Filesystem: Reference counting for locations

 o A new data structure rtems_filesystem_global_location_t was
   introduced to be used for
    o the mount point location in the mount table entry,
    o the file system root location in the mount table entry,
    o the root directory location in the user environment, and
    o the current directory location in the user environment.
   During the path evaluation global start locations are obtained to
   ensure that the current file system instance will be not unmounted in
   the meantime.
 o The user environment uses now reference counting and is protected
   from concurrent access.
 o The path evaluation process was completely rewritten and simplified.
   The IMFS, RFS, NFS, and DOSFS use now a generic path evaluation
   method.  Recursive calls in the path evaluation have been replaced
   with iteration to avoid stack overflows.  Only the evaluation of
   symbolic links is recursive.  No dynamic memory allocations and
   intermediate buffers are used in the high level path evaluation.  No
   global locks are held during the file system instance specific path
   evaluation process.
 o Recursive symbolic link evaluation is now limited by
   RTEMS_FILESYSTEM_SYMLOOP_MAX.  Applications can retrieve this value
   via sysconf().
 o The device file system (devFS) uses now no global variables and
   allocation from the workspace.  Node names are allocated from the
   heap.
 o The upper layer lseek() performs now some parameter checks.
 o The upper layer ftruncate() performs now some parameter checks.
 o unmask() is now restricted to the RWX flags and protected from
   concurrent access.
 o The fchmod_h and rmnod_h file system node handlers are now a file
   system operation.
 o The unlink_h operation has been removed.  All nodes are now destroyed
   with the rmnod_h operation.
 o New lock_h, unlock_h, clonenod_h, and are_nodes_equal_h file system
   operations.
 o The path evaluation and file system operations are now protected by
   per file system instance lock and unlock operations.
 o Fix and test file descriptor duplicate in fcntl().
 o New test fstests/fsnofs01.

47 files changed, 2200 insertions, 1781 deletions

diff --git a/cpukit/libcsupport/src/__usrenv.c b/cpukit/libcsupport/src/__usrenv.c
index 0b3469fa1a..d26e73658f 100644
--- a/cpukit/libcsupport/src/__usrenv.c
+++ b/cpukit/libcsupport/src/__usrenv.c
@@ -2,6 +2,9 @@
  *  COPYRIGHT (c) 1989-2008.
  *  On-Line Applications Research Corporation (OAR).
  *
+ *  Modifications to support reference counting in the file system are
+ *  Copyright (c) 2012 embedded brains GmbH.
+ *
  *  The license and distribution terms for this file may be
  *  found in the file LICENSE in this distribution or at
  *  http://www.rtems.com/license/LICENSE.
@@ -10,18 +13,246 @@
  */
 
 #if HAVE_CONFIG_H
-#include "config.h"
+  #include "config.h"
 #endif
 
-#include <rtems.h>
-#include <rtems/libio.h>
+#include <sys/stat.h>
+
 #include <rtems/libio_.h>
 
-/*
- *  Global information for POSIX Process Environment Support
- */
+static int null_handler_open(
+  rtems_libio_t *iop,
+  const char *path,
+  int oflag,
+  mode_t mode
+)
+{
+  return -1;
+}
+
+static int null_handler_fstat(
+  const rtems_filesystem_location_info_t *pathloc,
+  struct stat *buf
+)
+{
+  return -1;
+}
+
+const rtems_filesystem_file_handlers_r rtems_filesystem_null_handlers = {
+  .open_h = null_handler_open,
+  .close_h = rtems_filesystem_default_close,
+  .read_h = rtems_filesystem_default_read,
+  .write_h = rtems_filesystem_default_write,
+  .ioctl_h = rtems_filesystem_default_ioctl,
+  .lseek_h = rtems_filesystem_default_lseek,
+  .fstat_h = null_handler_fstat,
+  .ftruncate_h = rtems_filesystem_default_ftruncate,
+  .fsync_h = rtems_filesystem_default_fsync,
+  .fdatasync_h = rtems_filesystem_default_fdatasync,
+  .fcntl_h = rtems_filesystem_default_fcntl
+};
+
+static void null_op_lock_or_unlock(
+  rtems_filesystem_mount_table_entry_t *mt_entry
+)
+{
+  /* Do nothing */
+}
+
+static int null_op_mknod(
+  const rtems_filesystem_location_info_t *parentloc,
+  const char *name,
+  size_t namelen,
+  mode_t mode,
+  dev_t dev
+)
+{
+  return -1;
+}
+
+static int null_op_rmnod(
+  const rtems_filesystem_location_info_t *parentloc,
+  const rtems_filesystem_location_info_t *loc
+)
+{
+  return -1;
+}
+
+static int null_op_link(
+  const rtems_filesystem_location_info_t *parentloc,
+  const rtems_filesystem_location_info_t *targetloc,
+  const char *name,
+  size_t namelen
+)
+{
+  return -1;
+}
+
+static int null_op_fchmod(
+  const rtems_filesystem_location_info_t *pathloc,
+  mode_t mode
+)
+{
+  return -1;
+}
+
+static int null_op_chown(
+  const rtems_filesystem_location_info_t *loc,
+  uid_t owner,
+  gid_t group
+)
+{
+  return -1;
+}
+
+static int null_op_clonenode(
+  rtems_filesystem_location_info_t *loc
+)
+{
+  return -1;
+}
+
+static int null_op_mount(
+  rtems_filesystem_mount_table_entry_t *mt_entry
+)
+{
+  return -1;
+}
+
+static int null_op_fsmount_me(
+  rtems_filesystem_mount_table_entry_t *mt_entry,
+  const void *data
+)
+{
+  return -1;
+}
+
+static int null_op_unmount(
+  rtems_filesystem_mount_table_entry_t *mt_entry
+)
+{
+  return -1;
+}
+
+static void null_op_fsunmount_me(
+  rtems_filesystem_mount_table_entry_t *mt_entry
+)
+{
+  /* Do nothing */
+}
+
+static int null_op_utime(
+  const rtems_filesystem_location_info_t *loc,
+  time_t actime,
+  time_t modtime
+)
+{
+  return -1;
+}
+
+static int null_op_symlink(
+  const rtems_filesystem_location_info_t *parentloc,
+  const char *name,
+  size_t namelen,
+  const char *target
+)
+{
+  return -1;
+}
+
+static ssize_t null_op_readlink(
+  const rtems_filesystem_location_info_t *loc,
+  char *buf,
+  size_t bufsize
+)
+{
+  return -1;
+}
+
+static int null_op_rename(
+  const rtems_filesystem_location_info_t *oldparentloc,
+  const rtems_filesystem_location_info_t *oldloc,
+  const rtems_filesystem_location_info_t *newparentloc,
+  const char *name,
+  size_t namelen
+)
+{
+  return -1;
+}
+
+static int null_op_statvfs(
+  const rtems_filesystem_location_info_t *loc,
+  struct statvfs *buf
+)
+{
+  return -1;
+}
+
+static const rtems_filesystem_operations_table null_ops = {
+  .lock_h = null_op_lock_or_unlock,
+  .unlock_h = null_op_lock_or_unlock,
+  .eval_path_h = rtems_filesystem_default_eval_path,
+  .link_h = null_op_link,
+  .are_nodes_equal_h = rtems_filesystem_default_are_nodes_equal,
+  .node_type_h = rtems_filesystem_default_node_type,
+  .mknod_h = null_op_mknod,
+  .rmnod_h = null_op_rmnod,
+  .fchmod_h = null_op_fchmod,
+  .chown_h = null_op_chown,
+  .clonenod_h = null_op_clonenode,
+  .freenod_h = rtems_filesystem_default_freenode,
+  .mount_h = null_op_mount,
+  .fsmount_me_h = null_op_fsmount_me,
+  .unmount_h = null_op_unmount,
+  .fsunmount_me_h = null_op_fsunmount_me,
+  .utime_h = null_op_utime,
+  .symlink_h = null_op_symlink,
+  .readlink_h = null_op_readlink,
+  .rename_h = null_op_rename,
+  .statvfs_h = null_op_statvfs
+};
+
+rtems_filesystem_mount_table_entry_t rtems_filesystem_null_mt_entry = {
+  .location_chain = {
+    .Head = {
+      .Node = {
+        .next = &rtems_filesystem_global_location_null.location.mt_entry_node,
+        .previous = NULL
+      },
+      .fill = &rtems_filesystem_global_location_null.location.mt_entry_node,
+    }
+  },
+  .mt_point_node = &rtems_filesystem_global_location_null,
+  .mt_fs_root = &rtems_filesystem_global_location_null,
+  .mounted = false,
+  .writeable = false
+};
+
+rtems_filesystem_global_location_t rtems_filesystem_global_location_null = {
+  .location = {
+    .mt_entry_node = {
+      .next = &rtems_filesystem_null_mt_entry.location_chain.Tail.Node,
+      .previous = &rtems_filesystem_null_mt_entry.location_chain.Head.Node
+    },
+    .handlers = &rtems_filesystem_null_handlers,
+    .ops = &null_ops,
+    .mt_entry = &rtems_filesystem_null_mt_entry
+  },
 
-rtems_user_env_t   rtems_global_user_env;
-rtems_user_env_t * rtems_current_user_env = &rtems_global_user_env;
+  /*
+   * The initial reference count accounts for the following references
+   *  o the root directory of the user environment,
+   *  o the current directory of the user environment,
+   *  o the root node of the null file system instance, and
+   *  o the mount point node of the null file system instance.
+   */
+  .reference_count = 4
+};
 
+rtems_user_env_t rtems_global_user_env = {
+  .current_directory = &rtems_filesystem_global_location_null,
+  .root_directory = &rtems_filesystem_global_location_null,
+  .umask = S_IWGRP | S_IWOTH
+};
 
+rtems_user_env_t *rtems_current_user_env = &rtems_global_user_env;
diff --git a/cpukit/libcsupport/src/_rename_r.c b/cpukit/libcsupport/src/_rename_r.c
index 51010df28e..7a2637aa89 100644
--- a/cpukit/libcsupport/src/_rename_r.c
+++ b/cpukit/libcsupport/src/_rename_r.c
@@ -4,6 +4,9 @@
  *  COPYRIGHT (c) 1989-2007.
  *  On-Line Applications Research Corporation (OAR).
  *
+ *  Modifications to support reference counting in the file system are
+ *  Copyright (c) 2012 embedded brains GmbH.
+ *
  *  The license and distribution terms for this file may be
  *  found in the file LICENSE in this distribution or at
  *  http://www.rtems.com/license/LICENSE.
@@ -16,12 +19,10 @@
 #endif
 
 #if defined(RTEMS_NEWLIB) && !defined(HAVE__RENAME_R)
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <unistd.h>
+
+#include <stdio.h>
 
 #include <rtems/libio_.h>
-#include <rtems/seterr.h>
 
 int _rename_r(
   struct _reent *ptr __attribute__((unused)),
@@ -29,85 +30,47 @@ int _rename_r(
   const char    *new
 )
 {
-  int                                 old_parent_pathlen;
-  rtems_filesystem_location_info_t    old_loc;
-  rtems_filesystem_location_info_t    old_parent_loc;
-  rtems_filesystem_location_info_t    new_parent_loc;
-  int                                 i;
-  int                                 result;
-  const char                         *name;
-  bool                                free_old_parentloc = false;
-
-  /*
-   *  Get the parent node of the old path to be renamed. Find the parent path.
-   */
-
-  old_parent_pathlen = rtems_filesystem_dirname ( old );
-
-  if ( old_parent_pathlen == 0 )
-    rtems_filesystem_get_start_loc( old, &i, &old_parent_loc );
-  else {
-    result = rtems_filesystem_evaluate_path( old, old_parent_pathlen,
-                                             RTEMS_LIBIO_PERMS_WRITE,
-                                             &old_parent_loc,
-                                             false );
-    if ( result != 0 )
-      return -1;
-
-    free_old_parentloc = true;
+  int rv = 0;
+  rtems_filesystem_eval_path_context_t old_ctx;
+  int old_eval_flags = 0;
+  rtems_filesystem_location_info_t old_parentloc;
+  int old_parent_eval_flags = RTEMS_LIBIO_PERMS_WRITE
+    | RTEMS_LIBIO_FOLLOW_HARD_LINK;
+  const rtems_filesystem_location_info_t *old_currentloc =
+    rtems_filesystem_eval_path_start_with_parent(
+      &old_ctx,
+      old,
+      old_eval_flags,
+      &old_parentloc,
+      old_parent_eval_flags
+    );
+  rtems_filesystem_eval_path_context_t new_ctx;
+
+  /* FIXME: This is not POSIX conform */
+  int new_eval_flags = RTEMS_LIBIO_FOLLOW_HARD_LINK
+    | RTEMS_LIBIO_MAKE
+    | RTEMS_LIBIO_EXCLUSIVE;
+
+  const rtems_filesystem_location_info_t *new_currentloc =
+    rtems_filesystem_eval_path_start( &new_ctx, new, new_eval_flags );
+
+  rv = rtems_filesystem_location_exists_in_same_fs_instance_as(
+    old_currentloc,
+    new_currentloc
+  );
+  if ( rv == 0 ) {
+    rv = (*new_currentloc->ops->rename_h)(
+      &old_parentloc,
+      old_currentloc,
+      new_currentloc,
+      rtems_filesystem_eval_path_get_token( &new_ctx ),
+      rtems_filesystem_eval_path_get_tokenlen( &new_ctx )
+    );
   }
 
-  /*
-   * Start from the parent to find the node that should be under it.
-   */
-
-  old_loc = old_parent_loc;
-  name = old + old_parent_pathlen;
-  name += rtems_filesystem_prefix_separators( name, strlen( name ) );
-
-  result = rtems_filesystem_evaluate_relative_path( name , strlen( name ),
-                                                    0, &old_loc, false );
-  if ( result != 0 ) {
-    if ( free_old_parentloc )
-      rtems_filesystem_freenode( &old_parent_loc );
-    return -1;
-  }
-  
-  /*
-   * Get the parent of the new node we are renaming to.
-   */
-
-  rtems_filesystem_get_start_loc( new, &i, &new_parent_loc );
-
-  result = (*new_parent_loc.ops->evalformake_h)( &new[i], &new_parent_loc, &name );
-  if ( result != 0 ) {
-    rtems_filesystem_freenode( &new_parent_loc );
-    if ( free_old_parentloc )
-      rtems_filesystem_freenode( &old_parent_loc );
-    rtems_filesystem_freenode( &old_loc );
-    return -1;
-  }
-
-  /*
-   *  Check to see if the caller is trying to rename across file system
-   *  boundaries.
-   */
-
-  if ( old_parent_loc.mt_entry != new_parent_loc.mt_entry ) {
-    rtems_filesystem_freenode( &new_parent_loc );
-    if ( free_old_parentloc )
-      rtems_filesystem_freenode( &old_parent_loc );
-    rtems_filesystem_freenode( &old_loc );
-    rtems_set_errno_and_return_minus_one( EXDEV );
-  }
-
-  result = (*new_parent_loc.ops->rename_h)( &old_parent_loc, &old_loc, &new_parent_loc, name );
-
-  rtems_filesystem_freenode( &new_parent_loc );
-  if ( free_old_parentloc )
-    rtems_filesystem_freenode( &old_parent_loc );
-  rtems_filesystem_freenode( &old_loc );
+  rtems_filesystem_eval_path_cleanup_with_parent( &old_ctx, &old_parentloc );
+  rtems_filesystem_eval_path_cleanup( &new_ctx );
 
-  return result;
+  return rv;
 }
 #endif
diff --git a/cpukit/libcsupport/src/base_fs.c b/cpukit/libcsupport/src/base_fs.c
index b5681eda63..bbf6d8d4be 100644
--- a/cpukit/libcsupport/src/base_fs.c
+++ b/cpukit/libcsupport/src/base_fs.c
@@ -4,6 +4,9 @@
  *  COPYRIGHT (c) 1989-2008.
  *  On-Line Applications Research Corporation (OAR).
  *
+ *  Modifications to support reference counting in the file system are
+ *  Copyright (c) 2012 embedded brains GmbH.
+ *
  *  The license and distribution terms for this file may be
  *  found in the file LICENSE in this distribution or at
  *  http://www.rtems.com/license/LICENSE.
@@ -35,62 +38,20 @@
 
 void rtems_filesystem_initialize( void )
 {
-  int                                   status;
-  const rtems_filesystem_mount_table_t *mt;
-  rtems_filesystem_location_info_t      loc;
-
-  /*
-   *  Set the default umask to "022".
-   */
-
-  rtems_filesystem_umask = 022;
-
-  /*
-   *  mount the first filesystem.
-   */
-  if ( rtems_filesystem_mount_table_size == 0 )
-    rtems_fatal_error_occurred( 0xABCD0001 );
-
-  mt = &rtems_filesystem_mount_table[0];
-
-  status = mount( mt->device, mt->mount_point, mt->type, mt->fsoptions, NULL );
-  if ( status == -1 )
+  int rv = 0;
+  const rtems_filesystem_mount_configuration *root_config =
+    &rtems_filesystem_root_configuration;
+
+  rv = mount(
+    root_config->source,
+    root_config->target,
+    root_config->filesystemtype,
+    root_config->options,
+    root_config->data
+  );
+  if ( rv != 0 )
     rtems_fatal_error_occurred( 0xABCD0002 );
 
