it (as it is much more likely to be a reference leak than an actual
         * netstack reference), free it, and allocate another.  That these
         * identifers are allocated out of an ID space assures that we won't
         * see the identifier we just allocated.
         */
        for (;;) {
                zoneid = id_alloc(zoneid_space);

                if (!netstack_inuse_by_stackid(zoneid_to_netstackid(zoneid)))
                        break;

                id_free(zoneid_space, zoneid);

                if (start == GLOBAL_ZONEID) {
                        start = zoneid;
                } else if (zoneid == start) {
                        /*
                         * We have managed to iterate over the entire available
                         * zoneid space -- there are no identifiers available,
                         * presumably due to some number of leaked netstack
                         * references.  While it's in principle possible for us
                         * to continue to try, it seems wiser to give up at
                         * this point to warn and fail explicitly with a
                         * distinctive error.
                         */
                        cmn_err(CE_WARN, "zone_create() failed: all available "
                            "zone IDs have netstacks still in use");
                        return (set_errno(ENFILE));
                }

                cmn_err(CE_WARN, "unable to reuse zone ID %d; "
                    "netstack still in use", zoneid);
        }

        zone = kmem_zalloc(sizeof (zone_t), KM_SLEEP);
        zone->zone_id = zoneid;
        zone->zone_status = ZONE_IS_UNINITIALIZED;
        zone->zone_pool = pool_default;
        zone->zone_pool_mod = gethrtime();
        zone->zone_psetid = ZONE_PS_INVAL;
        zone->zone_ncpus = 0;
        zone->zone_ncpus_online = 0;
        zone->zone_restart_init = B_TRUE;
        zone->zone_brand = &native_brand;
        zone->zone_initname = NULL;
        mutex_init(&zone->zone_lock, NULL, MUTEX_DEFAULT, NULL);
        mutex_init(&zone->zone_nlwps_lock, NULL, MUTEX_DEFAULT, NULL);
        mutex_init(&zone->zone_mem_lock, NULL, MUTEX_DEFAULT, NULL);
        cv_init(&zone->zone_cv, NULL, CV_DEFAULT, NULL);
        list_create(&zone->zone_ref_list, sizeof (zone_ref_t),
            offsetof(zone_ref_t, zref_linkage));
        list_create(&zone->zone_zsd, sizeof (struct zsd_entry),
            offsetof(struct zsd_entry, zsd_linkage));
        list_create(&zone->zone_datasets, sizeof (zone_dataset_t),
            offsetof(zone_dataset_t, zd_linkage));
        list_create(&zone->zone_dl_list, sizeof (zone_dl_t),
            offsetof(zone_dl_t, zdl_linkage));
        rw_init(&zone->zone_mntfs_db_lock, NULL, RW_DEFAULT, NULL);

        if (flags & ZCF_NET_EXCL) {
                zone->zone_flags |= ZF_NET_EXCL;
        }

        if ((error = zone_set_name(zone, zone_name)) != 0) {
                zone_free(zone);
                return (zone_create_error(error, 0, extended_error));
        }

        if ((error = zone_set_root(zone, zone_root)) != 0) {
                zone_free(zone);
                return (zone_create_error(error, 0, extended_error));
        }
        if ((error = zone_set_privset(zone, zone_privs, zone_privssz)) != 0) {
                zone_free(zone);
                return (zone_create_error(error, 0, extended_error));
        }

        /* initialize node name to be the same as zone name */
        zone->zone_nodename = kmem_alloc(_SYS_NMLN, KM_SLEEP);
        (void) strncpy(zone->zone_nodename, zone->zone_name, _SYS_NMLN);
        zone->zone_nodename[_SYS_NMLN - 1] = '\0';

        zone->zone_domain = kmem_alloc(_SYS_NMLN, KM_SLEEP);
        zone->zone_domain[0] = '\0';
        zone->zone_hostid = HW_INVALID_HOSTID;
        zone->zone_shares = 1;
        zone->zone_shmmax = 0;
        zone->zone_ipc.ipcq_shmmni = 0;
        zone->zone_ipc.ipcq_semmni = 0;
        zone->zone_ipc.ipcq_msgmni = 0;
        zone->zone_bootargs = NULL;
        zone->zone_fs_allowed = NULL;

        secflags_zero(&zone0.zone_secflags.psf_lower);
        secflags_zero(&zone0.zone_secflags.psf_effective);
        secflags_zero(&zone0.zone_secflags.psf_inherit);
        secflags_fullset(&zone0.zone_secflags.psf_upper);

        zone->zone_initname =
            kmem_alloc(strlen(zone_default_initname) + 1, KM_SLEEP);
        (void) strcpy(zone->zone_initname, zone_default_initname);
        zone->zone_nlwps = 0;
        zone->zone_nlwps_ctl = INT_MAX;
        zone->zone_nprocs = 0;
        zone->zone_nprocs_ctl = INT_MAX;
        zone->zone_locked_mem = 0;
        zone->zone_locked_mem_ctl = UINT64_MAX;
        zone->zone_max_swap = 0;
        zone->zone_max_swap_ctl = UINT64_MAX;
        zone->zone_max_lofi = 0;
        zone->zone_max_lofi_ctl = UINT64_MAX;
        zone0.zone_lockedmem_kstat = NULL;
        zone0.zone_swapresv_kstat = NULL;

        /*
         * Zsched initializes the rctls.
         */
        zone->zone_rctls = NULL;

        if ((error = parse_rctls(rctlbuf, rctlbufsz, &rctls)) != 0) {
                zone_free(zone);
                return (zone_create_error(error, 0, extended_error));
        }

        if ((error = parse_zfs(zone, zfsbuf, zfsbufsz)) != 0) {
                zone_free(zone);
                return (set_errno(error));
        }

        /*
         * Stop all lwps since that's what normally happens as part of fork().
         * This needs to happen before we grab any locks to avoid deadlock
         * (another lwp in the process could be waiting for the held lock).
         */
        if (curthread != pp->p_agenttp && !holdlwps(SHOLDFORK)) {
                zone_free(zone);
                nvlist_free(rctls);
                return (zone_create_error(error, 0, extended_error));
        }

        if (block_mounts(zone) == 0) {
                mutex_enter(&pp->p_lock);
                if (curthread != pp->p_agenttp)
                        continuelwps(pp);
                mutex_exit(&pp->p_lock);
                zone_free(zone);
                nvlist_free(rctls);
                return (zone_create_error(error, 0, extended_error));
        }

        /*
         * Set up credential for kernel access.  After this, any errors
         * should go through the dance in errout rather than calling
         * zone_free directly.
         */
        zone->zone_kcred = crdup(kcred);
        crsetzone(zone->zone_kcred, zone);
        priv_intersect(zone->zone_privset, &CR_PPRIV(zone->zone_kcred));
        priv_intersect(zone->zone_privset, &CR_EPRIV(zone->zone_kcred));
        priv_intersect(zone->zone_privset, &CR_IPRIV(zone->zone_kcred));
        priv_intersect(zone->zone_privset, &CR_LPRIV(zone->zone_kcred));

        mutex_enter(&zonehash_lock);
        /*
         * Make sure zone doesn't already exist.
         */
        if ((ztmp = zone_find_all_by_name(zone->zone_name)) != NULL) {
                zone_status_t status;

                status = zone_status_get(ztmp);
                if (status == ZONE_IS_READY || status == ZONE_IS_RUNNING)
                        error = EEXIST;
                else
                        error = EBUSY;

                goto errout;
        }

        /*
         * Don't allow zone creations which would cause one zone's rootpath to
         * be accessible from that of another (non-global) zone.
         */
        if (zone_is_nested(zone->zone_rootpath)) {
                error = EBUSY;
                goto errout;
        }

        ASSERT(zonecount != 0);         /* check for leaks */
        if (zonecount + 1 > maxzones) {
                error = ENOMEM;
                goto errout;
        }

        if (zone_mount_count(zone->zone_rootpath) != 0) {
                error = EBUSY;
                error2 = ZE_AREMOUNTS;
                goto errout;
        }

        /*
         * Zone is still incomplete, but we need to drop all locks while
         * zsched() initializes this zone's kernel process.  We
         * optimistically add the zone to the hashtable and associated
         * lists so a parallel zone_create() doesn't try to create the
         * same zone.
         */
        zonecount++;
        (void) mod_hash_insert(zonehashbyid,
            (mod_hash_key_t)(uintptr_t)zone->zone_id,
            (mod_hash_val_t)(uintptr_t)zone);
        str = kmem_alloc(strlen(zone->zone_name) + 1, KM_SLEEP);
        (void) strcpy(str, zone->zone_name);
        (void) mod_hash_insert(zonehashbyname, (mod_hash_key_t)str,
            (mod_hash_val_t)(uintptr_t)zone);

        /*
         * Insert into active list.  At this point there are no 'hold's
         * on the zone, but everyone else knows not to use it, so we can
         * continue to use it.  zsched() will do a zone_hold() if the
         * newproc() is successful.
         */
        list_insert_tail(&zone_active, zone);
        mutex_exit(&zonehash_lock);

        zarg.zone = zone;
        zarg.nvlist = rctls;
        /*
         * The process, task, and project rctls are probably wrong;
         * we need an interface to get the default values of all rctls,
         * and initialize zsched appropriately.  I'm not sure that that
         * makes much of a difference, though.
         */
        error = newproc(zsched, (void *)&zarg, syscid, minclsyspri, NULL, 0);
        if (error != 0) {
                /*
                 * We need to undo all globally visible state.
                 */
                mutex_enter(&zonehash_lock);
                list_remove(&zone_active, zone);
                (void) mod_hash_destroy(zonehashbyname,
                    (mod_hash_key_t)(uintptr_t)zone->zone_name);
                (void) mod_hash_destroy(zonehashbyid,
                    (mod_hash_key_t)(uintptr_t)zone->zone_id);
                ASSERT(zonecount > 1);
                zonecount--;
                goto errout;
        }

        /*
         * Zone creation can't fail from now on.
         */

        /*
         * Create zone kstats
         */
        zone_kstat_create(zone);

        /*
         * Let the other lwps continue.
         */
        mutex_enter(&pp->p_lock);
        if (curthread != pp->p_agenttp)
                continuelwps(pp);
        mutex_exit(&pp->p_lock);

        /*
         * Wait for zsched to finish initializing the zone.
         */
        zone_status_wait(zone, ZONE_IS_READY);
        /*
         * The zone is fully visible, so we can let mounts progress.
         */
        resume_mounts(zone);
        nvlist_free(rctls);

        return (zoneid);

errout:
        mutex_exit(&zonehash_lock);
        /*
         * Let the other lwps continue.
         */
        mutex_enter(&pp->p_lock);
        if (curthread != pp->p_agenttp)
                continuelwps(pp);
        mutex_exit(&pp->p_lock);

        resume_mounts(zone);
        nvlist_free(rctls);
        /*
         * There is currently one reference to the zone, a cred_ref from
         * zone_kcred.  To free the zone, we call crfree, which will call
         * zone_cred_rele, which will call zone_free.
         */
        ASSERT(zone->zone_cred_ref == 1);
        ASSERT(zone->zone_kcred->cr_ref == 1);
        ASSERT(zone->zone_ref == 0);
        zkcr = zone->zone_kcred;
        zone->zone_kcred = NULL;
        crfree(zkcr);                           /* triggers call to zone_free */
        return (zone_create_error(error, error2, extended_error));
}

