NEX-15279 support NFS server in zone
NEX-15520 online NFS shares cause zoneadm halt to hang in nfs_export_zone_fini
Portions contributed by: Dan Kruchinin dan.kruchinin@nexenta.com
Portions contributed by: Stepan Zastupov stepan.zastupov@gmail.com
Reviewed by: Joyce McIntosh <joyce.mcintosh@nexenta.com>
Reviewed by: Rob Gittins <rob.gittins@nexenta.com>
Reviewed by: Gordon Ross <gordon.ross@nexenta.com>

*** 22,36 ****
  /*
   * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
   * Use is subject to license terms.
   */
  
  #ifndef _SHAREFS_SHAREFS_H
  #define _SHAREFS_SHAREFS_H
  
- #pragma ident   "%Z%%M% %I%     %E% SMI"
- 
  /*
   * This header provides service for the sharefs module.
   */
  
  #include <sys/modctl.h>
--- 22,38 ----
  /*
   * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
   * Use is subject to license terms.
   */
  
+ /*
+  * Copyright 2018 Nexenta Systems, Inc.
+  */
+ 
  #ifndef _SHAREFS_SHAREFS_H
  #define _SHAREFS_SHAREFS_H
  
  /*
   * This header provides service for the sharefs module.
   */
  
  #include <sys/modctl.h>
*** 65,92 ****
          vnode_t *sharefs_vfs_root;
  } sharefs_vfs_t;
  
  #define SHAREFS_NAME_MAX        MAXNAMELEN
  
! /*
   * The lock ordering whenever sharefs_lock and sharetab_lock both
   * need to be held is: sharefs_lock and then sharetab_lock.
   */
! extern krwlock_t        sharefs_lock;   /* lock for the vnode ops */
! extern sharetab_t       *sharefs_sharetab;      /* The sharetab. */
  
! extern uint_t           sharetab_count; /* How many shares? */
! extern krwlock_t        sharetab_lock;  /* lock for the cached sharetab */
! extern size_t           sharetab_size;  /* How big is the sharetab file? */
  
! extern timestruc_t      sharetab_mtime; /* Last mod to sharetab */
! extern timestruc_t      sharetab_snap_time;     /* Last snap */
! extern uint_t           sharetab_generation;    /* Which copy is it? */
  
  #define SHAREFS_INO_FILE        0x80
  
  extern vnode_t *sharefs_create_root_file(vfs_t *);
  
  /*
   * Sharetab file
   *
   * Note that even though the sharetab code does not explictly
--- 67,97 ----
          vnode_t *sharefs_vfs_root;
  } sharefs_vfs_t;
  
  #define SHAREFS_NAME_MAX        MAXNAMELEN
  
! typedef struct sharetab_globals {
!         /*
           * The lock ordering whenever sharefs_lock and sharetab_lock both
           * need to be held is: sharefs_lock and then sharetab_lock.
           */
!         krwlock_t       sharefs_lock;   /* lock for the vnode ops */
!         sharetab_t      *sharefs_sharetab;      /* The sharetab. */
  
!         uint_t          sharetab_count; /* How many shares? */
!         krwlock_t       sharetab_lock;  /* lock for the cached sharetab */
!         size_t          sharetab_size;  /* How big is the sharetab file? */
  
!         timestruc_t     sharetab_mtime; /* Last mod to sharetab */
!         timestruc_t     sharetab_snap_time;     /* Last snap */
!         uint_t          sharetab_generation;    /* Which copy is it? */
! } sharetab_globals_t;
  
  #define SHAREFS_INO_FILE        0x80
  
  extern vnode_t *sharefs_create_root_file(vfs_t *);
+ extern sharetab_globals_t *sharetab_get_globals(zone_t *zone);
  
  /*
   * Sharetab file
   *
   * Note that even though the sharetab code does not explictly