-  rtems_filesystem_link_counts = 0;
-
-  /* setup the 'current' and 'root' directories
-   *
-   * NOTE: cloning the pathlocs is not strictly
-   *       necessary. Since we implicitely let
-   *       all threads that don't call
-   *       libio_set_private_env() share the same
-   *       (initial) 'root' and 'current' locs,
-   *       we (also implicitely) assume that the
-   *       root filesystem doesn't care about
-   *       reference counts.
-   *       I just inserted the code snippet below
-   *       to remind everybody of the fact by
-   *       making it more explicit...
-   *       Ideally, every thread would have to
-   *       call either share_private_env() or
-   *       set_private_env() - but then: that's
-   *       gonna hit performance.
-   *
-   *       Till Straumann, 10/25/2002
-   */
-  /* Clone the root pathloc */
-  rtems_filesystem_evaluate_path("/", 1, 0, &loc, 0);
-  rtems_filesystem_root        = loc;
-  /* One more clone for the current node */
-  rtems_filesystem_evaluate_path("/", 1, 0, &loc, 0);
-  rtems_filesystem_current     = loc;
-
-  /* Note: the global_env's refcnt doesn't matter
-   * as the global env is never released
-   */
-
-
   /*
    *  Traditionally RTEMS devices are under "/dev" so install this directory.
    *
@@ -100,8 +61,8 @@ void rtems_filesystem_initialize( void )
    *        created that way by the IMFS.
    */
 
-  status = mkdir( "/dev", 0777);
-  if ( status != 0 )
+  rv = mkdir( "/dev", 0777);
+  if ( rv != 0 )
     rtems_fatal_error_occurred( 0xABCD0003 );
 
   /*
diff --git a/cpukit/libcsupport/src/chdir.c b/cpukit/libcsupport/src/chdir.c
index c9d05f0bef..df65170936 100644
--- a/cpukit/libcsupport/src/chdir.c
+++ b/cpukit/libcsupport/src/chdir.c
@@ -4,6 +4,9 @@
  *  COPYRIGHT (c) 1989-2010.
  *  On-Line Applications Research Corporation (OAR).
  *
+ *  Modifications to support reference counting in the file system are
+ *  Copyright (c) 2012 embedded brains GmbH.
+ *
  *  The license and distribution terms for this file may be
  *  found in the file LICENSE in this distribution or at
  *  http://www.rtems.com/license/LICENSE.
@@ -12,46 +15,47 @@
  */
 
 #if HAVE_CONFIG_H
-#include "config.h"
+  #include "config.h"
 #endif
 
-#include <rtems.h>
-
 #include <unistd.h>
-#include <errno.h>
 
 #include <rtems/libio_.h>
-#include <rtems/seterr.h>
 
-int chdir(
-  const char *pathname
-)
+int rtems_filesystem_chdir( rtems_filesystem_location_info_t *loc )
 {
-  rtems_filesystem_location_info_t  loc;
-  int                               result;
-
-  if ( !pathname )
-    rtems_set_errno_and_return_minus_one( EFAULT );
-
-  /*
-   *  Get the node where we wish to go.
-   */
-  result = rtems_filesystem_evaluate_path(
-    pathname, strlen( pathname ), RTEMS_LIBIO_PERMS_SEARCH, &loc, true );
-  if ( result != 0 )
-     return -1;
-
-  /*
-   * Verify you can change directory into this node.
-   */
-  if (  (*loc.ops->node_type_h)( &loc ) != RTEMS_FILESYSTEM_DIRECTORY ) {
-    rtems_filesystem_freenode( &loc );
-    rtems_set_errno_and_return_minus_one( ENOTDIR );
+  int rv = 0;
+  rtems_filesystem_global_location_t *global_loc =
+    rtems_filesystem_location_transform_to_global( loc );
+  rtems_filesystem_node_types_t type =
+    rtems_filesystem_node_type( &global_loc->location );
+
+  if ( type == RTEMS_FILESYSTEM_DIRECTORY ) {
+    rtems_filesystem_global_location_assign(
+      &rtems_filesystem_current,
+      global_loc
+    );
+  } else {
+    rtems_filesystem_location_error( &global_loc->location, ENOTDIR );
+    rtems_filesystem_global_location_release( global_loc );
+    rv = -1;
   }
 
-  rtems_filesystem_freenode( &rtems_filesystem_current );
-
-  rtems_filesystem_current = loc;
+  return rv;
+}
 
-  return 0;
+int chdir( const char *path )
+{
+  int rv = 0;
+  rtems_filesystem_eval_path_context_t ctx;
+  int eval_flags = RTEMS_LIBIO_PERMS_EXEC
+    | RTEMS_LIBIO_FOLLOW_LINK;
+  rtems_filesystem_location_info_t pathloc;
+
+  rtems_filesystem_eval_path_start( &ctx, path, eval_flags );
+  rtems_filesystem_eval_path_extract_currentloc( &ctx, &pathloc );
+  rv = rtems_filesystem_chdir( &pathloc );
+  rtems_filesystem_eval_path_cleanup( &ctx );
+
+  return rv;
 }
diff --git a/cpukit/libcsupport/src/chmod.c b/cpukit/libcsupport/src/chmod.c
index d1d9ae0f5f..ff3039a557 100644
--- a/cpukit/libcsupport/src/chmod.c
+++ b/cpukit/libcsupport/src/chmod.c
@@ -12,35 +12,24 @@
  */
 
 #if HAVE_CONFIG_H
-#include "config.h"
+  #include "config.h"
 #endif
 
-#include <rtems.h>
-#include <rtems/libio.h>
 #include <sys/stat.h>
-#include <fcntl.h>
-#include <errno.h>
-#include <unistd.h>
 
 #include <rtems/libio_.h>
-#include <rtems/seterr.h>
 
-int chmod(
-  const char *path,
-  mode_t      mode
-)
+int chmod( const char *path, mode_t mode )
 {
-  int                              status;
-  rtems_filesystem_location_info_t loc;
-  int                              result;
+  int rv = 0;
+  rtems_filesystem_eval_path_context_t ctx;
+  int eval_flags = RTEMS_LIBIO_FOLLOW_LINK;
+  const rtems_filesystem_location_info_t *currentloc =
+    rtems_filesystem_eval_path_start( &ctx, path, eval_flags );
 
-  status = rtems_filesystem_evaluate_path( path, strlen( path ), 0, &loc, true );
-  if ( status != 0 )
-    return -1;
+  rv = (*currentloc->ops->fchmod_h)( currentloc, mode );
 
-  result = (*loc.handlers->fchmod_h)( &loc, mode );
+  rtems_filesystem_eval_path_cleanup( &ctx );
 
-  rtems_filesystem_freenode( &loc );
-
-  return result;
+  return rv;
 }
diff --git a/cpukit/libcsupport/src/chown.c b/cpukit/libcsupport/src/chown.c
index 9ecaea11f7..1d07384d7d 100644
--- a/cpukit/libcsupport/src/chown.c
+++ b/cpukit/libcsupport/src/chown.c
@@ -4,6 +4,9 @@
  *  COPYRIGHT (c) 1989-1999.
  *  On-Line Applications Research Corporation (OAR).
  *
+ *  Modifications to support reference counting in the file system are
+ *  Copyright (c) 2012 embedded brains GmbH.
+ *
  *  The license and distribution terms for this file may be
  *  found in the file LICENSE in this distribution or at
  *  http://www.rtems.com/license/LICENSE.
@@ -12,39 +15,38 @@
  */
 
 #if HAVE_CONFIG_H
-#include "config.h"
+  #include "config.h"
 #endif
 
 #include <unistd.h>
 
-#include <rtems.h>
 #include <rtems/libio_.h>
 
-int _chown_helper(
+int rtems_filesystem_chown(
   const char *path,
-  uid_t       owner,
-  gid_t       group,
-  int         follow_link
+  uid_t owner,
+  gid_t group,
+  int eval_follow_link
 )
 {
-  rtems_filesystem_location_info_t   loc;
-  int                                result;
-
-  if ( rtems_filesystem_evaluate_path( path, strlen( path ), 0x00, &loc, follow_link ) )
-    return -1;
+  int rv = 0;
+  rtems_filesystem_eval_path_context_t ctx;
+  int eval_flags = eval_follow_link;
+  const rtems_filesystem_location_info_t *currentloc =
+    rtems_filesystem_eval_path_start( &ctx, path, eval_flags );
 
-  result = (*loc.ops->chown_h)( &loc, owner, group );
+  rv = (*currentloc->ops->chown_h)(
+    currentloc,
+    owner,
+    group
+  );
 
-  rtems_filesystem_freenode( &loc );
+  rtems_filesystem_eval_path_cleanup( &ctx );
 
-  return result;
+  return rv;
 }
 
-int chown(
-  const char *path,
-  uid_t       owner,
-  gid_t       group
-)
+int chown( const char *path, uid_t owner, gid_t group )
 {
-  return _chown_helper( path, owner, group, true );
+  return rtems_filesystem_chown( path, owner, group, RTEMS_LIBIO_FOLLOW_LINK );
 }
diff --git a/cpukit/libcsupport/src/chroot.c b/cpukit/libcsupport/src/chroot.c
index ccda4d6d7a..fd802ff32b 100644
--- a/cpukit/libcsupport/src/chroot.c
+++ b/cpukit/libcsupport/src/chroot.c
@@ -5,6 +5,9 @@
  *  COPYRIGHT (c) 1989-2008.
  *  On-Line Applications Research Corporation (OAR).
  *
+ *  Modifications to support reference counting in the file system are
+ *  Copyright (c) 2012 embedded brains GmbH.
+ *
  *  The license and distribution terms for this file may be
  *  found in the file LICENSE in this distribution or at
  *  http://www.rtems.com/license/LICENSE.
@@ -13,43 +16,77 @@
  */
 
 #if HAVE_CONFIG_H
-#include "config.h"
+  #include "config.h"
 #endif
 
-#include <rtems.h>
-
 #include <unistd.h>
-#include <errno.h>
 
 #include <rtems/libio_.h>
-#include <rtems/seterr.h>
 
-int chroot(
-  const char *pathname
-)
+int chroot( const char *path )
 {
-  int                               result;
-  rtems_filesystem_location_info_t  loc;
-
-  /* an automatic call to new private env the first time */
-  if (rtems_current_user_env == &rtems_global_user_env) {
-   rtems_libio_set_private_env(); /* try to set a new private env*/
-   if (rtems_current_user_env == &rtems_global_user_env) /* not ok */
-    rtems_set_errno_and_return_minus_one( ENOTSUP );
-  }
+  int rv = 0;
+  rtems_status_code sc = RTEMS_SUCCESSFUL;
+  rtems_filesystem_eval_path_context_t ctx;
+  int eval_flags = RTEMS_LIBIO_PERMS_SEARCH
+    | RTEMS_LIBIO_FOLLOW_LINK;
+  rtems_filesystem_location_info_t loc;
+  rtems_filesystem_global_location_t *new_current_loc;
+
+  /*
+   * We use the global environment for path evaluation.  This makes it possible
+   * to escape from a chroot environment referencing an unmounted file system.
+   */
+  rtems_filesystem_eval_path_start_with_root_and_current(
+    &ctx,
+    path,
+    eval_flags,
+    &rtems_global_user_env.root_directory,
+    &rtems_global_user_env.current_directory
+  );
 
-  result = chdir(pathname);
-  if (result) {
-    rtems_set_errno_and_return_minus_one( errno );
+  rtems_filesystem_eval_path_extract_currentloc( &ctx, &loc );
+  new_current_loc = rtems_filesystem_location_transform_to_global( &loc );
+  if ( !rtems_filesystem_global_location_is_null( new_current_loc ) ) {
+    rtems_filesystem_global_location_t *new_root_loc =
+      rtems_filesystem_global_location_obtain( &new_current_loc );
+    rtems_filesystem_node_types_t type =
+      (*new_root_loc->location.ops->node_type_h)( &new_root_loc->location );
+
+    if ( type == RTEMS_FILESYSTEM_DIRECTORY ) {
+      sc = rtems_libio_set_private_env();
+      if (sc == RTEMS_SUCCESSFUL) {
+        rtems_filesystem_global_location_assign(
+          &rtems_filesystem_root,
+          new_root_loc
+        );
+        rtems_filesystem_global_location_assign(
+          &rtems_filesystem_current,
+          new_current_loc
+        );
+      } else {
+        if (sc != RTEMS_UNSATISFIED) {
+          errno = ENOMEM;
+        }
+        rv = -1;
+      }
+    } else {
+      rtems_filesystem_location_error( &new_root_loc->location, ENOTDIR );
+      rv = -1;
+    }
+
+    if ( rv != 0 ) {
+      rtems_filesystem_global_location_release( new_root_loc );
+    }
+  } else {
+    rv = -1;
   }
 
-  /* clone the new root location */
-  if (rtems_filesystem_evaluate_path(".", 1, 0, &loc, 0)) {
-    /* our cwd has changed, though - but there is no easy way of return :-( */
-    rtems_set_errno_and_return_minus_one( errno );
+  rtems_filesystem_eval_path_cleanup( &ctx );
+
+  if ( rv != 0 ) {
+    rtems_filesystem_global_location_release( new_current_loc );
   }
-  rtems_filesystem_freenode(&rtems_filesystem_root);
-  rtems_filesystem_root = loc;
 
-  return 0;
+  return rv;
 }
diff --git a/cpukit/libcsupport/src/clonenode.c b/cpukit/libcsupport/src/clonenode.c
new file mode 100644
index 0000000000..380ad90699
--- /dev/null
+++ b/cpukit/libcsupport/src/clonenode.c
@@ -0,0 +1,34 @@
+/*
+ * Copyright (c) 2012 embedded brains GmbH.  All rights reserved.
+ *
+ *  embedded brains GmbH
+ *  Obere Lagerstr. 30
+ *  82178 Puchheim
+ *  Germany
+ *  <rtems@embedded-brains.de>
+ *
+ * The license and distribution terms for this file may be
+ * found in the file LICENSE in this distribution or at
+ * http://www.rtems.com/license/LICENSE.
+ */
+
+#if HAVE_CONFIG_H
+  #include "config.h"
+#endif
+
+#include <rtems/libio_.h>
+
+void rtems_filesystem_location_clone(
+  rtems_filesystem_location_info_t *clone,
+  const rtems_filesystem_location_info_t *master
+)
+{
+  int rv = 0;
+
+  clone = rtems_filesystem_location_copy( clone, master );
+  rv = (*clone->ops->clonenod_h)( clone );
+  if ( rv != 0 ) {
+    rtems_filesystem_location_remove_from_mt_entry( clone );
+    rtems_filesystem_location_initialize_to_null( clone );
+  }
+}
diff --git a/cpukit/libcsupport/src/close.c b/cpukit/libcsupport/src/close.c
index 726bca11d9..3cdd0bffba 100644
--- a/cpukit/libcsupport/src/close.c
+++ b/cpukit/libcsupport/src/close.c
@@ -22,16 +22,14 @@ int close(
 )
 {
   rtems_libio_t      *iop;
-  rtems_status_code   rc;
+  int                 rc;
 
   rtems_libio_check_fd(fd);
   iop = rtems_libio_iop(fd);
   rtems_libio_check_is_open(iop);
 
-  rc = RTEMS_SUCCESSFUL;
   rc = (*iop->pathinfo.handlers->close_h)( iop );
 