/*
 * Cause the zone to boot.  This is pretty simple, since we let zoneadmd do
 * the heavy lifting.  initname is the path to the program to launch
 * at the "top" of the zone; if this is NULL, we use the system default,
 * which is stored at zone_default_initname.
 */
static int
zone_boot(zoneid_t zoneid)
{
        int err;
        zone_t *zone;

        if (secpolicy_zone_config(CRED()) != 0)
                return (set_errno(EPERM));
        if (zoneid < MIN_USERZONEID || zoneid > MAX_ZONEID)
                return (set_errno(EINVAL));

        mutex_enter(&zonehash_lock);
        /*
         * Look for zone under hash lock to prevent races with calls to
         * zone_shutdown, zone_destroy, etc.
         */
        if ((zone = zone_find_all_by_id(zoneid)) == NULL) {
                mutex_exit(&zonehash_lock);
                return (set_errno(EINVAL));
        }

        mutex_enter(&zone_status_lock);
        if (zone_status_get(zone) != ZONE_IS_READY) {
                mutex_exit(&zone_status_lock);
                mutex_exit(&zonehash_lock);
                return (set_errno(EINVAL));
        }
        zone_status_set(zone, ZONE_IS_BOOTING);
        mutex_exit(&zone_status_lock);

        zone_hold(zone);        /* so we can use the zone_t later */
        mutex_exit(&zonehash_lock);

        if (zone_status_wait_sig(zone, ZONE_IS_RUNNING) == 0) {
                zone_rele(zone);
                return (set_errno(EINTR));
        }

        /*
         * Boot (starting init) might have failed, in which case the zone
         * will go to the SHUTTING_DOWN state; an appropriate errno will
         * be placed in zone->zone_boot_err, and so we return that.
         */
        err = zone->zone_boot_err;
        zone_rele(zone);
        return (err ? set_errno(err) : 0);
}

/*
 * Kills all user processes in the zone, waiting for them all to exit
 * before returning.
 */
static int
zone_empty(zone_t *zone)
{
        int waitstatus;

        /*
         * We need to drop zonehash_lock before killing all
         * processes, otherwise we'll deadlock with zone_find_*
         * which can be called from the exit path.
         */
        ASSERT(MUTEX_NOT_HELD(&zonehash_lock));
        while ((waitstatus = zone_status_timedwait_sig(zone,
            ddi_get_lbolt() + hz, ZONE_IS_EMPTY)) == -1) {
                killall(zone->zone_id);
        }
        /*
         * return EINTR if we were signaled
         */
        if (waitstatus == 0)
                return (EINTR);
        return (0);
}

/*
 * This function implements the policy for zone visibility. A non-global zone
 * can only see itself.
 *
 * Returns true if zone attributes are viewable, false otherwise.
 */
static boolean_t
zone_list_access(zone_t *zone)
{

        if (curproc->p_zone == global_zone ||
            curproc->p_zone == zone) {
                return (B_TRUE);
        } else {
                return (B_FALSE);
        }
}

/*
 * Systemcall to start the zone's halt sequence.  By the time this
 * function successfully returns, all user processes and kernel threads
 * executing in it will have exited, ZSD shutdown callbacks executed,
 * and the zone status set to ZONE_IS_DOWN.
 *
 * It is possible that the call will interrupt itself if the caller is the
 * parent of any process running in the zone, and doesn't have SIGCHLD blocked.
 */
static int
zone_shutdown(zoneid_t zoneid)
{
        int error;
        zone_t *zone;
        zone_status_t status;

        if (secpolicy_zone_config(CRED()) != 0)
                return (set_errno(EPERM));
        if (zoneid < MIN_USERZONEID || zoneid > MAX_ZONEID)
                return (set_errno(EINVAL));

        mutex_enter(&zonehash_lock);
        /*
         * Look for zone under hash lock to prevent races with other
         * calls to zone_shutdown and zone_destroy.
         */
        if ((zone = zone_find_all_by_id(zoneid)) == NULL) {
                mutex_exit(&zonehash_lock);
                return (set_errno(EINVAL));
        }

        /*
         * We have to drop zonehash_lock before calling block_mounts.
         * Hold the zone so we can continue to use the zone_t.
         */
        zone_hold(zone);
        mutex_exit(&zonehash_lock);

        /*
         * Block mounts so that VFS_MOUNT() can get an accurate view of
         * the zone's status with regards to ZONE_IS_SHUTTING down.
         *
         * e.g. NFS can fail the mount if it determines that the zone
         * has already begun the shutdown sequence.
         *
         */
        if (block_mounts(zone) == 0) {
                zone_rele(zone);
                return (set_errno(EINTR));
        }

        mutex_enter(&zonehash_lock);
        mutex_enter(&zone_status_lock);
        status = zone_status_get(zone);
        /*
         * Fail if the zone isn't fully initialized yet.
         */
        if (status < ZONE_IS_READY) {
                mutex_exit(&zone_status_lock);
                mutex_exit(&zonehash_lock);
                resume_mounts(zone);
                zone_rele(zone);
                return (set_errno(EINVAL));
        }
        /*
         * If conditions required for zone_shutdown() to return have been met,
         * return success.
         */
        if (status >= ZONE_IS_DOWN) {
                mutex_exit(&zone_status_lock);
                mutex_exit(&zonehash_lock);
                resume_mounts(zone);
                zone_rele(zone);
                return (0);
        }
        /*
         * If zone_shutdown() hasn't been called before, go through the motions.
         * If it has, there's nothing to do but wait for the kernel threads to
         * drain.
         */
        if (status < ZONE_IS_EMPTY) {
                uint_t ntasks;

                mutex_enter(&zone->zone_lock);
                if ((ntasks = zone->zone_ntasks) != 1) {
                        /*
                         * There's still stuff running.
                         */
                        zone_status_set(zone, ZONE_IS_SHUTTING_DOWN);
                }
                mutex_exit(&zone->zone_lock);
                if (ntasks == 1) {
                        /*
                         * The only way to create another task is through
                         * zone_enter(), which will block until we drop
                         * zonehash_lock.  The zone is empty.
                         */
                        if (zone->zone_kthreads == NULL) {
                                /*
                                 * Skip ahead to ZONE_IS_DOWN
                                 */
                                zone_status_set(zone, ZONE_IS_DOWN);
                        } else {
                                zone_status_set(zone, ZONE_IS_EMPTY);
                        }
                }
        }
        mutex_exit(&zone_status_lock);
        mutex_exit(&zonehash_lock);
        resume_mounts(zone);

        if (error = zone_empty(zone)) {
                zone_rele(zone);
                return (set_errno(error));
        }
        /*
         * After the zone status goes to ZONE_IS_DOWN this zone will no
         * longer be notified of changes to the pools configuration, so
         * in order to not end up with a stale pool pointer, we point
         * ourselves at the default pool and remove all resource
         * visibility.  This is especially important as the zone_t may
         * languish on the deathrow for a very long time waiting for
         * cred's to drain out.
         *
         * This rebinding of the zone can happen multiple times
         * (presumably due to interrupted or parallel systemcalls)
         * without any adverse effects.
         */
        if (pool_lock_intr() != 0) {
                zone_rele(zone);
                return (set_errno(EINTR));
        }
        if (pool_state == POOL_ENABLED) {
                mutex_enter(&cpu_lock);
                zone_pool_set(zone, pool_default);
                /*
                 * The zone no longer needs to be able to see any cpus.
                 */
                zone_pset_set(zone, ZONE_PS_INVAL);
                mutex_exit(&cpu_lock);
        }
        pool_unlock();

        /*
         * ZSD shutdown callbacks can be executed multiple times, hence
         * it is safe to not be holding any locks across this call.
         */
        zone_zsd_callbacks(zone, ZSD_SHUTDOWN);

        mutex_enter(&zone_status_lock);
        if (zone->zone_kthreads == NULL && zone_status_get(zone) < ZONE_IS_DOWN)
                zone_status_set(zone, ZONE_IS_DOWN);
        mutex_exit(&zone_status_lock);

        /*
         * Wait for kernel threads to drain.
         */
        if (!zone_status_wait_sig(zone, ZONE_IS_DOWN)) {
                zone_rele(zone);
                return (set_errno(EINTR));
        }

        /*
         * Zone can be become down/destroyable even if the above wait
         * returns EINTR, so any code added here may never execute.
         * (i.e. don't add code here)
         */

        zone_rele(zone);
        return (0);
}

/*
 * Log the specified zone's reference counts.  The caller should not be
 * holding the zone's zone_lock.
 */
static void
zone_log_refcounts(zone_t *zone)
{
        char *buffer;
        char *buffer_position;
        uint32_t buffer_size;
        uint32_t index;
        uint_t ref;
        uint_t cred_ref;

        /*
         * Construct a string representing the subsystem-specific reference
         * counts.  The counts are printed in ascending order by index into the
         * zone_t::zone_subsys_ref array.  The list will be surrounded by
         * square brackets [] and will only contain nonzero reference counts.
         *
         * The buffer will hold two square bracket characters plus ten digits,
         * one colon, one space, one comma, and some characters for a
         * subsystem name per subsystem-specific reference count.  (Unsigned 32-
         * bit integers have at most ten decimal digits.)  The last
         * reference count's comma is replaced by the closing square
         * bracket and a NULL character to terminate the string.
         *
         * NOTE: We have to grab the zone's zone_lock to create a consistent
         * snapshot of the zone's reference counters.
         *
         * First, figure out how much space the string buffer will need.
         * The buffer's size is stored in buffer_size.
         */
        buffer_size = 2;                        /* for the square brackets */
        mutex_enter(&zone->zone_lock);
        zone->zone_flags |= ZF_REFCOUNTS_LOGGED;
        ref = zone->zone_ref;
        cred_ref = zone->zone_cred_ref;
        for (index = 0; index < ZONE_REF_NUM_SUBSYS; ++index)
                if (zone->zone_subsys_ref[index] != 0)
                        buffer_size += strlen(zone_ref_subsys_names[index]) +
                            13;
        if (buffer_size == 2) {
                /*
                 * No subsystems had nonzero reference counts.  Don't bother
                 * with allocating a buffer; just log the general-purpose and
                 * credential reference counts.
                 */
                mutex_exit(&zone->zone_lock);
                (void) strlog(0, 0, 1, SL_CONSOLE | SL_NOTE,
                    "Zone '%s' (ID: %d) is shutting down, but %u zone "
                    "references and %u credential references are still extant",
                    zone->zone_name, zone->zone_id, ref, cred_ref);
                return;
        }

        /*
         * buffer_size contains the exact number of characters that the
         * buffer will need.  Allocate the buffer and fill it with nonzero
         * subsystem-specific reference counts.  Surround the results with
         * square brackets afterwards.
         */
        buffer = kmem_alloc(buffer_size, KM_SLEEP);
        buffer_position = &buffer[1];
        for (index = 0; index < ZONE_REF_NUM_SUBSYS; ++index) {
                /*
                 * NOTE: The DDI's version of sprintf() returns a pointer to
                 * the modified buffer rather than the number of bytes written
                 * (as in snprintf(3C)).  This is unfortunate and annoying.
                 * Therefore, we'll use snprintf() with INT_MAX to get the
                 * number of bytes written.  Using INT_MAX is safe because
                 * the buffer is perfectly sized for the data: we'll never
                 * overrun the buffer.
                 */
                if (zone->zone_subsys_ref[index] != 0)
                        buffer_position += snprintf(buffer_position, INT_MAX,
                            "%s: %u,", zone_ref_subsys_names[index],
                            zone->zone_subsys_ref[index]);
        }
        mutex_exit(&zone->zone_lock);
        buffer[0] = '[';
        ASSERT((uintptr_t)(buffer_position - buffer) < buffer_size);
        ASSERT(buffer_position[0] == '\0' && buffer_position[-1] == ',');
        buffer_position[-1] = ']';

        /*
         * Log the reference counts and free the message buffer.
         */
        (void) strlog(0, 0, 1, SL_CONSOLE | SL_NOTE,
            "Zone '%s' (ID: %d) is shutting down, but %u zone references and "
            "%u credential references are still extant %s", zone->zone_name,
            zone->zone_id, ref, cred_ref, buffer);
        kmem_free(buffer, buffer_size);
}

