7378 exported_lock held during nfs4 compound processing

*** 1920,1934 ****
                          if (error == ENOSPC)
                                  error = EREMOTE;
                          break;
                  }
  
!                 if (v4srv)
!                         exi = checkexport4(&vp->v_vfsp->vfs_fsid, &fid, vp);
!                 else
!                         exi = checkexport(&vp->v_vfsp->vfs_fsid, &fid);
! 
                  if (exi != NULL) {
                          /*
                           * Found the export info
                           */
                          break;
--- 1920,1931 ----
                          if (error == ENOSPC)
                                  error = EREMOTE;
                          break;
                  }
  
!                 exi = checkexport(&vp->v_vfsp->vfs_fsid, &fid,
!                     v4srv ? vp : NULL);
                  if (exi != NULL) {
                          /*
                           * Found the export info
                           */
                          break;
*** 2429,2448 ****
                  vp->v_type = VDIR;
          *statp = NFS4_OK;
          return (vp);
  }
  
- /*
-  * Find the export structure associated with the given filesystem.
-  * If found, then increment the ref count (exi_count).
-  */
  struct exportinfo *
! checkexport(fsid_t *fsid, fid_t *fid)
  {
          struct exportinfo *exi;
  
-         rw_enter(&exported_lock, RW_READER);
          for (exi = exptable[exptablehash(fsid, fid)];
              exi != NULL;
              exi = exi->fid_hash.next) {
                  if (exportmatch(exi, fsid, fid)) {
                          /*
--- 2426,2440 ----
                  vp->v_type = VDIR;
          *statp = NFS4_OK;
          return (vp);
  }
  
  struct exportinfo *
! checkexport_nohold(fsid_t *fsid, fid_t *fid, vnode_t *vp)
  {
          struct exportinfo *exi;
  
          for (exi = exptable[exptablehash(fsid, fid)];
              exi != NULL;
              exi = exi->fid_hash.next) {
                  if (exportmatch(exi, fsid, fid)) {
                          /*
*** 2453,2515 ****
                           */
                          if (exi->exi_export.ex_flags & EX_PUBLIC) {
                                  exi = exi_public;
                          }
  
!                         exi_hold(exi);
!                         rw_exit(&exported_lock);
                          return (exi);
                  }
          }
!         rw_exit(&exported_lock);
          return (NULL);
  }
  
- 
  /*
!  * "old school" version of checkexport() for NFS4.  NFS4
!  * rfs4_compound holds exported_lock for duration of compound
!  * processing.  This version doesn't manipulate exi_count
!  * since NFS4 breaks fundamental assumptions in the exi_count
!  * design.
   */
  struct exportinfo *
! checkexport4(fsid_t *fsid, fid_t *fid, vnode_t *vp)
  {
          struct exportinfo *exi;
  
!         ASSERT(RW_LOCK_HELD(&exported_lock));
! 
!         for (exi = exptable[exptablehash(fsid, fid)];
!             exi != NULL;
!             exi = exi->fid_hash.next) {
!                 if (exportmatch(exi, fsid, fid)) {
!                         /*
!                          * If this is the place holder for the
!                          * public file handle, then return the
!                          * real export entry for the public file
!                          * handle.
!                          */
!                         if (exi->exi_export.ex_flags & EX_PUBLIC) {
!                                 exi = exi_public;
!                         }
  
-                         /*
-                          * If vp is given, check if vp is the
-                          * same vnode as the exported node.
-                          *
-                          * Since VOP_FID of a lofs node returns the
-                          * fid of its real node (ufs), the exported
-                          * node for lofs and (pseudo) ufs may have
-                          * the same fsid and fid.
-                          */
-                         if (vp == NULL || vp == exi->exi_vp)
                                  return (exi);
-                 }
-         }
- 
-         return (NULL);
  }
  
  /*
   * Free an entire export list node
   */
--- 2445,2487 ----
                           */
                          if (exi->exi_export.ex_flags & EX_PUBLIC) {
                                  exi = exi_public;
                          }
  
!                         /*
!                          * If vp is given, check if vp is the
!                          * same vnode as the exported node.
!                          *
!                          * Since VOP_FID of a lofs node returns the
!                          * fid of its real node (ufs), the exported
!                          * node for lofs and (pseudo) ufs may have
!                          * the same fsid and fid.
!                          */
!                         if (vp == NULL || vp == exi->exi_vp) {
                                  return (exi);
                          }
                  }
!         }
          return (NULL);
  }
  
  /*
!  * Find the export structure associated with the given filesystem.
!  * If found, then increment the ref count (exi_count).
   */
  struct exportinfo *
! checkexport(fsid_t *fsid, fid_t *fid, vnode_t *vp)
  {
          struct exportinfo *exi;
  
!         rw_enter(&exported_lock, RW_READER);
!         exi = checkexport_nohold(fsid, fid, vp);
!         if (exi)
!                 exi_hold(exi);
!         rw_exit(&exported_lock);
  
          return (exi);
  }
  
  /*
   * Free an entire export list node
   */