-  rtems_filesystem_freenode( &iop->pathinfo );
   rtems_libio_free( iop );
 
   return rc;
diff --git a/cpukit/libcsupport/src/eval.c b/cpukit/libcsupport/src/eval.c
deleted file mode 100644
index 5a9118d3e1..0000000000
--- a/cpukit/libcsupport/src/eval.c
+++ /dev/null
@@ -1,151 +0,0 @@
-/*
- *  rtems_filesystem_evaluate_path()
- *
- *  Routine to seed the evaluate path routine.
- *
- *  COPYRIGHT (c) 1989-2010.
- *  On-Line Applications Research Corporation (OAR).
- *
- *  The license and distribution terms for this file may be
- *  found in the file LICENSE in this distribution or at
- *  http://www.rtems.com/license/LICENSE.
- *
- *  $Id$
- */
-
-#if HAVE_CONFIG_H
-#include "config.h"
-#endif
-
-#include <rtems.h>
-#include <rtems/libio_.h>
-#include <rtems/seterr.h>
-
-int rtems_filesystem_evaluate_relative_path(
-  const char                        *pathname,
-  size_t                             pathnamelen,
-  int                                flags,
-  rtems_filesystem_location_info_t  *pathloc,
-  int                                follow_link
-)
-{
-  int                           result;
-  rtems_filesystem_node_types_t type;
-
-  #if defined(RTEMS_DEBUG)
-    /*
-     * Verify Input parameters that should never be bad unless someone
-     * is implementing a new filesystem and has bugs.
-     */
-    if ( !pathname )
-      rtems_set_errno_and_return_minus_one( EFAULT );
-
-    if ( !pathloc )
-      rtems_set_errno_and_return_minus_one( EIO );
-  #endif
-
-  result = (*pathloc->ops->evalpath_h)( pathname, pathnamelen, flags, pathloc );
-
-  /*
-   * Get the Node type and determine if you need to follow the link or
-   * not.
-   */
-
-  if ( (result == 0) && follow_link ) {
-
-    type = (*pathloc->ops->node_type_h)( pathloc );
-
-    if ( ( type == RTEMS_FILESYSTEM_HARD_LINK ) ||
-         ( type == RTEMS_FILESYSTEM_SYM_LINK ) ) {
-
-        /* what to do with the valid node pathloc points to
-         * if eval_link_h fails?
-         * Let the FS implementation deal with this case.  It
-         * should probably free pathloc in either case:
-         *  - if the link evaluation fails, it must free the
-         *    original (valid) pathloc because we are going
-         *    to return -1 and hence the FS generics won't
-         *    cleanup pathloc.
-         *  - if the link evaluation is successful, the updated
-         *    pathloc will be passed up (and eventually released).
-         *    Hence, the (valid) originial node that we submit to
-         *    eval_link_h() should be released by the handler.
-         */
-
-        result =  (*pathloc->ops->eval_link_h)( pathloc, flags );
-    }
-  }
-
-  return result;
-}
-
-int rtems_filesystem_evaluate_path(
-  const char                        *pathname,
-  size_t                             pathnamelen,
-  int                                flags,
-  rtems_filesystem_location_info_t  *pathloc,
-  int                                follow_link
-)
-{
-  int                           i = 0;
-
-  #if defined(RTEMS_DEBUG)
-    /*
-     * Verify Input parameters that should never be bad unless someone
-     * is implementing a new filesystem and has bugs.
-     */
-    if ( !pathname )
-      rtems_set_errno_and_return_minus_one( EFAULT );
-
-    if ( !pathloc )
-      rtems_set_errno_and_return_minus_one( EIO );
-  #endif
-
-  /*
-   * Evaluate the path using the optable evalpath.
-   */
-
-  rtems_filesystem_get_start_loc( pathname, &i, pathloc );
-
-  /*
-   * We evaluation the path relative to the start location we get got.
-   */
-  return rtems_filesystem_evaluate_relative_path( &pathname[i],
-                                                  pathnamelen - i,
-                                                  flags,
-                                                  pathloc,
-                                                  follow_link );
-}
-
-int rtems_filesystem_dirname(
-  const char  *pathname
-)
-{
-  int len = strlen( pathname );
-
-  while ( len ) {
-    len--;
-    if ( rtems_filesystem_is_separator( pathname[len] ) )
-      break;
-  }
-
-  return len;
-}
-
-int rtems_filesystem_prefix_separators(
-  const char  *pathname,
-  int          pathnamelen
-)
-{
-  /*
-   * Eat any separators at start of the path.
-   */
-  int stripped = 0;
-  while ( *pathname && pathnamelen && rtems_filesystem_is_separator( *pathname ) )
-  {
-    pathname++;
-    pathnamelen--;
-    stripped++;
-  }
-  return stripped;
-}
diff --git a/cpukit/libcsupport/src/fchdir.c b/cpukit/libcsupport/src/fchdir.c
index c95e2b7fb3..7b64ea8f21 100644
--- a/cpukit/libcsupport/src/fchdir.c
+++ b/cpukit/libcsupport/src/fchdir.c
@@ -4,6 +4,9 @@
  *  COPYRIGHT (c) 1989-2011.
  *  On-Line Applications Research Corporation (OAR).
  *
+ *  Modifications to support reference counting in the file system are
+ *  Copyright (c) 2012 embedded brains GmbH.
+ *
  *  The license and distribution terms for this file may be
  *  found in the file LICENSE in this distribution or at
  *  http://www.rtems.com/license/LICENSE.
@@ -12,65 +15,50 @@
  */
 
 #if HAVE_CONFIG_H
-#include "config.h"
+  #include "config.h"
 #endif
 
 #include <unistd.h>
-#include <sys/stat.h>
-#include <errno.h>
 
-#include <rtems.h>
-#include <rtems/libio.h>
 #include <rtems/libio_.h>
-#include <rtems/seterr.h>
 
-int fchdir(
-  int       fd
-)
+int fchdir( int fd )
 {
+  int rv = 0;
   rtems_libio_t *iop;
-  rtems_filesystem_location_info_t loc, saved;
+  struct stat st;
+  rtems_filesystem_location_info_t loc;
+
+  st.st_mode = 0;
+  st.st_uid = 0;
+  st.st_gid = 0;
 
   rtems_libio_check_fd( fd );
   iop = rtems_libio_iop( fd );
-  rtems_libio_check_is_open(iop);
+  rtems_libio_check_is_open( iop );
 
-  /*
-   * Verify you can change directory into this node.
-   */
+  rtems_filesystem_instance_lock( &iop->pathinfo );
+  rv = (*iop->pathinfo.handlers->fstat_h)( &iop->pathinfo, &st );
+  if ( rv == 0 ) {
+    bool access_ok = rtems_filesystem_check_access(
+      RTEMS_LIBIO_PERMS_EXEC,
+      st.st_mode,
+      st.st_uid,
+      st.st_gid
+    );
 
-  if (  (*iop->pathinfo.ops->node_type_h)( &iop->pathinfo ) !=
-                                          RTEMS_FILESYSTEM_DIRECTORY ) {
-    rtems_set_errno_and_return_minus_one( ENOTDIR );
+    if ( access_ok ) {
+      rtems_filesystem_location_clone( &loc, &iop->pathinfo );
+    } else {
+      errno = EACCES;
+      rv = -1;
+    }
   }
+  rtems_filesystem_instance_unlock( &iop->pathinfo );
 
-
-  /*
-   * FIXME : I feel there should be another call to
-   *         actually take into account the extra reference to
-   *         this node which we are making here. I can
-   *         see the freenode interface but do not see
-   *         allocnode node interface. It maybe node_type.
-   *
-   * FIXED:  T.Straumann: it is evaluate_path()
-   *         but note the race condition. Threads who
-   *         share their rtems_filesystem_current better
-   *         be synchronized!
-   */
-
-  saved                    = rtems_filesystem_current;
-  rtems_filesystem_current = iop->pathinfo;
-
-  /* clone the current node */
-  if (rtems_filesystem_evaluate_path(".", 1, 0, &loc, 0)) {
-    /* cloning failed; restore original and bail out */
-    rtems_filesystem_current = saved;
-    return -1;
+  if ( rv == 0 ) {
+    rv = rtems_filesystem_chdir( &loc );
   }
-  /* release the old one */
-  rtems_filesystem_freenode( &saved );
-
-  rtems_filesystem_current = loc;
 
-  return 0;
+  return rv;
 }
diff --git a/cpukit/libcsupport/src/fchmod.c b/cpukit/libcsupport/src/fchmod.c
index e90a155bdb..e651066a77 100644
--- a/cpukit/libcsupport/src/fchmod.c
+++ b/cpukit/libcsupport/src/fchmod.c
@@ -12,31 +12,25 @@
  */
 
 #if HAVE_CONFIG_H
-#include "config.h"
+  #include "config.h"
 #endif
 
-#include <unistd.h>
 #include <sys/stat.h>
-#include <errno.h>
 
-#include <rtems.h>
-#include <rtems/libio.h>
 #include <rtems/libio_.h>
-#include <rtems/seterr.h>
 
-int fchmod(
-  int       fd,
-  mode_t    mode
-)
+int fchmod( int fd, mode_t mode )
 {
+  int rv;
   rtems_libio_t *iop;
 
   rtems_libio_check_fd( fd );
   iop = rtems_libio_iop( fd );
   rtems_libio_check_is_open(iop);
 
-  /*
-   *  Now process the fchmod().
-   */
-  return (*iop->pathinfo.handlers->fchmod_h)( &iop->pathinfo, mode );
+  rtems_filesystem_instance_lock( &iop->pathinfo );
+  rv = (*iop->pathinfo.ops->fchmod_h)( &iop->pathinfo, mode );
+  rtems_filesystem_instance_unlock( &iop->pathinfo );
+
+  return rv;
 }
diff --git a/cpukit/libcsupport/src/fchown.c b/cpukit/libcsupport/src/fchown.c
index 13bb2b9da0..b5891bf36d 100644
--- a/cpukit/libcsupport/src/fchown.c
+++ b/cpukit/libcsupport/src/fchown.c
@@ -12,24 +12,16 @@
  */
 
 #if HAVE_CONFIG_H
-#include "config.h"
+  #include "config.h"
 #endif
 
-#include <sys/stat.h>
-#include <errno.h>
-
-#include <rtems.h>
-#include <rtems/libio.h>
+#include <unistd.h>
 
 #include <rtems/libio_.h>
-#include <rtems/seterr.h>
 
-int fchown(
-  int   fd,
-  uid_t owner,
-  gid_t group
-)
+int fchown( int fd, uid_t owner, gid_t group )
 {
+  int rv = 0;
   rtems_libio_t *iop;
 
   rtems_libio_check_fd( fd );
@@ -38,5 +30,9 @@ int fchown(
 
   rtems_libio_check_permissions( iop, LIBIO_FLAGS_WRITE );
 
-  return (*iop->pathinfo.ops->chown_h)( &iop->pathinfo, owner, group );
+  rtems_filesystem_instance_lock( &iop->pathinfo );
+  rv = (*iop->pathinfo.ops->chown_h)( &iop->pathinfo, owner, group );
+  rtems_filesystem_instance_unlock( &iop->pathinfo );
+
+  return rv;
 }
diff --git a/cpukit/libcsupport/src/fcntl.c b/cpukit/libcsupport/src/fcntl.c
index 988a9414ee..10f783b910 100644
--- a/cpukit/libcsupport/src/fcntl.c
+++ b/cpukit/libcsupport/src/fcntl.c
@@ -12,17 +12,53 @@
  */
 
 #if HAVE_CONFIG_H
-#include "config.h"
+  #include "config.h"
 #endif
 
 #include <stdarg.h>
 #include <unistd.h>
 #include <fcntl.h>
-#include <errno.h>
 
-#include <rtems.h>
 #include <rtems/libio_.h>
 
+static int duplicate_iop( rtems_libio_t *iop, int fd2 )
+{
+  int rv = 0;
+
+  /*
+   * FIXME: We ignore the start value fd2 for the file descriptor search.  This
+   * is not POSIX conform.
+   */
+  rtems_libio_t *diop = rtems_libio_allocate();
+
+  if (diop != NULL) {
+    int oflag = rtems_libio_to_fcntl_flags( iop->flags );
+
+    oflag &= ~O_CREAT;
+    diop->flags |= rtems_libio_fcntl_flags( oflag );
+
+    rtems_filesystem_instance_lock( &iop->pathinfo );
+    rtems_filesystem_location_clone( &diop->pathinfo, &iop->pathinfo );
+    rtems_filesystem_instance_unlock( &iop->pathinfo );
+
+    /*
+     * XXX: We call the open handler here to have a proper open and close pair.
+     *
+     * FIXME: What to do with the path?
+     */
+    rv = (*diop->pathinfo.handlers->open_h)( diop, NULL, oflag, 0 );
+    if ( rv == 0 ) {
+      rv = diop - rtems_libio_iops;
+    } else {
+      rtems_libio_free( diop );
+    }
+  } else {
+    rv = -1;
+  }
+
+  return rv;
+}
+
 static int vfcntl(
   int fd,
   int cmd,
@@ -30,7 +66,6 @@ static int vfcntl(
 )
 {
   rtems_libio_t *iop;
-  rtems_libio_t *diop;
   int            fd2;
   int            flags;
   int            mask;
@@ -51,20 +86,7 @@ static int vfcntl(
   switch ( cmd ) {
     case F_DUPFD:        /* dup */
       fd2 = va_arg( ap, int );
-      if ( fd2 )
-        diop = rtems_libio_iop( fd2 );
-      else {
-        /* allocate a file control block */
-        diop = rtems_libio_allocate();
-        if ( diop == 0 ) {
-          ret = -1;
-          break;
-        }
-      }
-
-      diop->flags      = iop->flags;
-      diop->pathinfo   = iop->pathinfo;
-      ret = (int) (diop - rtems_libio_iops);
+      ret = duplicate_iop( iop, fd2 );
       break;
 
     case F_GETFD:        /* get f_flags */
@@ -138,7 +160,7 @@ static int vfcntl(
    */
 
   if (ret >= 0) {
-    int err = (*iop->pathinfo.handlers->fcntl_h)( cmd, iop );
+    int err = (*iop->pathinfo.handlers->fcntl_h)( iop, cmd );
     if (err) {
       errno = err;
       ret = -1;
diff --git a/cpukit/libcsupport/src/freenode.c b/cpukit/libcsupport/src/freenode.c
index 21a9c1de91..cc05b6034a 100644
--- a/cpukit/libcsupport/src/freenode.c
+++ b/cpukit/libcsupport/src/freenode.c
@@ -4,6 +4,9 @@
  *  COPYRIGHT (c) 1989-2010.
  *  On-Line Applications Research Corporation (OAR).
  *
+ *  Modifications to support reference counting in the file system are
+ *  Copyright (c) 2012 embedded brains GmbH.
+ *
  *  The license and distribution terms for this file may be
  *  found in the file LICENSE in this distribution or at
  *  http://www.rtems.com/license/LICENSE.
@@ -11,10 +14,16 @@
  *  $Id$
  */
 
-#include <stdlib.h>
+#if HAVE_CONFIG_H
+  #include "config.h"
+#endif
+
 #include <rtems/libio_.h>
 
-void rtems_filesystem_freenode( rtems_filesystem_location_info_t *_node )
+void rtems_filesystem_location_free( rtems_filesystem_location_info_t *loc )
 {
-  _node->ops->freenod_h(_node );
+  rtems_filesystem_instance_lock( loc );
+  (*loc->ops->freenod_h)( loc );
+  rtems_filesystem_instance_unlock( loc );
+  rtems_filesystem_location_remove_from_mt_entry( loc );
 }
diff --git a/cpukit/libcsupport/src/ftruncate.c b/cpukit/libcsupport/src/ftruncate.c
index 9c50ca2fbe..66c1dc0cc6 100644
--- a/cpukit/libcsupport/src/ftruncate.c
+++ b/cpukit/libcsupport/src/ftruncate.c
@@ -12,39 +12,30 @@
  */
 
 #if HAVE_CONFIG_H
-#include "config.h"
+  #include "config.h"
 #endif
 
 #include <unistd.h>
-#include <errno.h>
 
 #include <rtems/libio_.h>
-#include <rtems/seterr.h>
 
-int ftruncate(
-  int     fd,
-  off_t   length
-)
+int ftruncate( int fd, off_t length )
 {
-  rtems_libio_t                    *iop;
-  rtems_filesystem_location_info_t  loc;
+  int rv = 0;
 
-  rtems_libio_check_fd( fd );
-  iop = rtems_libio_iop( fd );
-  rtems_libio_check_is_open(iop);
-  rtems_libio_check_permissions( iop, LIBIO_FLAGS_WRITE );
+  if ( length >= 0 ) {
+    rtems_libio_t *iop;
 
-  /*
-   *  Now process the ftruncate() request.
-   */
+    rtems_libio_check_fd( fd );
+    iop = rtems_libio_iop( fd );
+    rtems_libio_check_is_open( iop );
+    rtems_libio_check_permissions( iop, LIBIO_FLAGS_WRITE );
 
-  /*
-   *  Make sure we are not working on a directory
-   */
+    rv = (*iop->pathinfo.handlers->ftruncate_h)( iop, length );
+  } else {
+    errno = EINVAL;
+    rv = -1;
+  }
 