/*
 * Systemcall entry point to finalize the zone halt process.  The caller
 * must have already successfully called zone_shutdown().
 *
 * Upon successful completion, the zone will have been fully destroyed:
 * zsched will have exited, destructor callbacks executed, and the zone
 * removed from the list of active zones.
 */
static int
zone_destroy(zoneid_t zoneid)
{
        uint64_t uniqid;
        zone_t *zone;
        zone_status_t status;
        clock_t wait_time;
        boolean_t log_refcounts;

        if (secpolicy_zone_config(CRED()) != 0)
                return (set_errno(EPERM));
        if (zoneid < MIN_USERZONEID || zoneid > MAX_ZONEID)
                return (set_errno(EINVAL));

        mutex_enter(&zonehash_lock);
        /*
         * Look for zone under hash lock to prevent races with other
         * calls to zone_destroy.
         */
        if ((zone = zone_find_all_by_id(zoneid)) == NULL) {
                mutex_exit(&zonehash_lock);
                return (set_errno(EINVAL));
        }

        if (zone_mount_count(zone->zone_rootpath) != 0) {
                mutex_exit(&zonehash_lock);
                return (set_errno(EBUSY));
        }
        mutex_enter(&zone_status_lock);
        status = zone_status_get(zone);
        if (status < ZONE_IS_DOWN) {
                mutex_exit(&zone_status_lock);
                mutex_exit(&zonehash_lock);
                return (set_errno(EBUSY));
        } else if (status == ZONE_IS_DOWN) {
                zone_status_set(zone, ZONE_IS_DYING); /* Tell zsched to exit */
        }
        mutex_exit(&zone_status_lock);
        zone_hold(zone);
        mutex_exit(&zonehash_lock);

        /*
         * wait for zsched to exit
         */
        zone_status_wait(zone, ZONE_IS_DEAD);
        zone_zsd_callbacks(zone, ZSD_DESTROY);
        zone->zone_netstack = NULL;
        uniqid = zone->zone_uniqid;
        zone_rele(zone);
        zone = NULL;    /* potentially free'd */

        log_refcounts = B_FALSE;
        wait_time = SEC_TO_TICK(ZONE_DESTROY_TIMEOUT_SECS);
        mutex_enter(&zonehash_lock);
        for (; /* ever */; ) {
                boolean_t unref;
                boolean_t refs_have_been_logged;

                if ((zone = zone_find_all_by_id(zoneid)) == NULL ||
                    zone->zone_uniqid != uniqid) {
                        /*
                         * The zone has gone away.  Necessary conditions
                         * are met, so we return success.
                         */
                        mutex_exit(&zonehash_lock);
                        return (0);
                }
                mutex_enter(&zone->zone_lock);
                unref = ZONE_IS_UNREF(zone);
                refs_have_been_logged = (zone->zone_flags &
                    ZF_REFCOUNTS_LOGGED);
                mutex_exit(&zone->zone_lock);
                if (unref) {
                        /*
                         * There is only one reference to the zone -- that
                         * added when the zone was added to the hashtables --
                         * and things will remain this way until we drop
                         * zonehash_lock... we can go ahead and cleanup the
                         * zone.
                         */
                        break;
                }

                /*
                 * Wait for zone_rele_common() or zone_cred_rele() to signal
                 * zone_destroy_cv.  zone_destroy_cv is signaled only when
                 * some zone's general-purpose reference count reaches one.
                 * If ZONE_DESTROY_TIMEOUT_SECS seconds elapse while waiting
                 * on zone_destroy_cv, then log the zone's reference counts and
                 * continue to wait for zone_rele() and zone_cred_rele().
                 */
                if (!refs_have_been_logged) {
                        if (!log_refcounts) {
                                /*
                                 * This thread hasn't timed out waiting on
                                 * zone_destroy_cv yet.  Wait wait_time clock
                                 * ticks (initially ZONE_DESTROY_TIMEOUT_SECS
                                 * seconds) for the zone's references to clear.
                                 */
                                ASSERT(wait_time > 0);
                                wait_time = cv_reltimedwait_sig(
                                    &zone_destroy_cv, &zonehash_lock, wait_time,
                                    TR_SEC);
                                if (wait_time > 0) {
                                        /*
                                         * A thread in zone_rele() or
                                         * zone_cred_rele() signaled
                                         * zone_destroy_cv before this thread's
                                         * wait timed out.  The zone might have
                                         * only one reference left; find out!
                                         */
                                        continue;
                                } else if (wait_time == 0) {
                                        /* The thread's process was signaled. */
                                        mutex_exit(&zonehash_lock);
                                        return (set_errno(EINTR));
                                }

                                /*
                                 * The thread timed out while waiting on
                                 * zone_destroy_cv.  Even though the thread
                                 * timed out, it has to check whether another
                                 * thread woke up from zone_destroy_cv and
                                 * destroyed the zone.
                                 *
                                 * If the zone still exists and has more than
                                 * one unreleased general-purpose reference,
                                 * then log the zone's reference counts.
                                 */
                                log_refcounts = B_TRUE;
                                continue;
                        }

                        /*
                         * The thread already timed out on zone_destroy_cv while
                         * waiting for subsystems to release the zone's last
                         * general-purpose references.  Log the zone's reference
                         * counts and wait indefinitely on zone_destroy_cv.
                         */
                        zone_log_refcounts(zone);
                }
                if (cv_wait_sig(&zone_destroy_cv, &zonehash_lock) == 0) {
                        /* The thread's process was signaled. */
                        mutex_exit(&zonehash_lock);
                        return (set_errno(EINTR));
                }
        }

        /*
         * Remove CPU cap for this zone now since we're not going to
         * fail below this point.
         */
        cpucaps_zone_remove(zone);

        /* Get rid of the zone's kstats */
        zone_kstat_delete(zone);

        /* remove the pfexecd doors */
        if (zone->zone_pfexecd != NULL) {
                klpd_freelist(&zone->zone_pfexecd);
                zone->zone_pfexecd = NULL;
        }

        /* free brand specific data */
        if (ZONE_IS_BRANDED(zone))
                ZBROP(zone)->b_free_brand_data(zone);

        /* Say goodbye to brand framework. */
        brand_unregister_zone(zone->zone_brand);

        /*
         * It is now safe to let the zone be recreated; remove it from the
         * lists.  The memory will not be freed until the last cred
         * reference goes away.
         */
        ASSERT(zonecount > 1);  /* must be > 1; can't destroy global zone */
        zonecount--;
        /* remove from active list and hash tables */
        list_remove(&zone_active, zone);
        (void) mod_hash_destroy(zonehashbyname,
            (mod_hash_key_t)zone->zone_name);
        (void) mod_hash_destroy(zonehashbyid,
            (mod_hash_key_t)(uintptr_t)zone->zone_id);
        mutex_exit(&zonehash_lock);

        /*
         * Release the root vnode; we're not using it anymore.  Nor should any
         * other thread that might access it exist.
         */
        if (zone->zone_rootvp != NULL) {
                VN_RELE(zone->zone_rootvp);
                zone->zone_rootvp = NULL;
        }

        /* add to deathrow list */
        mutex_enter(&zone_deathrow_lock);
        list_insert_tail(&zone_deathrow, zone);
        mutex_exit(&zone_deathrow_lock);

        /*
         * Drop last reference (which was added by zsched()), this will
         * free the zone unless there are outstanding cred references.
         */
        zone_rele(zone);
        return (0);
}

/*
 * Systemcall entry point for zone_getattr(2).
 */
static ssize_t
zone_getattr(zoneid_t zoneid, int attr, void *buf, size_t bufsize)
{
        size_t size;
        int error = 0, err;
        zone_t *zone;
        char *zonepath;
        char *outstr;
        zone_status_t zone_status;
        pid_t initpid;
        boolean_t global = (curzone == global_zone);
        boolean_t inzone = (curzone->zone_id == zoneid);
        ushort_t flags;
        zone_net_data_t *zbuf;

        mutex_enter(&zonehash_lock);
        if ((zone = zone_find_all_by_id(zoneid)) == NULL) {
                mutex_exit(&zonehash_lock);
                return (set_errno(EINVAL));
        }
        zone_status = zone_status_get(zone);
        if (zone_status < ZONE_IS_INITIALIZED) {
                mutex_exit(&zonehash_lock);
                return (set_errno(EINVAL));
        }
        zone_hold(zone);
        mutex_exit(&zonehash_lock);

        /*
         * If not in the global zone, don't show information about other zones.
         */
        if (!zone_list_access(zone)) {
                zone_rele(zone);
                return (set_errno(EINVAL));
        }

        switch (attr) {
        case ZONE_ATTR_ROOT:
                if (global) {
                        /*
                         * Copy the path to trim the trailing "/" (except for
                         * the global zone).
                         */
                        if (zone != global_zone)
                                size = zone->zone_rootpathlen - 1;
                        else
                                size = zone->zone_rootpathlen;
                        zonepath = kmem_alloc(size, KM_SLEEP);
                        bcopy(zone->zone_rootpath, zonepath, size);
                        zonepath[size - 1] = '\0';
                } else {
                        if (inzone) {
                                /*
                                 * Caller is not in the global zone.  if the
                                 * query is on the current zone just return
                                 * faked-up path for current zone.
                                 */
                                zonepath = "/";
                                size = 2;
                        } else {
                                /*
                                 * Return related path for current zone.
                                 */
                                int prefix_len = strlen(zone_prefix);
                                int zname_len = strlen(zone->zone_name);

                                size = prefix_len + zname_len + 1;
                                zonepath = kmem_alloc(size, KM_SLEEP);
                                bcopy(zone_prefix, zonepath, prefix_len);
                                bcopy(zone->zone_name, zonepath +
                                    prefix_len, zname_len);
                                zonepath[size - 1] = '\0';
                        }
                }
                if (bufsize > size)
                        bufsize = size;
                if (buf != NULL) {
                        err = copyoutstr(zonepath, buf, bufsize, NULL);
                        if (err != 0 && err != ENAMETOOLONG)
                                error = EFAULT;
                }
                if (global)
                        kmem_free(zonepath, size);
                break;

        case ZONE_ATTR_NAME:
                size = strlen(zone->zone_name) + 1;
                if (bufsize > size)
                        bufsize = size;
                if (buf != NULL) {
                        err = copyoutstr(zone->zone_name, buf, bufsize, NULL);
                        if (err != 0 && err != ENAMETOOLONG)
                                error = EFAULT;
                }
                break;

        case ZONE_ATTR_STATUS:
                /*
                 * Since we're not holding zonehash_lock, the zone status
                 * may be anything; leave it up to userland to sort it out.
                 */
                size = sizeof (zone_status);
                if (bufsize > size)
                        bufsize = size;
                zone_status = zone_status_get(zone);
                if (buf != NULL &&
                    copyout(&zone_status, buf, bufsize) != 0)
                        error = EFAULT;
                break;
        case ZONE_ATTR_FLAGS:
                size = sizeof (zone->zone_flags);
                if (bufsize > size)
                        bufsize = size;
                flags = zone->zone_flags;
                if (buf != NULL &&
                    copyout(&flags, buf, bufsize) != 0)
                        error = EFAULT;
                break;
        case ZONE_ATTR_PRIVSET:
                size = sizeof (priv_set_t);
                if (bufsize > size)
                        bufsize = size;
                if (buf != NULL &&
                    copyout(zone->zone_privset, buf, bufsize) != 0)
                        error = EFAULT;
                break;
        case ZONE_ATTR_UNIQID:
                size = sizeof (zone->zone_uniqid);
                if (bufsize > size)
                        bufsize = size;
                if (buf != NULL &&
                    copyout(&zone->zone_uniqid, buf, bufsize) != 0)
                        error = EFAULT;
                break;
        case ZONE_ATTR_POOLID:
                {
                        pool_t *pool;
                        poolid_t poolid;

