PSARC 2008/290 lofi mount
6384817 Need persistent lofi based mounts and direct mount(1m) support for lofi

*** 17,31 ****
   * information: Portions Copyright [yyyy] [name of copyright owner]
   *
   * CDDL HEADER END
   */
  /*
!  * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
   * Use is subject to license terms.
   */
  
! #pragma ident   "@(#)pc_vfsops.c        1.104   07/10/25 SMI"
  
  #include <sys/param.h>
  #include <sys/systm.h>
  #include <sys/kmem.h>
  #include <sys/user.h>
--- 17,31 ----
   * information: Portions Copyright [yyyy] [name of copyright owner]
   *
   * CDDL HEADER END
   */
  /*
!  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
   * Use is subject to license terms.
   */
  
! #pragma ident   "@(#)pc_vfsops.c        1.105   08/05/07 SMI"
  
  #include <sys/param.h>
  #include <sys/systm.h>
  #include <sys/kmem.h>
  #include <sys/user.h>
*** 291,301 ****
          int *dos_ldrive,
          dev_t *xdev)
  {
          struct pathname special;
          char *c;
!         struct vnode *bvp;
          int oflag, aflag;
          int error;
  
          /*
           * Resolve path name of special file being mounted.
--- 291,302 ----
          int *dos_ldrive,
          dev_t *xdev)
  {
          struct pathname special;
          char *c;
!         struct vnode *svp = NULL;
!         struct vnode *lvp = NULL;
          int oflag, aflag;
          int error;
  
          /*
           * Resolve path name of special file being mounted.
*** 305,315 ****
          }
  
          *dos_ldrive = -1;
  
          if (error =
!             lookupname(special.pn_path, UIO_SYSSPACE, FOLLOW, NULLVPP, &bvp)) {
                  /*
                   * If there's no device node, the name specified most likely
                   * maps to a PCFS-style "partition specifier" to select a
                   * harddisk primary/logical partition. Disable floppy-specific
                   * checks in such cases unless an explicit :A or :B is
--- 306,316 ----
          }
  
          *dos_ldrive = -1;
  
          if (error =
!             lookupname(special.pn_path, UIO_SYSSPACE, FOLLOW, NULLVPP, &svp)) {
                  /*
                   * If there's no device node, the name specified most likely
                   * maps to a PCFS-style "partition specifier" to select a
                   * harddisk primary/logical partition. Disable floppy-specific
                   * checks in such cases unless an explicit :A or :B is
*** 382,392 ****
                          goto devlookup_done;
                  }
  
  
                  error = lookupname(special.pn_path, UIO_SYSSPACE, FOLLOW,
!                     NULLVPP, &bvp);
          } else {
                  *dos_ldrive = UNPARTITIONED_DRIVE;
          }
  devlookup_done:
          pn_free(&special);
--- 383,393 ----
                          goto devlookup_done;
                  }
  
  
                  error = lookupname(special.pn_path, UIO_SYSSPACE, FOLLOW,
!                     NULLVPP, &svp);
          } else {
                  *dos_ldrive = UNPARTITIONED_DRIVE;
          }
  devlookup_done:
          pn_free(&special);
*** 393,404 ****
          if (error)
                  return (error);
  
          ASSERT(*dos_ldrive >= UNPARTITIONED_DRIVE);
  
-         *xdev = bvp->v_rdev;
- 
          /*
           * Verify caller's permission to open the device special file.
           */
          if ((vfsp->vfs_flag & VFS_RDONLY) != 0 ||
              ((uap->flags & MS_RDONLY) != 0)) {
--- 394,403 ----
*** 407,430 ****
          } else {
                  oflag = FREAD | FWRITE;
                  aflag = VREAD | VWRITE;
          }
  
!         if (bvp->v_type != VBLK)
                  error = ENOTBLK;
-         else if (getmajor(*xdev) >= devcnt)
-                 error = ENXIO;
  
!         if ((error != 0) ||
!             (error = VOP_ACCESS(bvp, aflag, 0, cr, NULL)) != 0 ||
!             (error = secpolicy_spec_open(cr, bvp, oflag)) != 0) {
!                 VN_RELE(bvp);
!                 return (error);
          }
  
!         VN_RELE(bvp);
!         return (0);
  }
  
  static int
  pcfs_device_ismounted(
          struct vfs *vfsp,
--- 406,447 ----
          } else {
                  oflag = FREAD | FWRITE;
                  aflag = VREAD | VWRITE;
          }
  
!         error = vfs_get_lofi(vfsp, &lvp);
! 
!         if (error > 0) {
!                 if (error == ENOENT)
!                         error = ENODEV;
!                 goto out;
!         } else if (error == 0) {
!                 *xdev = lvp->v_rdev;
!         } else {
!                 *xdev = svp->v_rdev;
! 
!                 if (svp->v_type != VBLK)
                          error = ENOTBLK;
  
!                 if ((error = secpolicy_spec_open(cr, svp, oflag)) != 0)
!                         goto out;
          }
  
!         if (getmajor(*xdev) >= devcnt) {
!                 error = ENXIO;
!                 goto out;
!         }
! 
!         if ((error = VOP_ACCESS(svp, aflag, 0, cr, NULL)) != 0)
!                 goto out;
! 
! out:
!         if (svp != NULL)
!                 VN_RELE(svp);
!         if (lvp != NULL)
!                 VN_RELE(lvp);
!         return (error);
  }
  
  static int
  pcfs_device_ismounted(
          struct vfs *vfsp,