-  loc = iop->pathinfo;
-  if ( (*loc.ops->node_type_h)( &loc ) == RTEMS_FILESYSTEM_DIRECTORY )
-    rtems_set_errno_and_return_minus_one( EISDIR );
-
-  return (*iop->pathinfo.handlers->ftruncate_h)( iop, length );
+  return rv;
 }
diff --git a/cpukit/libcsupport/src/getdents.c b/cpukit/libcsupport/src/getdents.c
index d0b787cd88..82fa678978 100644
--- a/cpukit/libcsupport/src/getdents.c
+++ b/cpukit/libcsupport/src/getdents.c
@@ -32,8 +32,8 @@ int getdents(
   int   dd_len
 )
 {
-  rtems_libio_t                    *iop;
-  rtems_filesystem_location_info_t  loc;
+  rtems_libio_t *iop;
+  rtems_filesystem_node_types_t type;
 
   /*
    *  Get the file control block structure associated with the file descriptor
@@ -43,8 +43,8 @@ int getdents(
   /*
    *  Make sure we are working on a directory
    */
-  loc = iop->pathinfo;
-  if ( (*loc.ops->node_type_h)( &loc ) != RTEMS_FILESYSTEM_DIRECTORY )
+  type = rtems_filesystem_node_type( &iop->pathinfo );
+  if ( type != RTEMS_FILESYSTEM_DIRECTORY )
     rtems_set_errno_and_return_minus_one( ENOTDIR );
 
   /*
diff --git a/cpukit/libcsupport/src/lchown.c b/cpukit/libcsupport/src/lchown.c
index 1092f9017e..83bdf6f95c 100644
--- a/cpukit/libcsupport/src/lchown.c
+++ b/cpukit/libcsupport/src/lchown.c
@@ -12,20 +12,19 @@
  */
 
 #if HAVE_CONFIG_H
-#include "config.h"
+  #include "config.h"
 #endif
 
 #include <unistd.h>
 
-#include <rtems.h>
+#include <rtems/libio_.h>
 
-int _chown_helper( const char *path, uid_t owner, gid_t group, int follow_link);
-
-int lchown(
-  const char *path,
-  uid_t       owner,
-  gid_t       group
-)
+int lchown( const char *path, uid_t owner, gid_t group )
 {
-  return _chown_helper( path, owner, group, false );
+  return rtems_filesystem_chown(
+    path,
+    owner,
+    group,
+    RTEMS_LIBIO_FOLLOW_HARD_LINK
+  );
 }
diff --git a/cpukit/libcsupport/src/libio.c b/cpukit/libcsupport/src/libio.c
index d080d01596..985ad8bad9 100644
--- a/cpukit/libcsupport/src/libio.c
+++ b/cpukit/libcsupport/src/libio.c
@@ -47,14 +47,14 @@
  *  Convert UNIX fnctl(2) flags to ones that RTEMS drivers understand
  */
 
-const rtems_assoc_t access_modes_assoc[] = {
+static const rtems_assoc_t access_modes_assoc[] = {
   { "READ",       LIBIO_FLAGS_READ,  O_RDONLY },
   { "WRITE",      LIBIO_FLAGS_WRITE, O_WRONLY },
   { "READ/WRITE", LIBIO_FLAGS_READ_WRITE, O_RDWR },
   { 0, 0, 0 },
 };
 
-const rtems_assoc_t status_flags_assoc[] = {
+static const rtems_assoc_t status_flags_assoc[] = {
 #ifdef ACCEPT_O_NDELAY_ALIAS
   { "NO DELAY",  LIBIO_FLAGS_NO_DELAY,  O_NDELAY },
 #endif
@@ -64,9 +64,7 @@ const rtems_assoc_t status_flags_assoc[] = {
   { 0, 0, 0 },
 };
 
-uint32_t   rtems_libio_fcntl_flags(
-  uint32_t   fcntl_flags
-)
+uint32_t rtems_libio_fcntl_flags( int fcntl_flags )
 {
   uint32_t   flags = 0;
   uint32_t   access_modes;
@@ -75,7 +73,7 @@ uint32_t   rtems_libio_fcntl_flags(
    * Access mode is a small integer
    */
 
-  access_modes = fcntl_flags & O_ACCMODE;
+  access_modes = (uint32_t) (fcntl_flags & O_ACCMODE);
   fcntl_flags &= ~O_ACCMODE;
   flags = rtems_assoc_local_by_remote( access_modes_assoc, access_modes );
 
@@ -83,8 +81,11 @@ uint32_t   rtems_libio_fcntl_flags(
    * Everything else is single bits
    */
 
-  flags |=
-     rtems_assoc_local_by_remote_bitfield(status_flags_assoc, fcntl_flags);
+  flags |= rtems_assoc_local_by_remote_bitfield(
+    status_flags_assoc,
+    (uint32_t) fcntl_flags
+  );
+
   return flags;
 }
 
@@ -94,11 +95,9 @@ uint32_t   rtems_libio_fcntl_flags(
  *  Convert RTEMS internal flags to UNIX fnctl(2) flags
  */
 
-uint32_t   rtems_libio_to_fcntl_flags(
-  uint32_t   flags
-)
+int rtems_libio_to_fcntl_flags( uint32_t flags )
 {
-  uint32_t   fcntl_flags = 0;
+  int fcntl_flags = 0;
 
   if ( (flags & LIBIO_FLAGS_READ_WRITE) == LIBIO_FLAGS_READ_WRITE ) {
     fcntl_flags |= O_RDWR;
@@ -176,6 +175,8 @@ void rtems_libio_free(
   rtems_libio_t *iop
 )
 {
+  rtems_filesystem_location_free( &iop->pathinfo );
+
   rtems_libio_lock();
 
     if (iop->sem)
@@ -187,92 +188,3 @@ void rtems_libio_free(
 
   rtems_libio_unlock();
 }
-
-/*
- *  rtems_libio_is_open_files_in_fs
- *
- *  This routine scans the entire file descriptor table to determine if the
- *  are any active file descriptors that refer to the at least one node in the
- *  file system that we are trying to dismount.
- *
- *  If there is at least one node in the file system referenced by the mount
- *  table entry a 1 is returned, otherwise a 0 is returned.
- */
-
-int rtems_libio_is_open_files_in_fs(
-  rtems_filesystem_mount_table_entry_t * fs_mt_entry
-)
-{
-  rtems_libio_t     *iop;
-  int                result = 0;
-  uint32_t           i;
-
-  rtems_libio_lock();
-
-  /*
-   *  Look for any active file descriptor entry.
-   */
-
-  for (iop=rtems_libio_iops,i=0; i < rtems_libio_number_iops; iop++, i++){
-
-    if ((iop->flags & LIBIO_FLAGS_OPEN) != 0) {
-
-       /*
-        *  Check if this node is under the file system that we
-        *  are trying to dismount.
-        */
-
-       if ( iop->pathinfo.mt_entry == fs_mt_entry ) {
-          result = 1;
-          break;
-       }
-    }
-  }
-
-  rtems_libio_unlock();
-
-  return result;
-}
-
-/*
- *  rtems_libio_is_file_open
- *
- *  This routine scans the entire file descriptor table to determine if the
- *  given file refers to an active file descriptor.
- *
- *  If the given file is open a 1 is returned, otherwise a 0 is returned.
- */
-
-int rtems_libio_is_file_open(
-  void         *node_access
-)
-{
-  rtems_libio_t     *iop;
-  int                result=0;
-  uint32_t           i;
-
-  rtems_libio_lock();
-
-  /*
-   *  Look for any active file descriptor entry.
-   */
-
- for (iop=rtems_libio_iops,i=0; i < rtems_libio_number_iops; iop++, i++){
-    if ((iop->flags & LIBIO_FLAGS_OPEN) != 0) {
-
-       /*
-        *  Check if this node is under the file system that we
-        *  are trying to dismount.
-        */
-
-       if ( iop->pathinfo.node_access == node_access ) {
-          result = 1;
-          break;
-       }
-    }
-  }
-
-  rtems_libio_unlock();
-
-  return result;
-}
diff --git a/cpukit/libcsupport/src/libio_sockets.c b/cpukit/libcsupport/src/libio_sockets.c
index c67e19d78c..ff02e0f4ea 100644
--- a/cpukit/libcsupport/src/libio_sockets.c
+++ b/cpukit/libcsupport/src/libio_sockets.c
@@ -18,6 +18,7 @@
 
 #include <rtems/libio_.h>
 #include <rtems/seterr.h>
+#include <rtems/rtems_bsdnet_internal.h>
 
 /*
  * Convert an RTEMS file descriptor to a BSD socket pointer.
@@ -69,5 +70,7 @@ int rtems_bsdnet_makeFdForSocket(
   iop->data1 = so;
   iop->pathinfo.handlers = h;
   iop->pathinfo.ops = &rtems_filesystem_operations_default;
+  iop->pathinfo.mt_entry = &rtems_filesystem_null_mt_entry;
+  rtems_filesystem_location_add_to_mt_entry(&iop->pathinfo);
   return fd;
 }
diff --git a/cpukit/libcsupport/src/link.c b/cpukit/libcsupport/src/link.c
index 11b6521dea..cf370fb9dc 100644
--- a/cpukit/libcsupport/src/link.c
+++ b/cpukit/libcsupport/src/link.c
@@ -12,65 +12,44 @@
  */
 
 #if HAVE_CONFIG_H
-#include "config.h"
+  #include "config.h"
 #endif
 
-#include <rtems.h>
-#include <rtems/libio.h>
-#include <errno.h>
+#include <unistd.h>
 
 #include <rtems/libio_.h>
-#include <rtems/seterr.h>
 
-int link(
-  const char *existing,
-  const char *new
-)
+int link( const char *path1, const char *path2 )
 {
-  rtems_filesystem_location_info_t    existing_loc;
-  rtems_filesystem_location_info_t    parent_loc;
-  int                                 i;
-  int                                 result;
-  const char                         *name_start;
-
-  /*
-   * Get the node we are linking to.
-   */
-
-  result = rtems_filesystem_evaluate_path( existing, strlen( existing ),
-                                           0, &existing_loc, true );
-  if ( result != 0 )
-     return -1;
-
-  /*
-   * Get the parent of the node we are creating.
-   */
-
-  rtems_filesystem_get_start_loc( new, &i, &parent_loc );
-
-  result = (*parent_loc.ops->evalformake_h)( &new[i], &parent_loc, &name_start );
-  if ( result != 0 ) {
-    rtems_filesystem_freenode( &existing_loc );
-    return -1;
+  int rv = 0;
+  rtems_filesystem_eval_path_context_t ctx_1;
+  rtems_filesystem_eval_path_context_t ctx_2;
+  int eval_flags_1 = RTEMS_LIBIO_FOLLOW_LINK;
+  int eval_flags_2 = RTEMS_LIBIO_FOLLOW_LINK
+    | RTEMS_LIBIO_MAKE
+    | RTEMS_LIBIO_EXCLUSIVE;
+  const rtems_filesystem_location_info_t *currentloc_1 =
+    rtems_filesystem_eval_path_start( &ctx_1, path1, eval_flags_1 );
+  const rtems_filesystem_location_info_t *currentloc_2 =
+    rtems_filesystem_eval_path_start( &ctx_2, path2, eval_flags_2 );
+
+  rv = rtems_filesystem_location_exists_in_same_fs_instance_as(
+    currentloc_1,
+    currentloc_2
+  );
+  if ( rv == 0 ) {
+    rv = (*currentloc_2->ops->link_h)(
+      currentloc_2,
+      currentloc_1,
+      rtems_filesystem_eval_path_get_token( &ctx_2 ),
+      rtems_filesystem_eval_path_get_tokenlen( &ctx_2 )
+    );
   }
 
-  /*
-   *  Check to see if the caller is trying to link across file system
-   *  boundaries.
-   */
-
-  if ( parent_loc.mt_entry != existing_loc.mt_entry ) {
-    rtems_filesystem_freenode( &existing_loc );
-    rtems_filesystem_freenode( &parent_loc );
-    rtems_set_errno_and_return_minus_one( EXDEV );
-  }
-
-  result = (*parent_loc.ops->link_h)( &existing_loc, &parent_loc, name_start );
-
-  rtems_filesystem_freenode( &existing_loc );
-  rtems_filesystem_freenode( &parent_loc );
+  rtems_filesystem_eval_path_cleanup( &ctx_1 );
+  rtems_filesystem_eval_path_cleanup( &ctx_2 );
 
-  return result;
+  return rv;
 }
 
 /*
@@ -85,10 +64,10 @@ int link(
 
 int _link_r(
   struct _reent *ptr __attribute__((unused)),
-  const char    *existing,
-  const char    *new
+  const char    *path1,
+  const char    *path2
 )
 {
-  return link( existing, new );
+  return link( path1, path2 );
 }
 #endif
diff --git a/cpukit/libcsupport/src/lseek.c b/cpukit/libcsupport/src/lseek.c
index 3f37029807..7c1f76b36b 100644
--- a/cpukit/libcsupport/src/lseek.c
+++ b/cpukit/libcsupport/src/lseek.c
@@ -12,64 +12,74 @@
  */
 
 #if HAVE_CONFIG_H
-#include "config.h"
+  #include "config.h"
 #endif
 
-#include <stdio.h>
+#include <unistd.h>
 
 #include <rtems/libio_.h>
-#include <rtems/seterr.h>
 
-off_t lseek(
-  int     fd,
-  off_t   offset,
-  int     whence
-)
+off_t lseek( int fd, off_t offset, int whence )
 {
+  off_t rv = 0;
   rtems_libio_t *iop;
-  off_t          old_offset;
-  off_t          status;
+  off_t reference_offset;
+  off_t old_offset;
+  off_t new_offset;
 
   rtems_libio_check_fd( fd );
   iop = rtems_libio_iop( fd );
   rtems_libio_check_is_open(iop);
 
-  /*
-   *  Now process the lseek().
-   */
-
   old_offset = iop->offset;
   switch ( whence ) {
     case SEEK_SET:
-      iop->offset = offset;
+      reference_offset = 0;
       break;
-
     case SEEK_CUR:
-      iop->offset += offset;
+      reference_offset = old_offset;
       break;
-
     case SEEK_END:
-      iop->offset = iop->size + offset;
+      reference_offset = iop->size;
       break;
-
     default:
-      rtems_set_errno_and_return_minus_one( EINVAL );
+      errno = EINVAL;
+      rv = (off_t) -1;
+      break;
+  }
+  new_offset = reference_offset + offset;
+
+  if ( rv == 0 ) {
+    if (
+      (reference_offset >= 0 && new_offset >= offset)
+        || (reference_offset < 0 && new_offset <= offset)
+    ) {
+      switch ( rtems_filesystem_node_type( &iop->pathinfo ) ) {
+        case RTEMS_FILESYSTEM_DIRECTORY:
+        case RTEMS_FILESYSTEM_MEMORY_FILE:
+          if ( new_offset < 0 ) {
+            errno = EINVAL;
+            rv = (off_t) -1;
+          }
+          break;
+        default:
+          break;
+      }
+
+      if ( rv == 0 ) {
+        iop->offset = new_offset;
+        rv = (*iop->pathinfo.handlers->lseek_h)( iop, offset, whence );
+        if ( rv == (off_t) -1 ) {
+          iop->offset = old_offset;
+        }
+      }
+    } else {
+      errno = EOVERFLOW;
+      rv = (off_t) -1;
+    }
   }
 
-  /*
-   *  At this time, handlers assume iop->offset has the desired
-   *  new offset.
-   */
-
-  status = (*iop->pathinfo.handlers->lseek_h)( iop, offset, whence );
-  if ( status == (off_t) -1 )
-    iop->offset = old_offset;
-
-  /*
-   *  So if the operation failed, we have to restore iop->offset.
-   */
-
-  return status;
+  return rv;
 }
 
 /*
diff --git a/cpukit/libcsupport/src/lstat.c b/cpukit/libcsupport/src/lstat.c
index f034f4aa76..d35713eb04 100644
--- a/cpukit/libcsupport/src/lstat.c
+++ b/cpukit/libcsupport/src/lstat.c
@@ -17,6 +17,6 @@
 
 #define _STAT_NAME         lstat
 #define _STAT_R_NAME       _lstat_r
-#define _STAT_FOLLOW_LINKS false
+#define _STAT_FOLLOW_LINKS RTEMS_LIBIO_FOLLOW_HARD_LINK
 
 #include "stat.c"
diff --git a/cpukit/libcsupport/src/mknod.c b/cpukit/libcsupport/src/mknod.c
index 29aff43c31..dae2b3bf98 100644
--- a/cpukit/libcsupport/src/mknod.c
+++ b/cpukit/libcsupport/src/mknod.c
@@ -16,58 +16,65 @@
  */
 