                        if (pool_lock_intr() != 0) {
                                error = EINTR;
                                break;
                        }
                        pool = zone_pool_get(zone);
                        poolid = pool->pool_id;
                        pool_unlock();
                        size = sizeof (poolid);
                        if (bufsize > size)
                                bufsize = size;
                        if (buf != NULL && copyout(&poolid, buf, size) != 0)
                                error = EFAULT;
                }
                break;
        case ZONE_ATTR_INITPID:
                size = sizeof (initpid);
                if (bufsize > size)
                        bufsize = size;
                initpid = zone->zone_proc_initpid;
                if (initpid == -1) {
                        error = ESRCH;
                        break;
                }
                if (buf != NULL &&
                    copyout(&initpid, buf, bufsize) != 0)
                        error = EFAULT;
                break;
        case ZONE_ATTR_BRAND:
                size = strlen(zone->zone_brand->b_name) + 1;

                if (bufsize > size)
                        bufsize = size;
                if (buf != NULL) {
                        err = copyoutstr(zone->zone_brand->b_name, buf,
                            bufsize, NULL);
                        if (err != 0 && err != ENAMETOOLONG)
                                error = EFAULT;
                }
                break;
        case ZONE_ATTR_INITNAME:
                size = strlen(zone->zone_initname) + 1;
                if (bufsize > size)
                        bufsize = size;
                if (buf != NULL) {
                        err = copyoutstr(zone->zone_initname, buf, bufsize,
                            NULL);
                        if (err != 0 && err != ENAMETOOLONG)
                                error = EFAULT;
                }
                break;
        case ZONE_ATTR_BOOTARGS:
                if (zone->zone_bootargs == NULL)
                        outstr = "";
                else
                        outstr = zone->zone_bootargs;
                size = strlen(outstr) + 1;
                if (bufsize > size)
                        bufsize = size;
                if (buf != NULL) {
                        err = copyoutstr(outstr, buf, bufsize, NULL);
                        if (err != 0 && err != ENAMETOOLONG)
                                error = EFAULT;
                }
                break;
        case ZONE_ATTR_PHYS_MCAP:
                size = sizeof (zone->zone_phys_mcap);
                if (bufsize > size)
                        bufsize = size;
                if (buf != NULL &&
                    copyout(&zone->zone_phys_mcap, buf, bufsize) != 0)
                        error = EFAULT;
                break;
        case ZONE_ATTR_SCHED_CLASS:
                mutex_enter(&class_lock);

                if (zone->zone_defaultcid >= loaded_classes)
                        outstr = "";
                else
                        outstr = sclass[zone->zone_defaultcid].cl_name;
                size = strlen(outstr) + 1;
                if (bufsize > size)
                        bufsize = size;
                if (buf != NULL) {
                        err = copyoutstr(outstr, buf, bufsize, NULL);
                        if (err != 0 && err != ENAMETOOLONG)
                                error = EFAULT;
                }

                mutex_exit(&class_lock);
                break;
        case ZONE_ATTR_HOSTID:
                if (zone->zone_hostid != HW_INVALID_HOSTID &&
                    bufsize == sizeof (zone->zone_hostid)) {
                        size = sizeof (zone->zone_hostid);
                        if (buf != NULL && copyout(&zone->zone_hostid, buf,
                            bufsize) != 0)
                                error = EFAULT;
                } else {
                        error = EINVAL;
                }
                break;
        case ZONE_ATTR_FS_ALLOWED:
                if (zone->zone_fs_allowed == NULL)
                        outstr = "";
                else
                        outstr = zone->zone_fs_allowed;
                size = strlen(outstr) + 1;
                if (bufsize > size)
                        bufsize = size;
                if (buf != NULL) {
                        err = copyoutstr(outstr, buf, bufsize, NULL);
                        if (err != 0 && err != ENAMETOOLONG)
                                error = EFAULT;
                }
                break;
        case ZONE_ATTR_SECFLAGS:
                size = sizeof (zone->zone_secflags);
                if (bufsize > size)
                        bufsize = size;
                if ((err = copyout(&zone->zone_secflags, buf, bufsize)) != 0)
                        error = EFAULT;
                break;
        case ZONE_ATTR_NETWORK:
                zbuf = kmem_alloc(bufsize, KM_SLEEP);
                if (copyin(buf, zbuf, bufsize) != 0) {
                        error = EFAULT;
                } else {
                        error = zone_get_network(zoneid, zbuf);
                        if (error == 0 && copyout(zbuf, buf, bufsize) != 0)
                                error = EFAULT;
                }
                kmem_free(zbuf, bufsize);
                break;
        default:
                if ((attr >= ZONE_ATTR_BRAND_ATTRS) && ZONE_IS_BRANDED(zone)) {
                        size = bufsize;
                        error = ZBROP(zone)->b_getattr(zone, attr, buf, &size);
                } else {
                        error = EINVAL;
                }
        }
        zone_rele(zone);

        if (error)
                return (set_errno(error));
        return ((ssize_t)size);
}

/*
 * Systemcall entry point for zone_setattr(2).
 */
/*ARGSUSED*/
static int
zone_setattr(zoneid_t zoneid, int attr, void *buf, size_t bufsize)
{
        zone_t *zone;
        zone_status_t zone_status;
        int err = -1;
        zone_net_data_t *zbuf;

        if (secpolicy_zone_config(CRED()) != 0)
                return (set_errno(EPERM));

        /*
         * Only the ZONE_ATTR_PHYS_MCAP attribute can be set on the
         * global zone.
         */
        if (zoneid == GLOBAL_ZONEID && attr != ZONE_ATTR_PHYS_MCAP) {
                return (set_errno(EINVAL));
        }

        mutex_enter(&zonehash_lock);
        if ((zone = zone_find_all_by_id(zoneid)) == NULL) {
                mutex_exit(&zonehash_lock);
                return (set_errno(EINVAL));
        }
        zone_hold(zone);
        mutex_exit(&zonehash_lock);

        /*
         * At present most attributes can only be set on non-running,
         * non-global zones.
         */
        zone_status = zone_status_get(zone);
        if (attr != ZONE_ATTR_PHYS_MCAP && zone_status > ZONE_IS_READY) {
                err = EINVAL;
                goto done;
        }

        switch (attr) {
        case ZONE_ATTR_INITNAME:
                err = zone_set_initname(zone, (const char *)buf);
                break;
        case ZONE_ATTR_INITNORESTART:
                zone->zone_restart_init = B_FALSE;
                err = 0;
                break;
        case ZONE_ATTR_BOOTARGS:
                err = zone_set_bootargs(zone, (const char *)buf);
                break;
        case ZONE_ATTR_BRAND:
                err = zone_set_brand(zone, (const char *)buf);
                break;
        case ZONE_ATTR_FS_ALLOWED:
                err = zone_set_fs_allowed(zone, (const char *)buf);
                break;
        case ZONE_ATTR_SECFLAGS:
                err = zone_set_secflags(zone, (psecflags_t *)buf);
                break;
        case ZONE_ATTR_PHYS_MCAP:
                err = zone_set_phys_mcap(zone, (const uint64_t *)buf);
                break;
        case ZONE_ATTR_SCHED_CLASS:
                err = zone_set_sched_class(zone, (const char *)buf);
                break;
        case ZONE_ATTR_HOSTID:
                if (bufsize == sizeof (zone->zone_hostid)) {
                        if (copyin(buf, &zone->zone_hostid, bufsize) == 0)
                                err = 0;
                        else
                                err = EFAULT;
                } else {
                        err = EINVAL;
                }
                break;
        case ZONE_ATTR_NETWORK:
                if (bufsize > (PIPE_BUF + sizeof (zone_net_data_t))) {
                        err = EINVAL;
                        break;
                }
                zbuf = kmem_alloc(bufsize, KM_SLEEP);
                if (copyin(buf, zbuf, bufsize) != 0) {
                        kmem_free(zbuf, bufsize);
                        err = EFAULT;
                        break;
                }
                err = zone_set_network(zoneid, zbuf);
                kmem_free(zbuf, bufsize);
                break;
        default:
                if ((attr >= ZONE_ATTR_BRAND_ATTRS) && ZONE_IS_BRANDED(zone))
                        err = ZBROP(zone)->b_setattr(zone, attr, buf, bufsize);
                else
                        err = EINVAL;
        }

done:
        zone_rele(zone);
        ASSERT(err != -1);
        return (err != 0 ? set_errno(err) : 0);
}

/*
 * Return zero if the process has at least one vnode mapped in to its
 * address space which shouldn't be allowed to change zones.
 *
 * Also return zero if the process has any shared mappings which reserve
 * swap.  This is because the counting for zone.max-swap does not allow swap
 * reservation to be shared between zones.  zone swap reservation is counted
 * on zone->zone_max_swap.
 */
static int
as_can_change_zones(void)
{
        proc_t *pp = curproc;
        struct seg *seg;
        struct as *as = pp->p_as;
        vnode_t *vp;
        int allow = 1;

        ASSERT(pp->p_as != &kas);
        AS_LOCK_ENTER(as, RW_READER);
        for (seg = AS_SEGFIRST(as); seg != NULL; seg = AS_SEGNEXT(as, seg)) {

                /*
                 * Cannot enter zone with shared anon memory which
                 * reserves swap.  See comment above.
                 */
                if (seg_can_change_zones(seg) == B_FALSE) {
                        allow = 0;
                        break;
                }
                /*
                 * if we can't get a backing vnode for this segment then skip
                 * it.
                 */
                vp = NULL;
                if (segop_getvp(seg, seg->s_base, &vp) != 0 || vp == NULL)
                        continue;
                if (!vn_can_change_zones(vp)) { /* bail on first match */
                        allow = 0;
                        break;
                }
        }
        AS_LOCK_EXIT(as);
        return (allow);
}

/*
 * Count swap reserved by curproc's address space
 */
static size_t
as_swresv(void)
{
        proc_t *pp = curproc;
        struct seg *seg;
        struct as *as = pp->p_as;
        size_t swap = 0;

        ASSERT(pp->p_as != &kas);
        ASSERT(AS_WRITE_HELD(as));
        for (seg = AS_SEGFIRST(as); seg != NULL; seg = AS_SEGNEXT(as, seg))
                swap += seg_swresv(seg);

        return (swap);
}

/*
 * Systemcall entry point for zone_enter().
 *
 * The current process is injected into said zone.  In the process
 * it will change its project membership, privileges, rootdir/cwd,
 * zone-wide rctls, and pool association to match those of the zone.
 *
 * The first zone_enter() called while the zone is in the ZONE_IS_READY
 * state will transition it to ZONE_IS_RUNNING.  Processes may only
 * enter a zone that is "ready" or "running".
 */
static int
zone_enter(zoneid_t zoneid)
{
        zone_t *zone;
        vnode_t *vp;
        proc_t *pp = curproc;
        contract_t *ct;
        cont_process_t *ctp;
        task_t *tk, *oldtk;
        kproject_t *zone_proj0;
        cred_t *cr, *newcr;
        pool_t *oldpool, *newpool;
        sess_t *sp;
        uid_t uid;
        zone_status_t status;
        int err = 0;
        rctl_entity_p_t e;
        size_t swap;
        kthread_id_t t;

        if (secpolicy_zone_config(CRED()) != 0)
                return (set_errno(EPERM));
        if (zoneid < MIN_USERZONEID || zoneid > MAX_ZONEID)
                return (set_errno(EINVAL));

        /*
         * Stop all lwps so we don't need to hold a lock to look at
         * curproc->p_zone.  This needs to happen before we grab any
         * locks to avoid deadlock (another lwp in the process could
         * be waiting for the held lock).
         */
        if (curthread != pp->p_agenttp && !holdlwps(SHOLDFORK))
                return (set_errno(EINTR));