 #if HAVE_CONFIG_H
-#include "config.h"
+  #include "config.h"
 #endif
 
-#include <sys/types.h>
 #include <sys/stat.h>
-#include <fcntl.h>
-#include <unistd.h>
-#include <errno.h>
-#include <stdlib.h>
 
 #include <rtems/libio_.h>
-#include <rtems/seterr.h>
 
-int mknod(
-  const char *pathname,
-  mode_t      mode,
-  dev_t       dev
+int rtems_filesystem_mknod(
+  const rtems_filesystem_location_info_t *parentloc,
+  const char *name,
+  size_t namelen,
+  mode_t mode,
+  dev_t dev
 )
 {
-  rtems_filesystem_location_info_t    temp_loc;
-  int                                 i;
-  const char                         *name_start;
-  int                                 result;
+  int rv = 0;
 
-  /*
-   * The file type is field within the mode. Check we have a sane mode set.
-   */
-  switch (mode & S_IFMT)
-  {
-    case S_IFDIR:
-    case S_IFCHR:
+  mode &= ~rtems_filesystem_umask;
+
+  switch (mode & S_IFMT) {
     case S_IFBLK:
-    case S_IFREG:
+    case S_IFCHR:
+    case S_IFDIR:
     case S_IFIFO:
+    case S_IFREG:
       break;
     default:
-      rtems_set_errno_and_return_minus_one( EINVAL );
+      errno = EINVAL;
+      rv = -1;
+      break;
   }
   
-  rtems_filesystem_get_start_loc( pathname, &i, &temp_loc );
+  if ( rv == 0 ) {
+    rv = (*parentloc->ops->mknod_h)( parentloc, name, namelen, mode, dev );
+  }
 
-  result = (*temp_loc.ops->evalformake_h)(
-    &pathname[i],
-    &temp_loc,
-    &name_start
-  );
-  if ( result != 0 )
-    return -1;
+  return rv;
+}
 
-  result =  (*temp_loc.ops->mknod_h)( name_start, mode, dev, &temp_loc );
+int mknod( const char *path, mode_t mode, dev_t dev )
+{
+  int rv = 0;
+  rtems_filesystem_eval_path_context_t ctx;
+  int eval_flags = RTEMS_LIBIO_FOLLOW_LINK
+    | RTEMS_LIBIO_MAKE
+    | RTEMS_LIBIO_EXCLUSIVE
+    | (S_ISDIR(mode) ? RTEMS_LIBIO_ACCEPT_RESIDUAL_DELIMITERS : 0);
+  const rtems_filesystem_location_info_t *currentloc =
+    rtems_filesystem_eval_path_start( &ctx, path, eval_flags );
+
+  rv = rtems_filesystem_mknod(
+    currentloc,
+    rtems_filesystem_eval_path_get_token( &ctx ),
+    rtems_filesystem_eval_path_get_tokenlen( &ctx ),
+    mode,
+    dev
+  );
 
-  rtems_filesystem_freenode( &temp_loc );
+  rtems_filesystem_eval_path_cleanup( &ctx );
 
-  return result;
+  return rv;
 }
diff --git a/cpukit/libcsupport/src/mount.c b/cpukit/libcsupport/src/mount.c
index 00a07aab3a..47c08f7dba 100644
--- a/cpukit/libcsupport/src/mount.c
+++ b/cpukit/libcsupport/src/mount.c
@@ -20,22 +20,15 @@
  */
 
 #if HAVE_CONFIG_H
-#include "config.h"
+  #include "config.h"
 #endif
 
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <rtems/chain.h>
-#include <rtems/seterr.h>
-#include <fcntl.h>
-#include <unistd.h>
-#include <errno.h>
 #include <stdlib.h>
 #include <string.h>
 
 #include <rtems/libio_.h>
 
-static RTEMS_CHAIN_DEFINE_EMPTY(mount_chain);
+RTEMS_CHAIN_DEFINE_EMPTY(rtems_filesystem_mount_table);
 
 /*
  * Default pathconfs.
@@ -55,14 +48,6 @@ const rtems_filesystem_limits_and_options_t rtems_filesystem_default_pathconf =
    0     /* posix_vdisable: special char processing, 0=no, 1=yes */
 };
 
-static bool is_node_fs_root(
-  const rtems_filesystem_mount_table_entry_t *mt_entry,
-  void *arg
-)
-{
-  return arg == mt_entry->mt_fs_root.node_access;
-}
-
 static rtems_filesystem_mount_table_entry_t *alloc_mount_table_entry(
   const char *source_or_null,
   const char *target_or_null,
@@ -76,11 +61,15 @@ static rtems_filesystem_mount_table_entry_t *alloc_mount_table_entry(
     strlen( source_or_null ) + 1 : 0;
   size_t target_size = strlen( target ) + 1;
   size_t size = sizeof( rtems_filesystem_mount_table_entry_t )
-    + filesystemtype_size + source_size + target_size;
+    + filesystemtype_size + source_size + target_size
+    + sizeof( rtems_filesystem_global_location_t );
   rtems_filesystem_mount_table_entry_t *mt_entry = calloc( 1, size );
 
   if ( mt_entry != NULL ) {
-    char *str = (char *) mt_entry + sizeof( *mt_entry );
+    rtems_filesystem_global_location_t *mt_fs_root =
+      (rtems_filesystem_global_location_t *)
+        ((char *) mt_entry + sizeof( *mt_entry ));
+    char *str = (char *) mt_fs_root + sizeof( *mt_fs_root );
 
     memcpy( str, filesystemtype, filesystemtype_size );
     mt_entry->type = str;
@@ -92,6 +81,23 @@ static rtems_filesystem_mount_table_entry_t *alloc_mount_table_entry(
 
     memcpy( str, target, target_size );
     mt_entry->target = str;
+    str += target_size;
+
+    mt_entry->mounted = true;
+    mt_entry->mt_fs_root = mt_fs_root;
+    mt_entry->pathconf_limits_and_options = rtems_filesystem_default_pathconf;
+
+    mt_fs_root->location.mt_entry = mt_entry;
+    mt_fs_root->reference_count = 1;
+
+    rtems_chain_initialize(
+      &mt_entry->location_chain,
+      mt_fs_root,
+      1,
+      sizeof(*mt_fs_root)
+    );
+  } else {
+    free( mt_entry );
   }
 
   *target_length_ptr = target_size - 1;
@@ -99,184 +105,140 @@ static rtems_filesystem_mount_table_entry_t *alloc_mount_table_entry(
   return mt_entry;
 }
 
-/*
- *  mount
- *
- *  This routine will attempt to mount a new file system at the specified
- *  mount point. A series of tests will be run to determine if any of the
- *  following reasons exist to prevent the mount operation:
- *
- * 	1) The file system type or options are not valid
- *	2) No new file system root node is specified
- * 	3) The selected file system has already been mounted
- * 	4) The mount point exists with the proper permissions to allow mounting
- *	5) The selected mount point already has a file system mounted to it
- *
- */
-
-int mount(
-  const char                 *source,
-  const char                 *target,
-  const char                 *filesystemtype,
-  rtems_filesystem_options_t options,
-  const void                 *data
+static int register_subordinate_file_system(
+  rtems_filesystem_mount_table_entry_t *mt_entry,
+  const char *target
 )
 {
-  rtems_filesystem_fsmount_me_t mount_h = NULL;
-  rtems_filesystem_location_info_t      loc;
-  rtems_filesystem_mount_table_entry_t *mt_entry = NULL;
-  rtems_filesystem_location_info_t     *loc_to_free = NULL;
-  bool has_target = target != NULL;
-  size_t target_length = 0;
-
-  /*
-   *  Are the file system options valid?
-   */
-
-  if ( options != RTEMS_FILESYSTEM_READ_ONLY &&
-       options != RTEMS_FILESYSTEM_READ_WRITE )
-    rtems_set_errno_and_return_minus_one( EINVAL );
-
-  /*
-   *  Get mount handler
-   */
-  mount_h = rtems_filesystem_get_mount_handler( filesystemtype );
-  if ( !mount_h )
-    rtems_set_errno_and_return_minus_one( EINVAL );
-
-  /*
-   * Allocate a mount table entry
-   */
-  mt_entry = alloc_mount_table_entry(
-    source,
-    target,
-    filesystemtype,
-    &target_length
-  );
-  if ( !mt_entry )
-    rtems_set_errno_and_return_minus_one( ENOMEM );
-
-  mt_entry->mt_fs_root.mt_entry = mt_entry;
-  mt_entry->options = options;
-  mt_entry->pathconf_limits_and_options = rtems_filesystem_default_pathconf;
-
-  /*
-   *  The mount_point should be a directory with read/write/execute
-   *  permissions in the existing tree.
-   */
-
-  if ( has_target ) {
-    if ( rtems_filesystem_evaluate_path(
-           target, target_length, RTEMS_LIBIO_PERMS_RWX, &loc, true ) == -1 )
-      goto cleanup_and_bail;
-
-    loc_to_free = &loc;
-
-    /*
-     *  Test to see if it is a directory
-     */
-
-    if ( loc.ops->node_type_h( &loc ) != RTEMS_FILESYSTEM_DIRECTORY ) {
-      errno = ENOTDIR;
-      goto cleanup_and_bail;
+  int rv = 0;
+  rtems_filesystem_eval_path_context_t ctx;
+  int eval_flags = RTEMS_LIBIO_PERMS_RWX
+    | RTEMS_LIBIO_FOLLOW_LINK;
+  rtems_filesystem_location_info_t *currentloc =
+    rtems_filesystem_eval_path_start( &ctx, target, eval_flags );
+
+  if ( !rtems_filesystem_location_is_root( currentloc ) ) {
+    rtems_filesystem_location_info_t targetloc;
+    rtems_filesystem_global_location_t *mt_point_node;
+
+    rtems_filesystem_eval_path_extract_currentloc( &ctx, &targetloc );
+    mt_point_node = rtems_filesystem_location_transform_to_global( &targetloc );
+    mt_entry->mt_point_node = mt_point_node;
+    rv = (*mt_point_node->location.ops->mount_h)( mt_entry );
+    if ( rv == 0 ) {
+      rtems_filesystem_mt_lock();
+      rtems_chain_append_unprotected(
+        &rtems_filesystem_mount_table,
+        &mt_entry->mt_node
+      );
+      rtems_filesystem_mt_unlock();
+    } else {
+      rtems_filesystem_global_location_release( mt_point_node );
     }
+  } else {
+    rtems_filesystem_eval_path_error( &ctx, EBUSY );
+    rv = -1;
+  }
 
-    /*
-     *  You can only mount one file system onto a single mount point.
-     */
+  rtems_filesystem_eval_path_cleanup( &ctx );
 
-    if ( rtems_filesystem_mount_iterate( is_node_fs_root, loc.node_access ) ) {
-      errno = EBUSY;
-      goto cleanup_and_bail;
-    }
+  return rv;
+}
 
-    /*
-     *  This must be a good mount point, so move the location information
-     *  into the allocated mount entry.  Note:  the information that
-     *  may have been allocated in loc should not be sent to freenode
-     *  until the system is unmounted.  It may be needed to correctly
-     *  traverse the tree.
-     */
-
-    mt_entry->mt_point_node.node_access = loc.node_access;
-    mt_entry->mt_point_node.handlers = loc.handlers;
-    mt_entry->mt_point_node.ops = loc.ops;
-    mt_entry->mt_point_node.mt_entry = loc.mt_entry;
-
-    /*
-     *  This link to the parent is only done when we are dealing with system
-     *  below the base file system
-     */
-
-    if ( loc.ops->mount_h( mt_entry ) ) {
-      goto cleanup_and_bail;
-    }
+static int register_root_file_system(
+  rtems_filesystem_mount_table_entry_t *mt_entry
+)
+{
+  int rv = 0;
+
+  rtems_filesystem_mt_lock();
+  if ( rtems_chain_is_empty( &rtems_filesystem_mount_table ) ) {
+    rtems_chain_append_unprotected(
+      &rtems_filesystem_mount_table,
+      &mt_entry->mt_node
+    );
   } else {
-    /*
-     * Do we already have a base file system ?
-     */
-    if ( !rtems_chain_is_empty( &mount_chain ) ) {
-      errno = EINVAL;
-      goto cleanup_and_bail;
-    }
-
-    /*
-     *  This is a mount of the base file system --> The
-     *  mt_point_node.node_access will be left to null to indicate that this
-     *  is the root of the entire file system.
-     */
+    errno = EINVAL;
+    rv = -1;
   }
-
-  if ( (*mount_h)( mt_entry, data ) ) {
-    /*
-     * Try to undo the mount operation
-     */
-    loc.ops->unmount_h( mt_entry );
-    goto cleanup_and_bail;
+  rtems_filesystem_mt_unlock();
+
+  if ( rv == 0 ) {
+    rtems_filesystem_global_location_t *new_fs_root =
+      rtems_filesystem_global_location_obtain( &mt_entry->mt_fs_root );
+    rtems_filesystem_global_location_t *new_fs_current =
+      rtems_filesystem_global_location_obtain( &mt_entry->mt_fs_root );
+
+    rtems_filesystem_global_location_assign(
+      &rtems_filesystem_root,
+      new_fs_root
+    );
+    rtems_filesystem_global_location_assign(
+      &rtems_filesystem_current,
+      new_fs_current
+    );
   }
 
-  /*
-   *  Add the mount table entry to the mount table chain
-   */
-  rtems_libio_lock();
-  rtems_chain_append( &mount_chain, &mt_entry->Node );
-  rtems_libio_unlock();
-
-  if ( !has_target )
-    rtems_filesystem_root = mt_entry->mt_fs_root;
-
-  return 0;
-
-cleanup_and_bail:
-
-  free( mt_entry );
-
-  if ( loc_to_free )
-    rtems_filesystem_freenode( loc_to_free );
-
-  return -1;
+  return rv;
 }
 
-bool rtems_filesystem_mount_iterate(
-  rtems_per_filesystem_mount_routine routine,
-  void *routine_arg
+int mount(
+  const char                 *source,
+  const char                 *target,
+  const char                 *filesystemtype,
+  rtems_filesystem_options_t options,
+  const void                 *data
 )
 {
-  rtems_chain_node *node = NULL;
-  bool stop = false;
-
-  rtems_libio_lock();
-  for (
-    node = rtems_chain_first( &mount_chain );
-    !rtems_chain_is_tail( &mount_chain, node ) && !stop;
-    node = rtems_chain_next( node )
-  ) {
-    const rtems_filesystem_mount_table_entry_t *mt_entry =
-      (rtems_filesystem_mount_table_entry_t *) node;
+  int rv = 0;
 
-    stop = (*routine)( mt_entry, routine_arg );
+  if (
+    options == RTEMS_FILESYSTEM_READ_ONLY
+      || options == RTEMS_FILESYSTEM_READ_WRITE
+  ) {
+    rtems_filesystem_fsmount_me_t fsmount_me_h =
+      rtems_filesystem_get_mount_handler( filesystemtype );
+
+    if ( fsmount_me_h != NULL ) {
+      size_t target_length = 0;
+      rtems_filesystem_mount_table_entry_t *mt_entry = alloc_mount_table_entry(
+        source,
+        target,
+        filesystemtype,
+        &target_length
+      );
+
+      if ( mt_entry != NULL ) {
+        mt_entry->writeable = options == RTEMS_FILESYSTEM_READ_WRITE;
+
+        rv = (*fsmount_me_h)( mt_entry, data );
+        if ( rv == 0 ) {
+          if ( target != NULL ) {
+            rv = register_subordinate_file_system( mt_entry, target );
+          } else {
+            rv = register_root_file_system( mt_entry );
+          }
+
+          if ( rv != 0 ) {
+            (*mt_entry->mt_fs_root->location.ops->fsunmount_me_h)( mt_entry );
+          }
+        }
+
+        if ( rv != 0 ) {
+          free( mt_entry );
+        }
+      } else {
+        errno = ENOMEM;
+        rv = -1;
+      }
+    } else {
+      errno = EINVAL;
+      rv = -1;
+    }
+  } else {
+    errno = EINVAL;
+    rv = -1;
   }
-  rtems_libio_unlock();
 
-  return stop;
+  return rv;
 }
diff --git a/cpukit/libcsupport/src/open.c b/cpukit/libcsupport/src/open.c
index a2e1b507e3..6fa7783322 100644
--- a/cpukit/libcsupport/src/open.c
+++ b/cpukit/libcsupport/src/open.c
@@ -4,6 +4,9 @@
  *  COPYRIGHT (c) 1989-2010.
  *  On-Line Applications Research Corporation (OAR).
  *
+ *  Modifications to support reference counting in the file system are
+ *  Copyright (c) 2012 embedded brains GmbH.
+ *
  *  The license and distribution terms for this file may be
  *  found in the file LICENSE in this distribution or at
  *  http://www.rtems.com/license/LICENSE.
@@ -12,185 +15,135 @@
  */
 