        /*
         * Make sure we're not changing zones with files open or mapped in
         * to our address space which shouldn't be changing zones.
         */
        if (!files_can_change_zones()) {
                err = EBADF;
                goto out;
        }
        if (!as_can_change_zones()) {
                err = EFAULT;
                goto out;
        }

        mutex_enter(&zonehash_lock);
        if (pp->p_zone != global_zone) {
                mutex_exit(&zonehash_lock);
                err = EINVAL;
                goto out;
        }

        zone = zone_find_all_by_id(zoneid);
        if (zone == NULL) {
                mutex_exit(&zonehash_lock);
                err = EINVAL;
                goto out;
        }

        /*
         * To prevent processes in a zone from holding contracts on
         * extrazonal resources, and to avoid process contract
         * memberships which span zones, contract holders and processes
         * which aren't the sole members of their encapsulating process
         * contracts are not allowed to zone_enter.
         */
        ctp = pp->p_ct_process;
        ct = &ctp->conp_contract;
        mutex_enter(&ct->ct_lock);
        mutex_enter(&pp->p_lock);
        if ((avl_numnodes(&pp->p_ct_held) != 0) || (ctp->conp_nmembers != 1)) {
                mutex_exit(&pp->p_lock);
                mutex_exit(&ct->ct_lock);
                mutex_exit(&zonehash_lock);
                err = EINVAL;
                goto out;
        }

        /*
         * Moreover, we don't allow processes whose encapsulating
         * process contracts have inherited extrazonal contracts.
         * While it would be easier to eliminate all process contracts
         * with inherited contracts, we need to be able to give a
         * restarted init (or other zone-penetrating process) its
         * predecessor's contracts.
         */
        if (ctp->conp_ninherited != 0) {
                contract_t *next;
                for (next = list_head(&ctp->conp_inherited); next;
                    next = list_next(&ctp->conp_inherited, next)) {
                        if (contract_getzuniqid(next) != zone->zone_uniqid) {
                                mutex_exit(&pp->p_lock);
                                mutex_exit(&ct->ct_lock);
                                mutex_exit(&zonehash_lock);
                                err = EINVAL;
                                goto out;
                        }
                }
        }

        mutex_exit(&pp->p_lock);
        mutex_exit(&ct->ct_lock);

        status = zone_status_get(zone);
        if (status < ZONE_IS_READY || status >= ZONE_IS_SHUTTING_DOWN) {
                /*
                 * Can't join
                 */
                mutex_exit(&zonehash_lock);
                err = EINVAL;
                goto out;
        }

        /*
         * Make sure new priv set is within the permitted set for caller
         */
        if (!priv_issubset(zone->zone_privset, &CR_OPPRIV(CRED()))) {
                mutex_exit(&zonehash_lock);
                err = EPERM;
                goto out;
        }
        /*
         * We want to momentarily drop zonehash_lock while we optimistically
         * bind curproc to the pool it should be running in.  This is safe
         * since the zone can't disappear (we have a hold on it).
         */
        zone_hold(zone);
        mutex_exit(&zonehash_lock);

        /*
         * Grab pool_lock to keep the pools configuration from changing
         * and to stop ourselves from getting rebound to another pool
         * until we join the zone.
         */
        if (pool_lock_intr() != 0) {
                zone_rele(zone);
                err = EINTR;
                goto out;
        }
        ASSERT(secpolicy_pool(CRED()) == 0);
        /*
         * Bind ourselves to the pool currently associated with the zone.
         */
        oldpool = curproc->p_pool;
        newpool = zone_pool_get(zone);
        if (pool_state == POOL_ENABLED && newpool != oldpool &&
            (err = pool_do_bind(newpool, P_PID, P_MYID,
            POOL_BIND_ALL)) != 0) {
                pool_unlock();
                zone_rele(zone);
                goto out;
        }

        /*
         * Grab cpu_lock now; we'll need it later when we call
         * task_join().
         */
        mutex_enter(&cpu_lock);
        mutex_enter(&zonehash_lock);
        /*
         * Make sure the zone hasn't moved on since we dropped zonehash_lock.
         */
        if (zone_status_get(zone) >= ZONE_IS_SHUTTING_DOWN) {
                /*
                 * Can't join anymore.
                 */
                mutex_exit(&zonehash_lock);
                mutex_exit(&cpu_lock);
                if (pool_state == POOL_ENABLED &&
                    newpool != oldpool)
                        (void) pool_do_bind(oldpool, P_PID, P_MYID,
                            POOL_BIND_ALL);
                pool_unlock();
                zone_rele(zone);
                err = EINVAL;
                goto out;
        }

        /*
         * a_lock must be held while transfering locked memory and swap
         * reservation from the global zone to the non global zone because
         * asynchronous faults on the processes' address space can lock
         * memory and reserve swap via MCL_FUTURE and MAP_NORESERVE
         * segments respectively.
         */
        AS_LOCK_ENTER(pp->p_as, RW_WRITER);
        swap = as_swresv();
        mutex_enter(&pp->p_lock);
        zone_proj0 = zone->zone_zsched->p_task->tk_proj;
        /* verify that we do not exceed and task or lwp limits */
        mutex_enter(&zone->zone_nlwps_lock);
        /* add new lwps to zone and zone's proj0 */
        zone_proj0->kpj_nlwps += pp->p_lwpcnt;
        zone->zone_nlwps += pp->p_lwpcnt;
        /* add 1 task to zone's proj0 */
        zone_proj0->kpj_ntasks += 1;

        zone_proj0->kpj_nprocs++;
        zone->zone_nprocs++;
        mutex_exit(&zone->zone_nlwps_lock);

        mutex_enter(&zone->zone_mem_lock);
        zone->zone_locked_mem += pp->p_locked_mem;
        zone_proj0->kpj_data.kpd_locked_mem += pp->p_locked_mem;
        zone->zone_max_swap += swap;
        mutex_exit(&zone->zone_mem_lock);

        mutex_enter(&(zone_proj0->kpj_data.kpd_crypto_lock));
        zone_proj0->kpj_data.kpd_crypto_mem += pp->p_crypto_mem;
        mutex_exit(&(zone_proj0->kpj_data.kpd_crypto_lock));

        /* remove lwps and process from proc's old zone and old project */
        mutex_enter(&pp->p_zone->zone_nlwps_lock);
        pp->p_zone->zone_nlwps -= pp->p_lwpcnt;
        pp->p_task->tk_proj->kpj_nlwps -= pp->p_lwpcnt;
        pp->p_task->tk_proj->kpj_nprocs--;
        pp->p_zone->zone_nprocs--;
        mutex_exit(&pp->p_zone->zone_nlwps_lock);

        mutex_enter(&pp->p_zone->zone_mem_lock);
        pp->p_zone->zone_locked_mem -= pp->p_locked_mem;
        pp->p_task->tk_proj->kpj_data.kpd_locked_mem -= pp->p_locked_mem;
        pp->p_zone->zone_max_swap -= swap;
        mutex_exit(&pp->p_zone->zone_mem_lock);

        mutex_enter(&(pp->p_task->tk_proj->kpj_data.kpd_crypto_lock));
        pp->p_task->tk_proj->kpj_data.kpd_crypto_mem -= pp->p_crypto_mem;
        mutex_exit(&(pp->p_task->tk_proj->kpj_data.kpd_crypto_lock));

        pp->p_flag |= SZONETOP;
        pp->p_zone = zone;
        mutex_exit(&pp->p_lock);
        AS_LOCK_EXIT(pp->p_as);

        /*
         * Joining the zone cannot fail from now on.
         *
         * This means that a lot of the following code can be commonized and
         * shared with zsched().
         */

        /*
         * If the process contract fmri was inherited, we need to
         * flag this so that any contract status will not leak
         * extra zone information, svc_fmri in this case
         */
        if (ctp->conp_svc_ctid != ct->ct_id) {
                mutex_enter(&ct->ct_lock);
                ctp->conp_svc_zone_enter = ct->ct_id;
                mutex_exit(&ct->ct_lock);
        }

        /*
         * Reset the encapsulating process contract's zone.
         */
        ASSERT(ct->ct_mzuniqid == GLOBAL_ZONEUNIQID);
        contract_setzuniqid(ct, zone->zone_uniqid);

        /*
         * Create a new task and associate the process with the project keyed
         * by (projid,zoneid).
         *
         * We might as well be in project 0; the global zone's projid doesn't
         * make much sense in a zone anyhow.
         *
         * This also increments zone_ntasks, and returns with p_lock held.
         */
        tk = task_create(0, zone);
        oldtk = task_join(tk, 0);
        mutex_exit(&cpu_lock);

        /*
         * call RCTLOP_SET functions on this proc
         */
        e.rcep_p.zone = zone;
        e.rcep_t = RCENTITY_ZONE;
        (void) rctl_set_dup(NULL, NULL, pp, &e, zone->zone_rctls, NULL,
            RCD_CALLBACK);
        mutex_exit(&pp->p_lock);

        /*
         * We don't need to hold any of zsched's locks here; not only do we know
         * the process and zone aren't going away, we know its session isn't
         * changing either.
         *
         * By joining zsched's session here, we mimic the behavior in the
         * global zone of init's sid being the pid of sched.  We extend this
         * to all zlogin-like zone_enter()'ing processes as well.
         */
        mutex_enter(&pidlock);
        sp = zone->zone_zsched->p_sessp;
        sess_hold(zone->zone_zsched);
        mutex_enter(&pp->p_lock);
        pgexit(pp);
        sess_rele(pp->p_sessp, B_TRUE);
        pp->p_sessp = sp;
        pgjoin(pp, zone->zone_zsched->p_pidp);

        /*
         * If any threads are scheduled to be placed on zone wait queue they
         * should abandon the idea since the wait queue is changing.
         * We need to be holding pidlock & p_lock to do this.
         */
        if ((t = pp->p_tlist) != NULL) {
                do {
                        thread_lock(t);
                        /*
                         * Kick this thread so that it doesn't sit
                         * on a wrong wait queue.
                         */
                        if (ISWAITING(t))
                                setrun_locked(t);

                        if (t->t_schedflag & TS_ANYWAITQ)
                                t->t_schedflag &= ~ TS_ANYWAITQ;

                        thread_unlock(t);
                } while ((t = t->t_forw) != pp->p_tlist);
        }

        /*
         * If there is a default scheduling class for the zone and it is not
         * the class we are currently in, change all of the threads in the
         * process to the new class.  We need to be holding pidlock & p_lock
         * when we call parmsset so this is a good place to do it.
         */
        if (zone->zone_defaultcid > 0 &&
            zone->zone_defaultcid != curthread->t_cid) {
                pcparms_t pcparms;

                pcparms.pc_cid = zone->zone_defaultcid;
                pcparms.pc_clparms[0] = 0;

                /*
                 * If setting the class fails, we still want to enter the zone.
                 */
                if ((t = pp->p_tlist) != NULL) {
                        do {
                                (void) parmsset(&pcparms, t);
                        } while ((t = t->t_forw) != pp->p_tlist);
                }
        }

        mutex_exit(&pp->p_lock);
        mutex_exit(&pidlock);

        mutex_exit(&zonehash_lock);
        /*
         * We're firmly in the zone; let pools progress.
         */
        pool_unlock();
        task_rele(oldtk);
        /*
         * We don't need to retain a hold on the zone since we already
         * incremented zone_ntasks, so the zone isn't going anywhere.
         */
        zone_rele(zone);

        /*
         * Chroot
         */
        vp = zone->zone_rootvp;
        zone_chdir(vp, &PTOU(pp)->u_cdir, pp);
        zone_chdir(vp, &PTOU(pp)->u_rdir, pp);