 #if HAVE_CONFIG_H
-#include "config.h"
+  #include "config.h"
 #endif
 
-#include <stdarg.h>
+#include <sys/stat.h>
 #include <fcntl.h>
-#include <rtems/libio_.h>
-#include <rtems/seterr.h>
-
+#include <stdarg.h>
 #include <unistd.h>
 
-/*
- *  Returns file descriptor on success or -1 and errno set to one of the
- *  following:
- *
- *    EACCESS  - Seach permission is denied on a component of the path prefix,
- *               or the file exists and the permissions specified by the
- *               flags are denied, or the file does not exist and write
- *               permission is denied for the parent directory of the file
- *               to be created, or O_TRUNC is specified and write permission
- *               is denied.
- *    EEXIST   - O_CREAT and O_EXCL are set and the named file exists.
- *    EINTR    - The open( operation was interrupted by a signal.
- *    EINVAL   - This implementation does not support synchronized IO for this
- *               file.
- *    EISDIR   - The named file is a directory and the flags argument
- *               specified write or read/write access.
- *    EMFILE   - Too many file descriptors are in used by this process.
- *    ENAMETOOLONG -
- *               The length of the path exceeds PATH_MAX or a pathname
- *               component is longer than NAME_MAX while POSIX_NO_TRUNC
- *               is in effect.
- *    ENFILE   - Too many files are open in the system.
- *    ENOENT   - O_CREAT is not set and and the anmed file does not exist,
- *               or O_CREAT is set and either the path prefix does not exist
- *               or the path argument points to an empty string.
- *    ENOSPC   - The directory or file system that would contain the new file
- *               cannot be extended.
- *    ENOTDIR  - A component of the path prefix is not a directory.
- *    ENXIO    - O_NONBLOCK is set, the named file is a FIFO, O_WRONLY is
- *               set, and no process has the file open for reading.
- *    EROFS    - The named file resides on a read-only file system and either
- *               O_WRONLY, O_RDWR, O_CREAT (if the file does not exist), or
- *               O_TRUNC is set in the flags argument.
- */
+#include <rtems/libio_.h>
 
-int open(
-  const char   *pathname,
-  int           flags,
-  ...
+static void create_regular_file(
+  rtems_filesystem_eval_path_context_t *ctx,
+  mode_t mode
 )
 {
-  va_list                             ap;
-  mode_t                              mode;
-  int                                 rc;
-  rtems_libio_t                      *iop = 0;
-  int                                 status;
-  rtems_filesystem_location_info_t    loc;
-  rtems_filesystem_location_info_t   *loc_to_free = NULL;
-  int                                 eval_flags;
-
-  /*
-   * Set the Evaluation flags
-   */
-  eval_flags = 0;
-  status = flags + 1;
-  if ( ( status & _FREAD ) == _FREAD )
-    eval_flags |= RTEMS_LIBIO_PERMS_READ;
-  if ( ( status & _FWRITE ) == _FWRITE )
-    eval_flags |= RTEMS_LIBIO_PERMS_WRITE;
-
-  va_start(ap, flags);
-
-  mode = va_arg( ap, mode_t );
+  int rv = 0;
+  const rtems_filesystem_location_info_t *currentloc = 
+    rtems_filesystem_eval_path_get_currentloc( ctx );
+  const char *token = rtems_filesystem_eval_path_get_token( ctx );
+  size_t tokenlen = rtems_filesystem_eval_path_get_tokenlen( ctx );
+
+  rv = rtems_filesystem_mknod(
+    currentloc,
+    token,
+    tokenlen,
+    S_IFREG | mode,
+    0
+  );
+
+  if ( rv == 0 ) {
+    /* The mode only applies to future accesses of the newly created file */
+    rtems_filesystem_eval_path_set_flags( ctx, 0 );
+
+    rtems_filesystem_eval_path_set_path( ctx, token, tokenlen );
+    rtems_filesystem_eval_path_continue( ctx );
+  } else {
+    rtems_filesystem_eval_path_error( ctx, 0 );
+  }
+}
 
-  /*
-   * NOTE: This comment is OBSOLETE.  The proper way to do this now
-   *       would be to support a magic mounted file system.
-   *
-   *             Additional external I/O handlers would be supported by adding
-   *             code to pick apart the pathname appropriately. The networking
-   *             code does not require changes here since network file
-   *             descriptors are obtained using socket(), not open().
-   */
-
-  /* allocate a file control block */
-  iop = rtems_libio_allocate();
-  if ( iop == 0 ) {
-    rc = ENFILE;
-    goto done;
+static int do_open(
+  rtems_libio_t *iop,
+  const char *path,
+  int oflag,
+  mode_t mode
+)
+{
+  int rv = 0;
+  int fd = iop - rtems_libio_iops;
+  int rwflag = oflag + 1;
+  bool read_access = (rwflag & _FREAD) == _FREAD;
+  bool write_access = (rwflag & _FWRITE) == _FWRITE;
+  bool make = (oflag & O_CREAT) == O_CREAT;
+  bool exclusive = (oflag & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL);
+  bool truncate = (oflag & O_TRUNC) == O_TRUNC;
+  int eval_flags = RTEMS_LIBIO_FOLLOW_LINK
+    | (read_access ? RTEMS_LIBIO_PERMS_READ : 0)
+    | (write_access ? RTEMS_LIBIO_PERMS_WRITE : 0)
+    | (make ? RTEMS_LIBIO_MAKE : 0)
+    | (exclusive ?  RTEMS_LIBIO_EXCLUSIVE : 0);
+  rtems_filesystem_eval_path_context_t ctx;
+
+  rtems_filesystem_eval_path_start( &ctx, path, eval_flags );
+
+  if ( rtems_filesystem_eval_path_has_token( &ctx ) ) {
+    create_regular_file( &ctx, mode );
   }
 
-  /*
-   *  See if the file exists.
-   */
-  status = rtems_filesystem_evaluate_path(
-    pathname, strlen( pathname ), eval_flags, &loc, true );
+  if ( write_access ) {
+    const rtems_filesystem_location_info_t *currentloc =
+      rtems_filesystem_eval_path_get_currentloc( &ctx );
+    rtems_filesystem_node_types_t type =
+      (*currentloc->ops->node_type_h)( currentloc );
 
-  if ( status == -1 ) {
-    if ( errno != ENOENT ) {
-      rc = errno;
-      goto done;
+    if ( type == RTEMS_FILESYSTEM_DIRECTORY ) {
+      rtems_filesystem_eval_path_error( &ctx, EISDIR );
     }
+  }
 
-    /* If the file does not exist and we are not trying to create it--> error */
-    if ( !(flags & O_CREAT) ) {
-      rc = ENOENT;
-      goto done;
-    }
+  iop->flags |= rtems_libio_fcntl_flags( oflag );
+  rtems_filesystem_eval_path_extract_currentloc( &ctx, &iop->pathinfo );
+  rtems_filesystem_eval_path_cleanup( &ctx );
 
-    /* Create the node for the new regular file */
-    rc = mknod( pathname, S_IFREG | mode, 0LL );
-    if ( rc ) {
-      rc = errno;
-      goto done;
+  rv = (*iop->pathinfo.handlers->open_h)( iop, path, oflag, mode );
+
+  if ( rv == 0 ) {
+    if ( truncate ) {
+      rv = ftruncate( fd, 0 );
+      if ( rv != 0 ) {
+        (*iop->pathinfo.handlers->close_h)( iop );
+      }
     }
 
-    /*
-     * After we do the mknod(), we have to evaluate the path to get the
-     * "loc" structure needed to actually have the file itself open.
-     * So we created it, and then we need to have "look it up."
-     */
-    status = rtems_filesystem_evaluate_path(
-      pathname, strlen( pathname ), 0x0, &loc, true );
-    if ( status != 0 ) {   /* The file did not exist */
-      rc = EACCES;
-      goto done;
+    if ( rv == 0 ) {
+      rv = fd;
+    } else {
+      rv = -1;
     }
+  }
 
-  } else if ((flags & (O_EXCL|O_CREAT)) == (O_EXCL|O_CREAT)) {
-    /* We were trying to create a file that already exists */
-    rc = EEXIST;
-    loc_to_free = &loc;
-    goto done;
+  if ( rv < 0 ) {
+    rtems_libio_free( iop );
   }
 
-  loc_to_free = &loc;
+  return rv;
+}
+
+int open( const char *path, int oflag, ... )
+{
+  int rv = 0;
+  va_list ap;
+  mode_t mode = 0;
+  rtems_libio_t *iop = NULL;
 
-  /*
-   *  Fill in the file control block based on the loc structure
-   *  returned by successful path evaluation.
-   */
-  iop->flags     |= rtems_libio_fcntl_flags( flags );
-  iop->pathinfo   = loc;
+  va_start( ap, oflag );
 
-  rc = (*iop->pathinfo.handlers->open_h)( iop, pathname, flags, mode );
-  if ( rc ) {
-    rc = errno;
-    goto done;
-  }
+  mode = va_arg( ap, mode_t );
 
-  /*
-   *  Optionally truncate the file.
-   */
-  if ( (flags & O_TRUNC) == O_TRUNC ) {
-    rc = ftruncate( iop - rtems_libio_iops, 0 );
-    if ( rc ) {
-      if(errno) rc = errno;
-      close( iop - rtems_libio_iops );
-      /* those are released by close(): */
-      iop = 0;
-      loc_to_free = NULL;
-    }
+  iop = rtems_libio_allocate();
+  if ( iop != NULL ) {
+    rv = do_open( iop, path, oflag, mode );
+  } else {
+    errno = ENFILE;
+    rv = -1;
   }
 
-  /*
-   *  Single exit and clean up path.
-   */
-done:
-  va_end(ap);
-
-  if ( rc ) {
-    if ( iop )
-      rtems_libio_free( iop );
-    if ( loc_to_free )
-      rtems_filesystem_freenode( loc_to_free );
-    rtems_set_errno_and_return_minus_one( rc );
-  }
+  va_end( ap );
 
-  return iop - rtems_libio_iops;
+  return rv;
 }
 
 /*
@@ -206,10 +159,10 @@ done:
 int _open_r(
   struct _reent *ptr __attribute__((unused)),
   const char    *buf,
-  int            flags,
+  int            oflag,
   int            mode
 )
 {
-  return open( buf, flags, mode );
+  return open( buf, oflag, mode );
 }
 #endif
diff --git a/cpukit/libcsupport/src/privateenv.c b/cpukit/libcsupport/src/privateenv.c
index 89137200b7..28f866272b 100644
--- a/cpukit/libcsupport/src/privateenv.c
+++ b/cpukit/libcsupport/src/privateenv.c
@@ -1,3 +1,9 @@
+/**
+ * @file
+ *
+ * @ingroup LibIOEnv
+ */
+
 /*
  *  Instantiate a private user environment for the calling thread.
  *
@@ -14,191 +20,148 @@
  */
 
 #if HAVE_CONFIG_H
-#include "config.h"
+  #include "config.h"
 #endif
 
-#include <stdlib.h> /* free */
+#define __RTEMS_VIOLATE_KERNEL_VISIBILITY__
+
+#include <stdlib.h>
 
-#include <rtems.h>
-#include <rtems/chain.h>
 #include <rtems/libio_.h>
+#include <rtems/score/thread.h>
 
-/* cleanup a user environment
- * NOTE: this must be called with
- *       thread dispatching disabled!
- */
-static void
-free_user_env(void *venv)
+static void free_user_env(void *arg)
 {
-  rtems_user_env_t *env = (rtems_user_env_t*) venv ;
-
-  if (env != &rtems_global_user_env
-  #ifdef HAVE_USERENV_REFCNT
-      && --env->refcnt <= 0
-  #endif
-  ) {
-    rtems_filesystem_freenode( &env->current_directory);
-    rtems_filesystem_freenode( &env->root_directory);
-    free(env);
+  rtems_user_env_t *env = arg;
+  bool uses_global_env = env == &rtems_global_user_env;
+
+  if (!uses_global_env) {
+    if (env->reference_count == 1) {
+      rtems_filesystem_global_location_release(env->current_directory);
+      rtems_filesystem_global_location_release(env->root_directory);
+      free(env);
+    } else {
+      --env->reference_count;
+    }
   }
 }
 
+static void free_user_env_protected(rtems_user_env_t *env)
+{
+  _Thread_Disable_dispatch();
+  free_user_env(env);
+  _Thread_Enable_dispatch();
+}
+
 rtems_status_code rtems_libio_set_private_env(void)
 {
   rtems_status_code sc = RTEMS_SUCCESSFUL;
-  rtems_id task_id = rtems_task_self();
-  rtems_filesystem_location_info_t root_loc;
-  rtems_filesystem_location_info_t current_loc;
-  rtems_user_env_t *new_env = NULL;
-  int rv = 0;
-
-  rv = rtems_filesystem_evaluate_path("/", 1, 0, &root_loc, 0);
-  if (rv != 0)
-    goto error_0;
-
-  rv = rtems_filesystem_evaluate_path("/", 1, 0, &current_loc, 0);
-  if (rv != 0)
-    goto error_1;
-
-  /* 
-   * Malloc is necessary whenever the current task does not
-   * have its own environment in place. This could be:
-   * a) it never had one
-   * OR
-   * b) it shared another task's environment
-   */
-
-  /* 
-   * Bharath: I'm not sure if the check can be reduced to
-   * if( rtems_current_user_env->task_id != task_id ) {
-   */
-
-  if (
-    rtems_current_user_env == &rtems_global_user_env
-      || rtems_current_user_env->task_id != task_id
-  ) {
-    new_env = malloc(sizeof(rtems_user_env_t));
-    if (new_env == NULL)
-      goto error_2;
-
-    #ifdef HAVE_USERENV_REFCNT
-      new_env->refcnt = 1;
-    #endif
-
-    sc = rtems_task_variable_add(
-      RTEMS_SELF,
-      (void*)&rtems_current_user_env,
-      (void(*)(void *))free_user_env
-    );
-    if (sc != RTEMS_SUCCESSFUL)
-      goto error_3;
-
-    rtems_current_user_env = new_env;
+  rtems_id self_task_id = rtems_task_self();
+  rtems_user_env_t *old_env = rtems_current_user_env;
+  bool uses_global_env = old_env == &rtems_global_user_env;
+  bool uses_shared_env = old_env->task_id != self_task_id;
+
+  if (uses_global_env || uses_shared_env) {
+    rtems_user_env_t *new_env = calloc(1, sizeof(*new_env));
+
+    if (new_env != NULL) {
+      *new_env = *old_env;
+      new_env->reference_count = 1;
+      new_env->task_id = self_task_id;
+      new_env->root_directory =
+        rtems_filesystem_global_location_obtain(&old_env->root_directory);
+      new_env->current_directory =
+        rtems_filesystem_global_location_obtain(&old_env->current_directory);
+
+      if (
+        !rtems_filesystem_global_location_is_null(new_env->root_directory)
+          && !rtems_filesystem_global_location_is_null(new_env->current_directory)
+      ) {
+        sc = rtems_task_variable_add(
+          RTEMS_SELF,
+          (void **) &rtems_current_user_env,
+          free_user_env
+        );
+        if (sc == RTEMS_SUCCESSFUL) {
+          free_user_env_protected(old_env);
+          rtems_current_user_env = new_env;
+        } else {
+          sc = RTEMS_TOO_MANY;
+        }
+      } else {
+        sc = RTEMS_UNSATISFIED;
+      }
+
+      if (sc != RTEMS_SUCCESSFUL) {
+        free_user_env(new_env);
+      }
+    } else {
+      sc = RTEMS_NO_MEMORY;
+    }
   }
 
-  /* Inherit the global values */
-  *rtems_current_user_env = rtems_global_user_env;
-
-  rtems_current_user_env->task_id = task_id;
-
-  /*
-   * Clone the pathlocs. In contrast to most other code we must _not_ free the
-   * original locs because what we are trying to do here is forking off clones.
-   * The reason is a pathloc can be allocated by the file system and needs to
-   * be freed when deleting the environment.
-   */
-  rtems_filesystem_root = root_loc;
-  rtems_filesystem_current = current_loc;
-
-  return RTEMS_SUCCESSFUL;
-
-error_3:
-  free(new_env);
-
-error_2:
-  rtems_filesystem_freenode(&current_loc);
-
-error_1:
-  rtems_filesystem_freenode(&root_loc);
-
-error_0:
-  return RTEMS_NO_MEMORY;
+  return sc;
 }
 
-/*
- *  Share the same private environment between two tasks:
- *      Task_id (remote) and RTEMS_SELF(current).
- */
-
-/* NOTE:
- *
- * THIS CODE HAS NO PROTECTION IMPLEMENTED
- *
- * Tasks who wish to share their environments must
- *
- *  a) assert that no participants are concurrently
- *     executing
- *     libio_share_private_env() and/or libio_set_private_env()
- *
- *  b) mutex access to rtems_filesystem_current, rtems_filesytem_root
- *     while changing any of those (chdir(), chroot()).
- */
-
 rtems_status_code rtems_libio_share_private_env(rtems_id task_id)
 {
-  rtems_status_code  sc;
-  rtems_user_env_t * shared_user_env;
-  rtems_id           current_task_id;
-
-  /* 
-   * get current task id 
-   */
-  current_task_id = rtems_task_self();
-
-  /*
-   * If this was an attempt to share the task with self,
-   * if somebody wanted to do it... Lets tell them, its shared
-   */
-
-  if( task_id == current_task_id )
-    return RTEMS_SUCCESSFUL;
-  /* 
-   * Try to get the requested user environment 
-   */
-  sc = rtems_task_variable_get(
-	 task_id,
-	 (void*)&rtems_current_user_env, 
-	 (void*)&shared_user_env );
-
-  /* 
-   * If it was not successful, return the error code 
-   */
-    if (sc != RTEMS_SUCCESSFUL)
-      return sc;
-
-    /* 
-     * If we are here, we have the required environment to be
-     * shared with the current task
-    */
+  rtems_status_code sc = RTEMS_SUCCESSFUL;
+  rtems_id self_task_id = rtems_task_self();
+
+  if (task_id != RTEMS_SELF && self_task_id != task_id) {
+    rtems_user_env_t *env;
 
     /*
-     * If we have a current environment in place, we need to 
-     * free it, since we will be sharing the variable with the
-     * shared_user_env
+     * We have to disable the thread dispatching to prevent deletion of the
+     * environment in the meantime.
      */
-
-  if (rtems_current_user_env->task_id==current_task_id) {
-    rtems_user_env_t  *tmp = rtems_current_user_env;
-    free_user_env( tmp );
+    _Thread_Disable_dispatch();
+    sc = rtems_task_variable_get(
+      task_id,
+      (void *) &rtems_current_user_env, 
+      (void *) &env
+    );
+    if (sc == RTEMS_SUCCESSFUL) {
+      ++env->reference_count;
+    } else {
+      sc = RTEMS_UNSATISFIED;
+    }
+    _Thread_Enable_dispatch();
+
+    if (sc == RTEMS_SUCCESSFUL) {
+      sc = rtems_task_variable_add(
+        RTEMS_SELF,
+        (void **) &rtems_current_user_env,
+        free_user_env
+      );
+      if (sc == RTEMS_SUCCESSFUL) {
+        free_user_env_protected(rtems_current_user_env);
+        rtems_current_user_env = env;
+      } else {
+        free_user_env_protected(env);
+        sc = RTEMS_TOO_MANY;
+      }
+    }
   }
 
-  /* the current_user_env is the same pointer that remote env */
-  rtems_current_user_env = shared_user_env;
+  return sc;
+}
 
-  /* increase the reference count */
-#ifdef HAVE_USERENV_REFCNT
-  rtems_current_user_env->refcnt++;
-#endif
+void rtems_libio_use_global_env(void)
+{
+  rtems_status_code sc = RTEMS_SUCCESSFUL;
+  rtems_user_env_t *env = rtems_current_user_env;
+  bool uses_private_env = env != &rtems_global_user_env;
 
-  return RTEMS_SUCCESSFUL;
+  if (uses_private_env) {
+    sc = rtems_task_variable_delete(
+      RTEMS_SELF,
+      (void **) &rtems_current_user_env
+    );
+    if (sc != RTEMS_SUCCESSFUL) {
+      rtems_fatal_error_occurred(0xdeadbeef);
+    }
+
+    rtems_current_user_env = &rtems_global_user_env;
+  }
 }
diff --git a/cpukit/libcsupport/src/readlink.c b/cpukit/libcsupport/src/readlink.c
index 1880ed667e..e2c88e866c 100644
--- a/cpukit/libcsupport/src/readlink.c
+++ b/cpukit/libcsupport/src/readlink.c
@@ -12,37 +12,31 @@
  */
 
 #if HAVE_CONFIG_H
-#include "config.h"
+  #include "config.h"
 #endif
 
+#include <unistd.h>
+
 #include <rtems/libio_.h>
-#include <rtems/seterr.h>
 
-ssize_t readlink(
-  const char *pathname,
-  char       *buf,
-  size_t      bufsize
-)
+ssize_t readlink( const char *path, char *buf, size_t bufsize )
 {
-  rtems_filesystem_location_info_t  loc;
-  int                               result;
-
-  if (!buf)
-    rtems_set_errno_and_return_minus_one( EFAULT );
-
-  result = rtems_filesystem_evaluate_path( pathname, strlen( pathname ),
-                                           0, &loc, false );
-  if ( result != 0 )
-     return -1;
-
-  if (  (*loc.ops->node_type_h)( &loc ) != RTEMS_FILESYSTEM_SYM_LINK ){
-    rtems_filesystem_freenode( &loc );
-    rtems_set_errno_and_return_minus_one( EINVAL );
+  ssize_t rv = 0;
+  rtems_filesystem_eval_path_context_t ctx;
+  int eval_flags = RTEMS_LIBIO_FOLLOW_HARD_LINK;
+  const rtems_filesystem_location_info_t *currentloc =
+    rtems_filesystem_eval_path_start( &ctx, path, eval_flags );
+  rtems_filesystem_node_types_t type =
+    (*currentloc->ops->node_type_h)( currentloc );
+
+  if ( type == RTEMS_FILESYSTEM_SYM_LINK ) {
+    rv = (*currentloc->ops->readlink_h)( currentloc, buf, bufsize );
+  } else {
+    rtems_filesystem_eval_path_error( &ctx, EINVAL );
+    rv = -1;
   }
 
-  result =  (*loc.ops->readlink_h)( &loc, buf, bufsize );
-
-  rtems_filesystem_freenode( &loc );
+  rtems_filesystem_eval_path_cleanup( &ctx );
 
-  return result;
+  return rv;
 }
diff --git a/cpukit/libcsupport/src/rmdir.c b/cpukit/libcsupport/src/rmdir.c
index d7d4edf675..07ecbb3a0d 100644
--- a/cpukit/libcsupport/src/rmdir.c
+++ b/cpukit/libcsupport/src/rmdir.c
@@ -12,84 +12,44 @@
  */
 
 #if HAVE_CONFIG_H
-#include "config.h"
+  #include "config.h"
 #endif
 
-#include <sys/types.h>
-#include <fcntl.h>
 #include <unistd.h>
-#include <errno.h>
-#include <stdlib.h>
 
 #include <rtems/libio_.h>
-#include <rtems/seterr.h>
 
-int rmdir(
-  const char *pathname
-)
+int rmdir( const char *path )
 {
-  int                               parentpathlen;
-  const char                       *name;
-  rtems_filesystem_location_info_t  parentloc;
-  rtems_filesystem_location_info_t  loc;
-  int                               i;
-  int                               result;
-  bool                              free_parentloc = false;
-
-  /*
-   *  Get the parent node of the node we wish to remove. Find the parent path.
-   */
-
-  parentpathlen = rtems_filesystem_dirname ( pathname );
-
-  if ( parentpathlen == 0 )
-    rtems_filesystem_get_start_loc( pathname, &i, &parentloc );
-  else {
-    result = rtems_filesystem_evaluate_path(pathname, parentpathlen,
-                                            RTEMS_LIBIO_PERMS_WRITE,
-                                            &parentloc,
-                                            false );
-    if ( result != 0 )
-      return -1;
-
-    free_parentloc = true;
-  }
-
-  /*
-   * Start from the parent to find the node that should be under it.
-   */
-
-  loc = parentloc;
-  name = pathname + parentpathlen;
-  name += rtems_filesystem_prefix_separators( name, strlen( name ) );
-
-  result = rtems_filesystem_evaluate_relative_path( name , strlen( name ),
-                                                    0, &loc, false );
-  if ( result != 0 ) {
-    if ( free_parentloc )
-      rtems_filesystem_freenode( &parentloc );
-    return -1;
-  }
-
-  /*
-   * Verify you can remove this node as a directory.
-   */
-  if ( (*loc.ops->node_type_h)( &loc ) != RTEMS_FILESYSTEM_DIRECTORY ) {
-    rtems_filesystem_freenode( &loc );
-    if ( free_parentloc )
-      rtems_filesystem_freenode( &parentloc );
-    rtems_set_errno_and_return_minus_one( ENOTDIR );
+  int rv = 0;
+  rtems_filesystem_eval_path_context_t ctx;
+  int eval_flags = RTEMS_LIBIO_REJECT_TERMINAL_DOT;
+  rtems_filesystem_location_info_t parentloc;
+  int parent_eval_flags = RTEMS_LIBIO_PERMS_WRITE
+    | RTEMS_LIBIO_PERMS_SEARCH
+    | RTEMS_LIBIO_FOLLOW_LINK;
+  const rtems_filesystem_location_info_t *currentloc =
+    rtems_filesystem_eval_path_start_with_parent(
+      &ctx,
+      path,
+      eval_flags,
+      &parentloc,
+      parent_eval_flags
+    );
+  rtems_filesystem_node_types_t type =
+    (*currentloc->ops->node_type_h)( currentloc );
+
+  if ( type == RTEMS_FILESYSTEM_DIRECTORY ) {
+    rv = (*currentloc->ops->rmnod_h)(
+      &parentloc,
+      currentloc
+    );
+  } else {
+    rtems_filesystem_eval_path_error( &ctx, ENOTDIR );
+    rv = -1;
   }
 
-  /*
-   * Use the filesystems rmnod to remove the node.
-   */
-
-  result =  (*loc.handlers->rmnod_h)( &parentloc, &loc );
-
-  rtems_filesystem_freenode( &loc );
-  if ( free_parentloc )
-    rtems_filesystem_freenode( &parentloc );
+  rtems_filesystem_eval_path_cleanup_with_parent( &ctx, &parentloc );
 
-  return result;
+  return rv;
 }
diff --git a/cpukit/libcsupport/src/stat.c b/cpukit/libcsupport/src/stat.c
index 9f06deaa52..af56fd87be 100644
--- a/cpukit/libcsupport/src/stat.c
+++ b/cpukit/libcsupport/src/stat.c
@@ -14,7 +14,7 @@
  */
 
 #if HAVE_CONFIG_H
-#include "config.h"
+  #include "config.h"
 #endif
 
 /*
@@ -25,55 +25,29 @@
 #ifndef _STAT_NAME
 #define _STAT_NAME         stat
 #define _STAT_R_NAME       _stat_r
-#define _STAT_FOLLOW_LINKS true
+#define _STAT_FOLLOW_LINKS RTEMS_LIBIO_FOLLOW_LINK
 #endif
 
-
-#include <rtems.h>
-
-#include <rtems/libio.h>
-#include <sys/types.h>
 #include <sys/stat.h>
-#include <unistd.h>
-#include <fcntl.h>
-#include <errno.h>
 #include <string.h>
 
 #include <rtems/libio_.h>
-#include <rtems/seterr.h>
 
-int _STAT_NAME(
-  const char  *path,
-  struct stat *buf
-)
+int _STAT_NAME( const char *path, struct stat *buf )
 {
-  int                              status;
-  rtems_filesystem_location_info_t loc;
-
-  /*
-   *  Check to see if we were passed a valid pointer.
-   */
-
-  if ( !buf )
-    rtems_set_errno_and_return_minus_one( EFAULT );
-
-  status = rtems_filesystem_evaluate_path( path, strlen( path ),
-                                           0, &loc, _STAT_FOLLOW_LINKS );
-  if ( status != 0 )
-    return -1;
-
-  /*
-   *  Zero out the stat structure so the various support
-   *  versions of stat don't have to.
-   */
+  int rv = 0;
+  rtems_filesystem_eval_path_context_t ctx;
+  int eval_flags = _STAT_FOLLOW_LINKS;
+  const rtems_filesystem_location_info_t *currentloc =
+    rtems_filesystem_eval_path_start( &ctx, path, eval_flags );
 
-  memset( buf, 0, sizeof(struct stat) );
+  memset( buf, 0, sizeof( *buf ) );
 
-  status =  (*loc.handlers->fstat_h)( &loc, buf );
+  rv = (*currentloc->handlers->fstat_h)( currentloc, buf );
 
-  rtems_filesystem_freenode( &loc );
+  rtems_filesystem_eval_path_cleanup( &ctx );
 
-  return status;
+  return rv;
 }
 
 /*
diff --git a/cpukit/libcsupport/src/statvfs.c b/cpukit/libcsupport/src/statvfs.c
index 599aa7edc1..61d6d8e271 100644
--- a/cpukit/libcsupport/src/statvfs.c
+++ b/cpukit/libcsupport/src/statvfs.c
@@ -13,40 +13,27 @@
  */
 
 #if HAVE_CONFIG_H
-#include "config.h"
+  #include "config.h"
 #endif
 
-#include <rtems/libio_.h>
-#include <rtems/seterr.h>
-
 #include <sys/statvfs.h>
+#include <string.h>
 
-int
-statvfs (const char *path, struct statvfs *sb)
-{
-  rtems_filesystem_location_info_t      loc;
-  rtems_filesystem_location_info_t     *fs_mount_root;
-  rtems_filesystem_mount_table_entry_t *mt_entry;
-  int                                   result;
-
-  /*
-   *  Get
-   *    The root node of the mounted filesytem.
-   *    The node for the directory that the fileystem is mounted on.
-   *    The mount entry that is being refered to.
-   */
-
-  if ( rtems_filesystem_evaluate_path( path, strlen( path ), 0x0, &loc, true ) )
-    return -1;
+#include <rtems/libio_.h>
 
-  mt_entry      = loc.mt_entry;
-  fs_mount_root = &mt_entry->mt_fs_root;
+int statvfs( const char *path, struct statvfs *buf )
+{
+  int rv = 0;
+  rtems_filesystem_eval_path_context_t ctx;
+  int eval_flags = RTEMS_LIBIO_FOLLOW_LINK;
+  const rtems_filesystem_location_info_t *currentloc =
+    rtems_filesystem_eval_path_start( &ctx, path, eval_flags );
 
-  memset (sb, 0, sizeof (struct statvfs));
+  memset( buf, 0, sizeof( *buf ) );
 
-  result = ( fs_mount_root->ops->statvfs_h )( fs_mount_root, sb );
+  rv = (*currentloc->ops->statvfs_h)( currentloc, buf );
 
-  rtems_filesystem_freenode( &loc );
+  rtems_filesystem_eval_path_cleanup( &ctx );
 