        /*
         * Change process security flags.  Note that the _effective_ flags
         * cannot change
         */
        secflags_copy(&pp->p_secflags.psf_lower,
            &zone->zone_secflags.psf_lower);
        secflags_copy(&pp->p_secflags.psf_upper,
            &zone->zone_secflags.psf_upper);
        secflags_copy(&pp->p_secflags.psf_inherit,
            &zone->zone_secflags.psf_inherit);

        /*
         * Change process credentials
         */
        newcr = cralloc();
        mutex_enter(&pp->p_crlock);
        cr = pp->p_cred;
        crcopy_to(cr, newcr);
        crsetzone(newcr, zone);
        pp->p_cred = newcr;

        /*
         * Restrict all process privilege sets to zone limit
         */
        priv_intersect(zone->zone_privset, &CR_PPRIV(newcr));
        priv_intersect(zone->zone_privset, &CR_EPRIV(newcr));
        priv_intersect(zone->zone_privset, &CR_IPRIV(newcr));
        priv_intersect(zone->zone_privset, &CR_LPRIV(newcr));
        mutex_exit(&pp->p_crlock);
        crset(pp, newcr);

        /*
         * Adjust upcount to reflect zone entry.
         */
        uid = crgetruid(newcr);
        mutex_enter(&pidlock);
        upcount_dec(uid, GLOBAL_ZONEID);
        upcount_inc(uid, zoneid);
        mutex_exit(&pidlock);

        /*
         * Set up core file path and content.
         */
        set_core_defaults();

out:
        /*
         * Let the other lwps continue.
         */
        mutex_enter(&pp->p_lock);
        if (curthread != pp->p_agenttp)
                continuelwps(pp);
        mutex_exit(&pp->p_lock);

        return (err != 0 ? set_errno(err) : 0);
}

/*
 * Systemcall entry point for zone_list(2).
 *
 * Processes running in a (non-global) zone only see themselves.
 */
static int
zone_list(zoneid_t *zoneidlist, uint_t *numzones)
{
        zoneid_t *zoneids;
        zone_t *zone, *myzone;
        uint_t user_nzones, real_nzones;
        uint_t domi_nzones;
        int error;

        if (copyin(numzones, &user_nzones, sizeof (uint_t)) != 0)
                return (set_errno(EFAULT));

        myzone = curproc->p_zone;
        if (myzone != global_zone) {
                /* just return current zone */
                real_nzones = domi_nzones = 1;
                zoneids = kmem_alloc(sizeof (zoneid_t), KM_SLEEP);
                zoneids[0] = myzone->zone_id;
        } else {
                mutex_enter(&zonehash_lock);
                real_nzones = zonecount;
                domi_nzones = 0;
                if (real_nzones > 0) {
                        zoneids = kmem_alloc(real_nzones * sizeof (zoneid_t),
                            KM_SLEEP);
                        for (zone = list_head(&zone_active); zone != NULL;
                            zone = list_next(&zone_active, zone))
                                zoneids[domi_nzones++] = zone->zone_id;
                        ASSERT(domi_nzones == real_nzones);
                }
                mutex_exit(&zonehash_lock);
        }

        /*
         * If user has allocated space for fewer entries than we found, then
         * return only up to their limit.  Either way, tell them exactly how
         * many we found.
         */
        if (domi_nzones < user_nzones)
                user_nzones = domi_nzones;
        error = 0;
        if (copyout(&domi_nzones, numzones, sizeof (uint_t)) != 0) {
                error = EFAULT;
        } else if (zoneidlist != NULL && user_nzones != 0) {
                if (copyout(zoneids, zoneidlist,
                    user_nzones * sizeof (zoneid_t)) != 0)
                        error = EFAULT;
        }

        if (real_nzones > 0)
                kmem_free(zoneids, real_nzones * sizeof (zoneid_t));

        if (error != 0)
                return (set_errno(error));
        else
                return (0);
}

/*
 * Systemcall entry point for zone_lookup(2).
 *
 * Non-global zones are only able to see themselves.
 */
static zoneid_t
zone_lookup(const char *zone_name)
{
        char *kname;
        zone_t *zone;
        zoneid_t zoneid;
        int err;

        if (zone_name == NULL) {
                /* return caller's zone id */
                return (getzoneid());
        }

        kname = kmem_zalloc(ZONENAME_MAX, KM_SLEEP);
        if ((err = copyinstr(zone_name, kname, ZONENAME_MAX, NULL)) != 0) {
                kmem_free(kname, ZONENAME_MAX);
                return (set_errno(err));
        }

        mutex_enter(&zonehash_lock);
        zone = zone_find_all_by_name(kname);
        kmem_free(kname, ZONENAME_MAX);
        /* In a non-global zone, can only lookup global and own name. */
        if (zone == NULL ||
            zone_status_get(zone) < ZONE_IS_READY ||
            !zone_list_access(zone)) {
                mutex_exit(&zonehash_lock);
                return (set_errno(EINVAL));
        } else {
                zoneid = zone->zone_id;
                mutex_exit(&zonehash_lock);
                return (zoneid);
        }
}

static int
zone_version(int *version_arg)
{
        int version = ZONE_SYSCALL_API_VERSION;

        if (copyout(&version, version_arg, sizeof (int)) != 0)
                return (set_errno(EFAULT));
        return (0);
}

/* ARGSUSED */
long
zone(int cmd, void *arg1, void *arg2, void *arg3, void *arg4)
{
        zone_def zs;
        int err;

        switch (cmd) {
        case ZONE_CREATE:
                if (get_udatamodel() == DATAMODEL_NATIVE) {
                        if (copyin(arg1, &zs, sizeof (zone_def))) {
                                return (set_errno(EFAULT));
                        }
                } else {
#ifdef _SYSCALL32_IMPL
                        zone_def32 zs32;

                        if (copyin(arg1, &zs32, sizeof (zone_def32))) {
                                return (set_errno(EFAULT));
                        }
                        zs.zone_name =
                            (const char *)(unsigned long)zs32.zone_name;
                        zs.zone_root =
                            (const char *)(unsigned long)zs32.zone_root;
                        zs.zone_privs =
                            (const struct priv_set *)
                            (unsigned long)zs32.zone_privs;
                        zs.zone_privssz = zs32.zone_privssz;
                        zs.rctlbuf = (caddr_t)(unsigned long)zs32.rctlbuf;
                        zs.rctlbufsz = zs32.rctlbufsz;
                        zs.zfsbuf = (caddr_t)(unsigned long)zs32.zfsbuf;
                        zs.zfsbufsz = zs32.zfsbufsz;
                        zs.extended_error =
                            (int *)(unsigned long)zs32.extended_error;
                        zs.flags = zs32.flags;
#else
                        panic("get_udatamodel() returned bogus result\n");
#endif
                }

                return (zone_create(zs.zone_name, zs.zone_root,
                    zs.zone_privs, zs.zone_privssz,
                    (caddr_t)zs.rctlbuf, zs.rctlbufsz,
                    (caddr_t)zs.zfsbuf, zs.zfsbufsz,
                    zs.extended_error, zs.flags));
        case ZONE_BOOT:
                return (zone_boot((zoneid_t)(uintptr_t)arg1));
        case ZONE_DESTROY:
                return (zone_destroy((zoneid_t)(uintptr_t)arg1));
        case ZONE_GETATTR:
                return (zone_getattr((zoneid_t)(uintptr_t)arg1,
                    (int)(uintptr_t)arg2, arg3, (size_t)arg4));
        case ZONE_SETATTR:
                return (zone_setattr((zoneid_t)(uintptr_t)arg1,
                    (int)(uintptr_t)arg2, arg3, (size_t)arg4));
        case ZONE_ENTER:
                return (zone_enter((zoneid_t)(uintptr_t)arg1));
        case ZONE_LIST:
                return (zone_list((zoneid_t *)arg1, (uint_t *)arg2));
        case ZONE_SHUTDOWN:
                return (zone_shutdown((zoneid_t)(uintptr_t)arg1));
        case ZONE_LOOKUP:
                return (zone_lookup((const char *)arg1));
        case ZONE_VERSION:
                return (zone_version((int *)arg1));
        case ZONE_ADD_DATALINK:
                return (zone_add_datalink((zoneid_t)(uintptr_t)arg1,
                    (datalink_id_t)(uintptr_t)arg2));
        case ZONE_DEL_DATALINK:
                return (zone_remove_datalink((zoneid_t)(uintptr_t)arg1,
                    (datalink_id_t)(uintptr_t)arg2));
        case ZONE_CHECK_DATALINK: {
                zoneid_t        zoneid;
                boolean_t       need_copyout;

                if (copyin(arg1, &zoneid, sizeof (zoneid)) != 0)
                        return (EFAULT);
                need_copyout = (zoneid == ALL_ZONES);
                err = zone_check_datalink(&zoneid,
                    (datalink_id_t)(uintptr_t)arg2);
                if (err == 0 && need_copyout) {
                        if (copyout(&zoneid, arg1, sizeof (zoneid)) != 0)
                                err = EFAULT;
                }
                return (err == 0 ? 0 : set_errno(err));
        }
        case ZONE_LIST_DATALINK:
                return (zone_list_datalink((zoneid_t)(uintptr_t)arg1,
                    (int *)arg2, (datalink_id_t *)(uintptr_t)arg3));
        default:
                return (set_errno(EINVAL));
        }
}

struct zarg {
        zone_t *zone;
        zone_cmd_arg_t arg;
};

static int
zone_lookup_door(const char *zone_name, door_handle_t *doorp)
{
        char *buf;
        size_t buflen;
        int error;

        buflen = sizeof (ZONE_DOOR_PATH) + strlen(zone_name);
        buf = kmem_alloc(buflen, KM_SLEEP);
        (void) snprintf(buf, buflen, ZONE_DOOR_PATH, zone_name);
        error = door_ki_open(buf, doorp);
        kmem_free(buf, buflen);
        return (error);
}

static void
zone_release_door(door_handle_t *doorp)
{
        door_ki_rele(*doorp);
        *doorp = NULL;
}

static void
zone_ki_call_zoneadmd(struct zarg *zargp)
{
        door_handle_t door = NULL;
        door_arg_t darg, save_arg;
        char *zone_name;
        size_t zone_namelen;
        zoneid_t zoneid;
        zone_t *zone;
        zone_cmd_arg_t arg;
        uint64_t uniqid;
        size_t size;
        int error;
        int retry;

        zone = zargp->zone;
        arg = zargp->arg;
        kmem_free(zargp, sizeof (*zargp));

        zone_namelen = strlen(zone->zone_name) + 1;
        zone_name = kmem_alloc(zone_namelen, KM_SLEEP);
        bcopy(zone->zone_name, zone_name, zone_namelen);
        zoneid = zone->zone_id;
        uniqid = zone->zone_uniqid;
        /*
         * zoneadmd may be down, but at least we can empty out the zone.
         * We can ignore the return value of zone_empty() since we're called
         * from a kernel thread and know we won't be delivered any signals.
         */
        ASSERT(curproc == &p0);
        (void) zone_empty(zone);
        ASSERT(zone_status_get(zone) >= ZONE_IS_EMPTY);
        zone_rele(zone);

        size = sizeof (arg);
        darg.rbuf = (char *)&arg;
        darg.data_ptr = (char *)&arg;
        darg.rsize = size;
        darg.data_size = size;
        darg.desc_ptr = NULL;
        darg.desc_num = 0;

        save_arg = darg;
        /*
         * Since we're not holding a reference to the zone, any number of
         * things can go wrong, including the zone disappearing before we get a
         * chance to talk to zoneadmd.
         */
        for (retry = 0; /* forever */; retry++) {
                if (door == NULL &&
                    (error = zone_lookup_door(zone_name, &door)) != 0) {
                        goto next;
                }
                ASSERT(door != NULL);

                if ((error = door_ki_upcall_limited(door, &darg, NULL,
                    SIZE_MAX, 0)) == 0) {
                        break;
                }
                switch (error) {
                case EINTR:
                        /* FALLTHROUGH */
                case EAGAIN:    /* process may be forking */
                        /*
                         * Back off for a bit
                         */
                        break;
                case EBADF:
                        zone_release_door(&door);
                        if (zone_lookup_door(zone_name, &door) != 0) {
                                /*
                                 * zoneadmd may be dead, but it may come back to
                                 * life later.
                                 */
                                break;
                        }
                        break;
                default:
                        cmn_err(CE_WARN,
                            "zone_ki_call_zoneadmd: door_ki_upcall error %d\n",
                            error);
                        goto out;
                }
next:
                /*
                 * If this isn't the same zone_t that we originally had in mind,
                 * then this is the same as if two kadmin requests come in at
                 * the same time: the first one wins.  This means we lose, so we
                 * bail.
                 */
                if ((zone = zone_find_by_id(zoneid)) == NULL) {
                        /*
                         * Problem is solved.
                         */
                        break;
                }
                if (zone->zone_uniqid != uniqid) {
                        /*
                         * zoneid recycled
                         */
                        zone_rele(zone);
                        break;
                }
                /*
                 * We could zone_status_timedwait(), but there doesn't seem to
                 * be much point in doing that (plus, it would mean that
                 * zone_free() isn't called until this thread exits).
                 */
                zone_rele(zone);
                ddi_sleep(1);
                darg = save_arg;
        }
out:
        if (door != NULL) {
                zone_release_door(&door);
        }
        kmem_free(zone_name, zone_namelen);
        thread_exit();
}

/*
 * Entry point for uadmin() to tell the zone to go away or reboot.  Analog to
 * kadmin().  The caller is a process in the zone.
 *
 * In order to shutdown the zone, we will hand off control to zoneadmd
 * (running in the global zone) via a door.  We do a half-hearted job at
 * killing all processes in the zone, create a kernel thread to contact
 * zoneadmd, and make note of the "uniqid" of the zone.  The uniqid is
 * a form of generation number used to let zoneadmd (as well as
 * zone_destroy()) know exactly which zone they're re talking about.
 */
int
zone_kadmin(int cmd, int fcn, const char *mdep, cred_t *credp)
{
        struct zarg *zargp;
        zone_cmd_t zcmd;
        zone_t *zone;

        zone = curproc->p_zone;
        ASSERT(getzoneid() != GLOBAL_ZONEID);

        switch (cmd) {
        case A_SHUTDOWN:
                switch (fcn) {
                case AD_HALT:
                case AD_POWEROFF:
                        zcmd = Z_HALT;
                        break;
                case AD_BOOT:
                        zcmd = Z_REBOOT;
                        break;
                case AD_IBOOT:
                case AD_SBOOT:
                case AD_SIBOOT:
                case AD_NOSYNC:
                        return (ENOTSUP);
                default:
                        return (EINVAL);
                }
                break;
        case A_REBOOT:
                zcmd = Z_REBOOT;
                break;
        case A_FTRACE:
        case A_REMOUNT:
        case A_FREEZE:
        case A_DUMP:
        case A_CONFIG:
                return (ENOTSUP);
        default:
                ASSERT(cmd != A_SWAPCTL);       /* handled by uadmin() */
                return (EINVAL);
        }

        if (secpolicy_zone_admin(credp, B_FALSE))
                return (EPERM);
        mutex_enter(&zone_status_lock);

        /*
         * zone_status can't be ZONE_IS_EMPTY or higher since curproc
         * is in the zone.
         */
        ASSERT(zone_status_get(zone) < ZONE_IS_EMPTY);
        if (zone_status_get(zone) > ZONE_IS_RUNNING) {
                /*
                 * This zone is already on its way down.
                 */
                mutex_exit(&zone_status_lock);
                return (0);
        }
        /*
         * Prevent future zone_enter()s
         */
        zone_status_set(zone, ZONE_IS_SHUTTING_DOWN);
        mutex_exit(&zone_status_lock);

        /*
         * Kill everyone now and call zoneadmd later.
         * zone_ki_call_zoneadmd() will do a more thorough job of this
         * later.
         */
        killall(zone->zone_id);
        /*
         * Now, create the thread to contact zoneadmd and do the rest of the
         * work.  This thread can't be created in our zone otherwise
         * zone_destroy() would deadlock.
         */
        zargp = kmem_zalloc(sizeof (*zargp), KM_SLEEP);
        zargp->arg.cmd = zcmd;
        zargp->arg.uniqid = zone->zone_uniqid;
        zargp->zone = zone;
        (void) strcpy(zargp->arg.locale, "C");
        /* mdep was already copied in for us by uadmin */
        if (mdep != NULL)
                (void) strlcpy(zargp->arg.bootbuf, mdep,
                    sizeof (zargp->arg.bootbuf));
        zone_hold(zone);

        (void) thread_create(NULL, 0, zone_ki_call_zoneadmd, zargp, 0, &p0,
            TS_RUN, minclsyspri);
        exit(CLD_EXITED, 0);

        return (EINVAL);
}

/*
 * Entry point so kadmin(A_SHUTDOWN, ...) can set the global zone's
 * status to ZONE_IS_SHUTTING_DOWN.
 *
 * This function also shuts down all running zones to ensure that they won't
 * fork new processes.
 */
void
zone_shutdown_global(void)
{
        zone_t *current_zonep;

        ASSERT(INGLOBALZONE(curproc));
        mutex_enter(&zonehash_lock);
        mutex_enter(&zone_status_lock);

        /* Modify the global zone's status first. */
        ASSERT(zone_status_get(global_zone) == ZONE_IS_RUNNING);
        zone_status_set(global_zone, ZONE_IS_SHUTTING_DOWN);

        /*
         * Now change the states of all running zones to ZONE_IS_SHUTTING_DOWN.
         * We don't mark all zones with ZONE_IS_SHUTTING_DOWN because doing so
         * could cause assertions to fail (e.g., assertions about a zone's
         * state during initialization, readying, or booting) or produce races.
         * We'll let threads continue to initialize and ready new zones: they'll
         * fail to boot the new zones when they see that the global zone is
         * shutting down.
         */
        for (current_zonep = list_head(&zone_active); current_zonep != NULL;
            current_zonep = list_next(&zone_active, current_zonep)) {
                if (zone_status_get(current_zonep) == ZONE_IS_RUNNING)
                        zone_status_set(current_zonep, ZONE_IS_SHUTTING_DOWN);
        }
        mutex_exit(&zone_status_lock);
        mutex_exit(&zonehash_lock);
}

/*
 * Returns true if the named dataset is visible in the current zone.
 * The 'write' parameter is set to 1 if the dataset is also writable.
 */
int
zone_dataset_visible(const char *dataset, int *write)
{
        static int zfstype = -1;
        zone_dataset_t *zd;
        size_t len;
        zone_t *zone = curproc->p_zone;
        const char *name = NULL;
        vfs_t *vfsp = NULL;

        if (dataset[0] == '\0')
                return (0);

        /*
         * Walk the list once, looking for datasets which match exactly, or
         * specify a dataset underneath an exported dataset.  If found, return
         * true and note that it is writable.
         */
        for (zd = list_head(&zone->zone_datasets); zd != NULL;
            zd = list_next(&zone->zone_datasets, zd)) {

                len = strlen(zd->zd_dataset);
                if (strlen(dataset) >= len &&
                    bcmp(dataset, zd->zd_dataset, len) == 0 &&
                    (dataset[len] == '\0' || dataset[len] == '/' ||
                    dataset[len] == '@')) {
                        if (write)
                                *write = 1;
                        return (1);
                }
        }

        /*
         * Walk the list a second time, searching for datasets which are parents
         * of exported datasets.  These should be visible, but read-only.
         *
         * Note that we also have to support forms such as 'pool/dataset/', with
         * a trailing slash.
         */
        for (zd = list_head(&zone->zone_datasets); zd != NULL;
            zd = list_next(&zone->zone_datasets, zd)) {

                len = strlen(dataset);
                if (dataset[len - 1] == '/')
                        len--;  /* Ignore trailing slash */
                if (len < strlen(zd->zd_dataset) &&
                    bcmp(dataset, zd->zd_dataset, len) == 0 &&
                    zd->zd_dataset[len] == '/') {
                        if (write)
                                *write = 0;
                        return (1);
                }
        }

        /*
         * We reach here if the given dataset is not found in the zone_dataset
         * list. Check if this dataset was added as a filesystem (ie. "add fs")
         * instead of delegation. For this we search for the dataset in the
         * zone_vfslist of this zone. If found, return true and note that it is
         * not writable.
         */

        /*
         * Initialize zfstype if it is not initialized yet.
         */
        if (zfstype == -1) {
                struct vfssw *vswp = vfs_getvfssw("zfs");
                zfstype = vswp - vfssw;
                vfs_unrefvfssw(vswp);
        }

        vfs_list_read_lock();
        vfsp = zone->zone_vfslist;
        do {
                ASSERT(vfsp);
                if (vfsp->vfs_fstype == zfstype) {
                        name = refstr_value(vfsp->vfs_resource);

                        /*
                         * Check if we have an exact match.
                         */
                        if (strcmp(dataset, name) == 0) {
                                vfs_list_unlock();
                                if (write)
                                        *write = 0;
                                return (1);
                        }
                        /*
                         * We need to check if we are looking for parents of
                         * a dataset. These should be visible, but read-only.
                         */
                        len = strlen(dataset);
                        if (dataset[len - 1] == '/')
                                len--;

                        if (len < strlen(name) &&
                            bcmp(dataset, name, len) == 0 && name[len] == '/') {
                                vfs_list_unlock();
                                if (write)
                                        *write = 0;
                                return (1);
                        }
                }
                vfsp = vfsp->vfs_zone_next;
        } while (vfsp != zone->zone_vfslist);

        vfs_list_unlock();
        return (0);
}

/*
 * zone_find_by_any_path() -
 *
 * kernel-private routine similar to zone_find_by_path(), but which
 * effectively compares against zone paths rather than zonerootpath
 * (i.e., the last component of zonerootpaths, which should be "root/",
 * are not compared.)  This is done in order to accurately identify all
 * paths, whether zone-visible or not, including those which are parallel
 * to /root/, such as /dev/, /home/, etc...
 *
 * If the specified path does not fall under any zone path then global
 * zone is returned.
 *
 * The treat_abs parameter indicates whether the path should be treated as
 * an absolute path although it does not begin with "/".  (This supports
 * nfs mount syntax such as host:any/path.)
 *
 * The caller is responsible for zone_rele of the returned zone.
 */
zone_t *
zone_find_by_any_path(const char *path, boolean_t treat_abs)
{
        zone_t *zone;
        int path_offset = 0;

        if (path == NULL) {
                zone_hold(global_zone);
                return (global_zone);
        }

        if (*path != '/') {
                ASSERT(treat_abs);
                path_offset = 1;
        }

        mutex_enter(&zonehash_lock);
        for (zone = list_head(&zone_active); zone != NULL;
            zone = list_next(&zone_active, zone)) {
                char    *c;
                size_t  pathlen;
                char *rootpath_start;

                if (zone == global_zone)        /* skip global zone */
                        continue;

                /* scan backwards to find start of last component */
                c = zone->zone_rootpath + zone->zone_rootpathlen - 2;
                do {
                        c--;
                } while (*c != '/');

                pathlen = c - zone->zone_rootpath + 1 - path_offset;
                rootpath_start = (zone->zone_rootpath + path_offset);
                if (strncmp(path, rootpath_start, pathlen) == 0)
                        break;
        }
        if (zone == NULL)
                zone = global_zone;
        zone_hold(zone);
        mutex_exit(&zonehash_lock);
        return (zone);
}

/*
 * Finds a zone_dl_t with the given linkid in the given zone.  Returns the
 * zone_dl_t pointer if found, and NULL otherwise.
 */
static zone_dl_t *
zone_find_dl(zone_t *zone, datalink_id_t linkid)
{
        zone_dl_t *zdl;

        ASSERT(mutex_owned(&zone->zone_lock));
        for (zdl = list_head(&zone->zone_dl_list); zdl != NULL;
            zdl = list_next(&zone->zone_dl_list, zdl)) {
                if (zdl->zdl_id == linkid)
                        break;
        }
        return (zdl);
}

static boolean_t
zone_dl_exists(zone_t *zone, datalink_id_t linkid)
{
        boolean_t exists;

        mutex_enter(&zone->zone_lock);
        exists = (zone_find_dl(zone, linkid) != NULL);
        mutex_exit(&zone->zone_lock);
        return (exists);
}

/*
 * Add an data link name for the zone.
 */
static int
zone_add_datalink(zoneid_t zoneid, datalink_id_t linkid)
{
        zone_dl_t *zdl;
        zone_t *zone;
        zone_t *thiszone;

        if ((thiszone = zone_find_by_id(zoneid)) == NULL)
                return (set_errno(ENXIO));

        /* Verify that the datalink ID doesn't already belong to a zone. */
        mutex_enter(&zonehash_lock);
        for (zone = list_head(&zone_active); zone != NULL;
            zone = list_next(&zone_active, zone)) {
                if (zone_dl_exists(zone, linkid)) {
                        mutex_exit(&zonehash_lock);
                        zone_rele(thiszone);
                        return (set_errno((zone == thiszone) ? EEXIST : EPERM));
                }
        }

        zdl = kmem_zalloc(sizeof (*zdl), KM_SLEEP);
        zdl->zdl_id = linkid;
        zdl->zdl_net = NULL;
        mutex_enter(&thiszone->zone_lock);
        list_insert_head(&thiszone->zone_dl_list, zdl);
        mutex_exit(&thiszone->zone_lock);
        mutex_exit(&zonehash_lock);
        zone_rele(thiszone);
        return (0);
}

static int
zone_remove_datalink(zoneid_t zoneid, datalink_id_t linkid)
{
        zone_dl_t *zdl;
        zone_t *zone;
        int err = 0;

        if ((zone = zone_find_by_id(zoneid)) == NULL)
                return (set_errno(EINVAL));

        mutex_enter(&zone->zone_lock);
        if ((zdl = zone_find_dl(zone, linkid)) == NULL) {
                err = ENXIO;
        } else {
                list_remove(&zone->zone_dl_list, zdl);
                nvlist_free(zdl->zdl_net);
                kmem_free(zdl, sizeof (zone_dl_t));
        }
        mutex_exit(&zone->zone_lock);
        zone_rele(zone);
        return (err == 0 ? 0 : set_errno(err));
}

/*
 * Using the zoneidp as ALL_ZONES, we can lookup which zone has been assigned
 * the linkid.  Otherwise we just check if the specified zoneidp has been
 * assigned the supplied linkid.
 */
int
zone_check_datalink(zoneid_t *zoneidp, datalink_id_t linkid)
{
        zone_t *zone;
        int err = ENXIO;

        if (*zoneidp != ALL_ZONES) {
                if ((zone = zone_find_by_id(*zoneidp)) != NULL) {
                        if (zone_dl_exists(zone, linkid))
                                err = 0;
                        zone_rele(zone);
                }
                return (err);
        }

        mutex_enter(&zonehash_lock);
        for (zone = list_head(&zone_active); zone != NULL;
            zone = list_next(&zone_active, zone)) {
                if (zone_dl_exists(zone, linkid)) {
                        *zoneidp = zone->zone_id;
                        err = 0;
                        break;
                }
        }
        mutex_exit(&zonehash_lock);
        return (err);
}

/*
 * Get the list of datalink IDs assigned to a zone.
 *
 * On input, *nump is the number of datalink IDs that can fit in the supplied
 * idarray.  Upon return, *nump is either set to the number of datalink IDs
 * that were placed in the array if the array was large enough, or to the
 * number of datalink IDs that the function needs to place in the array if the
 * array is too small.
 */
static int
zone_list_datalink(zoneid_t zoneid, int *nump, datalink_id_t *idarray)
{
        uint_t num, dlcount;
        zone_t *zone;
        zone_dl_t *zdl;
        datalink_id_t *idptr = idarray;

        if (copyin(nump, &dlcount, sizeof (dlcount)) != 0)
                return (set_errno(EFAULT));
        if ((zone = zone_find_by_id(zoneid)) == NULL)
                return (set_errno(ENXIO));

        num = 0;
        mutex_enter(&zone->zone_lock);
        for (zdl = list_head(&zone->zone_dl_list); zdl != NULL;
            zdl = list_next(&zone->zone_dl_list, zdl)) {
                /*
                 * If the list is bigger than what the caller supplied, just
                 * count, don't do copyout.
                 */
                if (++num > dlcount)
                        continue;
                if (copyout(&zdl->zdl_id, idptr, sizeof (*idptr)) != 0) {
                        mutex_exit(&zone->zone_lock);
                        zone_rele(zone);
                        return (set_errno(EFAULT));
                }
                idptr++;
        }
        mutex_exit(&zone->zone_lock);
        zone_rele(zone);

        /* Increased or decreased, caller should be notified. */
        if (num != dlcount) {
                if (copyout(&num, nump, sizeof (num)) != 0)
                        return (set_errno(EFAULT));
        }
        return (0);
}

/*
 * Public interface for looking up a zone by zoneid. It's a customized version
 * for netstack_zone_create(). It can only be called from the zsd create
 * callbacks, since it doesn't have reference on the zone structure hence if
 * it is called elsewhere the zone could disappear after the zonehash_lock
 * is dropped.
 *
 * Furthermore it
 * 1. Doesn't check the status of the zone.
 * 2. It will be called even before zone_init is called, in that case the
 *    address of zone0 is returned directly, and netstack_zone_create()
 *    will only assign a value to zone0.zone_netstack, won't break anything.
 * 3. Returns without the zone being held.
 */
zone_t *
zone_find_by_id_nolock(zoneid_t zoneid)
{
        zone_t *zone;

        mutex_enter(&zonehash_lock);
        if (zonehashbyid == NULL)
                zone = &zone0;
        else
                zone = zone_find_all_by_id(zoneid);
        mutex_exit(&zonehash_lock);
        return (zone);
}

/*
 * Walk the datalinks for a given zone
 */
int
zone_datalink_walk(zoneid_t zoneid, int (*cb)(datalink_id_t, void *),
    void *data)
{
        zone_t          *zone;
        zone_dl_t       *zdl;
        datalink_id_t   *idarray;
        uint_t          idcount = 0;
        int             i, ret = 0;

        if ((zone = zone_find_by_id(zoneid)) == NULL)
                return (ENOENT);

        /*
         * We first build an array of linkid's so that we can walk these and
         * execute the callback with the zone_lock dropped.
         */
        mutex_enter(&zone->zone_lock);
        for (zdl = list_head(&zone->zone_dl_list); zdl != NULL;
            zdl = list_next(&zone->zone_dl_list, zdl)) {
                idcount++;
        }

        if (idcount == 0) {
                mutex_exit(&zone->zone_lock);
                zone_rele(zone);
                return (0);
        }

        idarray = kmem_alloc(sizeof (datalink_id_t) * idcount, KM_NOSLEEP);
        if (idarray == NULL) {
                mutex_exit(&zone->zone_lock);
                zone_rele(zone);
                return (ENOMEM);
        }

        for (i = 0, zdl = list_head(&zone->zone_dl_list); zdl != NULL;
            i++, zdl = list_next(&zone->zone_dl_list, zdl)) {
                idarray[i] = zdl->zdl_id;
        }

        mutex_exit(&zone->zone_lock);

        for (i = 0; i < idcount && ret == 0; i++) {
                if ((ret = (*cb)(idarray[i], data)) != 0)
                        break;
        }

        zone_rele(zone);
        kmem_free(idarray, sizeof (datalink_id_t) * idcount);
        return (ret);
}

static char *
zone_net_type2name(int type)
{
        switch (type) {
        case ZONE_NETWORK_ADDRESS:
                return (ZONE_NET_ADDRNAME);
        case ZONE_NETWORK_DEFROUTER:
                return (ZONE_NET_RTRNAME);
        default:
                return (NULL);
        }
}

static int
zone_set_network(zoneid_t zoneid, zone_net_data_t *znbuf)
{
        zone_t *zone;
        zone_dl_t *zdl;
        nvlist_t *nvl;
        int err = 0;
        uint8_t *new = NULL;
        char *nvname;
        int bufsize;
        datalink_id_t linkid = znbuf->zn_linkid;

        if (secpolicy_zone_config(CRED()) != 0)
                return (set_errno(EPERM));

        if (zoneid == GLOBAL_ZONEID)
                return (set_errno(EINVAL));

        nvname = zone_net_type2name(znbuf->zn_type);
        bufsize = znbuf->zn_len;
        new = znbuf->zn_val;
        if (nvname == NULL)
                return (set_errno(EINVAL));

        if ((zone = zone_find_by_id(zoneid)) == NULL) {
                return (set_errno(EINVAL));
        }

        mutex_enter(&zone->zone_lock);
        if ((zdl = zone_find_dl(zone, linkid)) == NULL) {
                err = ENXIO;
                goto done;
        }
        if ((nvl = zdl->zdl_net) == NULL) {
                if (nvlist_alloc(&nvl, NV_UNIQUE_NAME, KM_SLEEP)) {
                        err = ENOMEM;
                        goto done;
                } else {
                        zdl->zdl_net = nvl;
                }
        }
        if (nvlist_exists(nvl, nvname)) {
                err = EINVAL;
                goto done;
        }
        err = nvlist_add_uint8_array(nvl, nvname, new, bufsize);
        ASSERT(err == 0);
done:
        mutex_exit(&zone->zone_lock);
        zone_rele(zone);
        if (err != 0)
                return (set_errno(err));
        else
                return (0);
}

static int
zone_get_network(zoneid_t zoneid, zone_net_data_t *znbuf)
{
        zone_t *zone;
        zone_dl_t *zdl;
        nvlist_t *nvl;
        uint8_t *ptr;
        uint_t psize;
        int err = 0;
        char *nvname;
        int bufsize;
        void *buf;
        datalink_id_t linkid = znbuf->zn_linkid;

        if (zoneid == GLOBAL_ZONEID)
                return (set_errno(EINVAL));

        nvname = zone_net_type2name(znbuf->zn_type);
        bufsize = znbuf->zn_len;
        buf = znbuf->zn_val;

        if (nvname == NULL)
                return (set_errno(EINVAL));
        if ((zone = zone_find_by_id(zoneid)) == NULL)
                return (set_errno(EINVAL));

        mutex_enter(&zone->zone_lock);
        if ((zdl = zone_find_dl(zone, linkid)) == NULL) {
                err = ENXIO;
                goto done;
        }
        if ((nvl = zdl->zdl_net) == NULL || !nvlist_exists(nvl, nvname)) {
                err = ENOENT;
                goto done;
        }
        err = nvlist_lookup_uint8_array(nvl, nvname, &ptr, &psize);
        ASSERT(err == 0);

        if (psize > bufsize) {
                err = ENOBUFS;
                goto done;
        }
        znbuf->zn_len = psize;
        bcopy(ptr, buf, psize);
done:
        mutex_exit(&zone->zone_lock);
        zone_rele(zone);
        if (err != 0)
                return (set_errno(err));
        else
                return (0);
}