-  return result;
+  return rv;
 }
diff --git a/cpukit/libcsupport/src/sup_fs_check_permissions.c b/cpukit/libcsupport/src/sup_fs_check_permissions.c
new file mode 100644
index 0000000000..8dcecb6119
--- /dev/null
+++ b/cpukit/libcsupport/src/sup_fs_check_permissions.c
@@ -0,0 +1,66 @@
+/*
+ * Copyright (c) 2012 embedded brains GmbH.  All rights reserved.
+ *
+ *  embedded brains GmbH
+ *  Obere Lagerstr. 30
+ *  82178 Puchheim
+ *  Germany
+ *  <rtems@embedded-brains.de>
+ *
+ * The license and distribution terms for this file may be
+ * found in the file LICENSE in this distribution or at
+ * http://www.rtems.com/license/LICENSE.
+ */
+
+#if HAVE_CONFIG_H
+  #include "config.h"
+#endif
+
+#include <rtems/libio_.h>
+
+bool rtems_filesystem_check_access(
+  int eval_flags,
+  mode_t node_mode,
+  uid_t node_uid,
+  gid_t node_gid
+)
+{
+  mode_t perm_flags = eval_flags & RTEMS_LIBIO_PERMS_RWX;
+  uid_t task_uid = geteuid();
+
+  if (task_uid == 0 || task_uid == node_uid) {
+    perm_flags <<= 6;
+  } else {
+    gid_t task_gid = getegid();
+
+    if (task_gid == 0 || task_gid == node_gid) {
+      perm_flags <<= 3;
+    } else {
+      perm_flags <<= 0;
+    }
+  }
+
+  return (perm_flags & node_mode) == perm_flags;
+}
+
+bool rtems_filesystem_eval_path_check_access(
+  rtems_filesystem_eval_path_context_t *ctx,
+  int eval_flags,
+  mode_t node_mode,
+  uid_t node_uid,
+  gid_t node_gid
+)
+{
+  bool access_ok = rtems_filesystem_check_access(
+    eval_flags,
+    node_mode,
+    node_uid,
+    node_gid
+  );
+
+  if (!access_ok) {
+    rtems_filesystem_eval_path_error(ctx, EACCES);
+  }
+
+  return access_ok;
+}
diff --git a/cpukit/libcsupport/src/sup_fs_eval_path.c b/cpukit/libcsupport/src/sup_fs_eval_path.c
new file mode 100644
index 0000000000..1940cce745
--- /dev/null
+++ b/cpukit/libcsupport/src/sup_fs_eval_path.c
@@ -0,0 +1,333 @@
+/*
+ * Copyright (c) 2012 embedded brains GmbH.  All rights reserved.
+ *
+ *  embedded brains GmbH
+ *  Obere Lagerstr. 30
+ *  82178 Puchheim
+ *  Germany
+ *  <rtems@embedded-brains.de>
+ *
+ * The license and distribution terms for this file may be
+ * found in the file LICENSE in this distribution or at
+ * http://www.rtems.com/license/LICENSE.
+ */
+
+#if HAVE_CONFIG_H
+  #include "config.h"
+#endif
+
+#include <rtems/libio_.h>
+
+static size_t get_parentpathlen(const char *path, size_t pathlen)
+{
+  while (pathlen > 0) {
+    size_t i = pathlen - 1;
+
+    if (rtems_filesystem_is_delimiter(path [i])) {
+      return pathlen;
+    }
+
+    pathlen = i;
+  }
+
+  return 0;
+}
+
+static void set_startloc(
+  rtems_filesystem_eval_path_context_t *ctx,
+  rtems_filesystem_global_location_t *const *global_root_ptr,
+  rtems_filesystem_global_location_t *const *global_current_ptr
+)
+{
+  if (ctx->pathlen > 0) {
+    char c = ctx->path [0];
+
+    ctx->rootloc = rtems_filesystem_global_location_obtain(global_root_ptr);
+
+    if (rtems_filesystem_is_delimiter(c)) {
+      ++ctx->path;
+      --ctx->pathlen;
+      ctx->startloc = rtems_filesystem_global_location_obtain(
+        &ctx->rootloc
+      );
+    } else {
+      ctx->startloc = rtems_filesystem_global_location_obtain(
+        global_current_ptr
+      );
+    }
+  } else {
+    ctx->rootloc = rtems_filesystem_global_location_obtain_null();
+    ctx->startloc = rtems_filesystem_global_location_obtain_null();
+    errno = ENOENT;
+  }
+}
+
+static void check_access(
+  rtems_filesystem_eval_path_context_t *ctx,
+  int eval_flags
+)
+{
+  const rtems_filesystem_location_info_t *currentloc = &ctx->currentloc;
+  struct stat st;
+  int rv;
+
+  st.st_mode = 0;
+  st.st_uid = 0;
+  st.st_gid = 0;
+  rv = (*currentloc->handlers->fstat_h)(currentloc, &st);
+  if (rv == 0) {
+    bool access_ok = rtems_filesystem_check_access(
+      eval_flags,
+      st.st_mode,
+      st.st_uid,
+      st.st_gid
+    );
+
+    if (!access_ok) {
+      rtems_filesystem_eval_path_error(ctx, EACCES);
+    }
+  } else {
+    rtems_filesystem_eval_path_error(ctx, 0);
+  }
+}
+
+void rtems_filesystem_eval_path_continue(
+  rtems_filesystem_eval_path_context_t *ctx
+)
+{
+  int eval_flags;
+
+  while (ctx->pathlen > 0) {
+    (*ctx->currentloc.ops->eval_path_h)(ctx);
+  }
+
+  eval_flags = rtems_filesystem_eval_path_get_flags(ctx);
+  if (rtems_filesystem_eval_path_has_token(ctx)) {
+    bool make = (eval_flags & RTEMS_LIBIO_MAKE) != 0;
+
+    if (make) {
+      check_access(ctx, RTEMS_LIBIO_PERMS_WRITE);
+    } else {
+      rtems_filesystem_eval_path_error(ctx, ENOENT);
+    }
+  } else {
+    bool exclusive = (eval_flags & RTEMS_LIBIO_EXCLUSIVE) != 0;
+
+    if (!exclusive) {
+      check_access(ctx, ctx->flags);
+    } else {
+      rtems_filesystem_eval_path_error(ctx, EEXIST);
+    }
+  }
+}
+
+static rtems_filesystem_location_info_t *
+eval_path_start(
+  rtems_filesystem_eval_path_context_t *ctx,
+  const char *path,
+  size_t pathlen,
+  int eval_flags,
+  rtems_filesystem_global_location_t *const *global_root_ptr,
+  rtems_filesystem_global_location_t *const *global_current_ptr
+)
+{
+  memset(ctx, 0, sizeof(*ctx));
+
+  ctx->path = path;
+  ctx->pathlen = pathlen;
+  ctx->flags = eval_flags;
+
+  set_startloc(ctx, global_root_ptr, global_current_ptr);
+
+  rtems_filesystem_instance_lock(&ctx->startloc->location);
+
+  rtems_filesystem_location_clone(
+    &ctx->currentloc,
+    &ctx->startloc->location
+  );
+
+  rtems_filesystem_eval_path_continue(ctx);
+
+  return &ctx->currentloc;
+}
+
+rtems_filesystem_location_info_t *
+rtems_filesystem_eval_path_start_with_root_and_current(
+  rtems_filesystem_eval_path_context_t *ctx,
+  const char *path,
+  int eval_flags,
+  rtems_filesystem_global_location_t *const *global_root_ptr,
+  rtems_filesystem_global_location_t *const *global_current_ptr
+)
+{
+  return eval_path_start(
+    ctx,
+    path,
+    strlen(path),
+    eval_flags,
+    global_root_ptr,
+    global_current_ptr
+  );
+}
+
+rtems_filesystem_location_info_t *
+rtems_filesystem_eval_path_start(
+  rtems_filesystem_eval_path_context_t *ctx,
+  const char *path,
+  int eval_flags
+)
+{
+  return rtems_filesystem_eval_path_start_with_root_and_current(
+    ctx,
+    path,
+    eval_flags,
+    &rtems_filesystem_root,
+    &rtems_filesystem_current
+  );
+}
+
+rtems_filesystem_location_info_t *
+rtems_filesystem_eval_path_start_with_parent(
+  rtems_filesystem_eval_path_context_t *ctx,
+  const char *path,
+  int eval_flags,
+  rtems_filesystem_location_info_t *parentloc,
+  int parent_eval_flags
+)
+{
+  size_t pathlen = strlen(path);
+  const char *parentpath = path;
+  size_t parentpathlen = get_parentpathlen(path, pathlen);
+  const char *name = NULL;
+  size_t namelen = 0;
+  const rtems_filesystem_location_info_t *currentloc = NULL;
+
+  if (pathlen > 0) {
+    if (parentpathlen == 0) {
+      parentpath = ".";
+      parentpathlen = 1;
+      name = path;
+      namelen = pathlen;
+    } else {
+      name = path + parentpathlen;
+      namelen = pathlen - parentpathlen;
+    }
+  }
+
+  currentloc = eval_path_start(
+    ctx,
+    parentpath,
+    parentpathlen,
+    parent_eval_flags,
+    &rtems_filesystem_root,
+    &rtems_filesystem_current
+  );
+
+  rtems_filesystem_location_clone(parentloc, currentloc);
+
+  ctx->path = name;
+  ctx->pathlen = namelen;
+  ctx->flags = eval_flags;
+
+  rtems_filesystem_eval_path_continue(ctx);
+
+  return &ctx->currentloc;
+}
+
+void rtems_filesystem_eval_path_recursive(
+  rtems_filesystem_eval_path_context_t *ctx,
+  const char *path,
+  size_t pathlen
+)
+{
+  if (pathlen > 0) {
+    if (ctx->recursionlevel < RTEMS_FILESYSTEM_SYMLOOP_MAX) {
+      const char *saved_path = ctx->path;
+      size_t saved_pathlen = ctx->pathlen;
+
+      if (rtems_filesystem_is_delimiter(path [0])) {
+        rtems_filesystem_eval_path_restart(ctx, &ctx->rootloc);
+      }
+
+      ctx->path = path;
+      ctx->pathlen = pathlen;
+
+      ++ctx->recursionlevel;
+      while (ctx->pathlen > 0) {
+        (*ctx->currentloc.ops->eval_path_h)(ctx);
+      }
+      --ctx->recursionlevel;
+
+      ctx->path = saved_path;
+      ctx->pathlen = saved_pathlen;
+    } else {
+      rtems_filesystem_eval_path_error(ctx, ELOOP);
+    }
+  } else {
+    rtems_filesystem_eval_path_error(ctx, ENOENT);
+  }
+}
+
+void rtems_filesystem_eval_path_error(
+  rtems_filesystem_eval_path_context_t *ctx,
+  int eno
+)
+{
+  ctx->path = NULL;
+  ctx->pathlen = 0;
+  ctx->token = NULL;
+  ctx->tokenlen = 0;
+
+  if (!rtems_filesystem_location_is_null(&ctx->currentloc)) {
+    if (eno != 0) {
+      errno = eno;
+    }
+
+    rtems_filesystem_location_detach(&ctx->currentloc);
+  }
+}
+
+static void free_location(rtems_filesystem_location_info_t *loc)
+{
+  rtems_filesystem_mt_entry_declare_lock_context(lock_context);
+
+  (*loc->ops->freenod_h)(loc);
+
+  rtems_filesystem_mt_entry_lock(lock_context);
+  rtems_chain_extract_unprotected(&loc->mt_entry_node);
+  rtems_filesystem_mt_entry_unlock(lock_context);
+}
+
+void rtems_filesystem_eval_path_cleanup(
+  rtems_filesystem_eval_path_context_t *ctx
+)
+{
+  free_location(&ctx->currentloc);
+  rtems_filesystem_instance_unlock(&ctx->startloc->location);
+  rtems_filesystem_global_location_release(ctx->startloc);
+  rtems_filesystem_global_location_release(ctx->rootloc);
+}
+
+void rtems_filesystem_eval_path_cleanup_with_parent(
+  rtems_filesystem_eval_path_context_t *ctx,
+  rtems_filesystem_location_info_t *parentloc
+)
+{
+  free_location(parentloc);
+  rtems_filesystem_eval_path_cleanup(ctx);
+}
+
+void rtems_filesystem_eval_path_restart(
+  rtems_filesystem_eval_path_context_t *ctx,
+  rtems_filesystem_global_location_t **newstartloc_ptr
+)
+{
+  free_location(&ctx->currentloc);
+  rtems_filesystem_instance_unlock(&ctx->startloc->location);
+  rtems_filesystem_global_location_assign(
+    &ctx->startloc,
+    rtems_filesystem_global_location_obtain(newstartloc_ptr)
+  );
+  rtems_filesystem_instance_lock(&ctx->startloc->location);
+  rtems_filesystem_location_clone(&ctx->currentloc, &ctx->startloc->location);
+}
diff --git a/cpukit/libcsupport/src/sup_fs_eval_path_generic.c b/cpukit/libcsupport/src/sup_fs_eval_path_generic.c
new file mode 100644
index 0000000000..c789ee4f64
--- /dev/null
+++ b/cpukit/libcsupport/src/sup_fs_eval_path_generic.c
@@ -0,0 +1,118 @@
+/*
+ * Copyright (c) 2012 embedded brains GmbH.  All rights reserved.
+ *
+ *  embedded brains GmbH
+ *  Obere Lagerstr. 30
+ *  82178 Puchheim
+ *  Germany
+ *  <rtems@embedded-brains.de>
+ *
+ * The license and distribution terms for this file may be
+ * found in the file LICENSE in this distribution or at
+ * http://www.rtems.com/license/LICENSE.
+ */
+
+#if HAVE_CONFIG_H
+  #include "config.h"
+#endif
+
+#include <rtems/libio_.h>
+
+static bool is_fs_root( const rtems_filesystem_location_info_t *loc )
+{
+  const rtems_filesystem_location_info_t *mt_fs_root =
+    &loc->mt_entry->mt_fs_root->location;
+
+  return (*loc->ops->are_nodes_equal_h)( loc, mt_fs_root );
+}
+
+static bool is_eval_path_root(
+  const rtems_filesystem_eval_path_context_t *ctx,
+  const rtems_filesystem_location_info_t *loc
+)
+{
+  const rtems_filesystem_location_info_t *rootloc = &ctx->rootloc->location;
+
+  return loc->mt_entry == rootloc->mt_entry
+    && (*loc->ops->are_nodes_equal_h)( loc, rootloc );
+}
+
+void rtems_filesystem_eval_path_generic(
+  rtems_filesystem_eval_path_context_t *ctx,
+  void *arg,
+  const rtems_filesystem_eval_path_generic_config *config
+)
+{
+  rtems_filesystem_eval_path_generic_status status =
+    RTEMS_FILESYSTEM_EVAL_PATH_GENERIC_CONTINUE;
+
+  while (status == RTEMS_FILESYSTEM_EVAL_PATH_GENERIC_CONTINUE) {
+    const char *token;
+    size_t tokenlen;
+
+    rtems_filesystem_eval_path_get_next_token(ctx, &token, &tokenlen);
+
+    if (tokenlen > 0) {
+      if ((*config->is_directory)(ctx, arg)) {
+        if (rtems_filesystem_is_current_directory(token, tokenlen)) {
+          if (rtems_filesystem_eval_path_has_path(ctx)) {
+            status = (*config->eval_token)(ctx, arg, ".", 1);
+          } else {
+            int eval_flags = rtems_filesystem_eval_path_get_flags(ctx);
+
+            if ((eval_flags & RTEMS_LIBIO_REJECT_TERMINAL_DOT) == 0) {
+              status = (*config->eval_token)(ctx, arg, ".", 1);
+            } else {
+              rtems_filesystem_eval_path_error(ctx, EINVAL);
+              status = RTEMS_FILESYSTEM_EVAL_PATH_GENERIC_DONE;
+            }
+          }
+        } else if (rtems_filesystem_is_parent_directory(token, tokenlen)) {
+          rtems_filesystem_location_info_t *currentloc =
+            rtems_filesystem_eval_path_get_currentloc( ctx );
+
+          if (is_eval_path_root(ctx, currentloc)) {
+            /* This prevents the escape from a chroot() environment */
+            status = (*config->eval_token)(ctx, arg, ".", 1);
+          } else if (is_fs_root(currentloc)) {
+            if (currentloc->mt_entry->mt_point_node != NULL) {
+              rtems_filesystem_eval_path_put_back_token(ctx);
+              rtems_filesystem_eval_path_restart(
+                ctx,
+                &currentloc->mt_entry->mt_point_node
+              );
+              status = RTEMS_FILESYSTEM_EVAL_PATH_GENERIC_DONE;
+            } else {
+              /* This is the root file system */
+              status = (*config->eval_token)(ctx, arg, ".", 1);
+            }
+          } else {
+            status = (*config->eval_token)(ctx, arg, "..", 2);
+          }
+        } else {
+          status = (*config->eval_token)(ctx, arg, token, tokenlen);
+        }
+
+        if (status == RTEMS_FILESYSTEM_EVAL_PATH_GENERIC_NO_ENTRY) {
+          if (rtems_filesystem_eval_path_has_path(ctx)) {
+            int eval_flags;
+
+            rtems_filesystem_eval_path_eat_delimiter(ctx);
+            eval_flags = rtems_filesystem_eval_path_get_flags(ctx);
+            if (
+              (eval_flags & RTEMS_LIBIO_ACCEPT_RESIDUAL_DELIMITERS) == 0
+                || rtems_filesystem_eval_path_has_path(ctx)
+            ) {
+              rtems_filesystem_eval_path_error(ctx, ENOENT);
+            }
+          }
+        }
+      } else {
+        rtems_filesystem_eval_path_error(ctx, ENOTDIR);
+        status = RTEMS_FILESYSTEM_EVAL_PATH_GENERIC_DONE;
+      }
+    } else {
+      status = RTEMS_FILESYSTEM_EVAL_PATH_GENERIC_DONE;
+    }
+  }
+}
diff --git a/cpukit/libcsupport/src/sup_fs_exist_in_same_instance.c b/cpukit/libcsupport/src/sup_fs_exist_in_same_instance.c
new file mode 100644
index 0000000000..71a4d43b7c
--- /dev/null
+++ b/cpukit/libcsupport/src/sup_fs_exist_in_same_instance.c
@@ -0,0 +1,40 @@
+/*
+ * Copyright (c) 2012 embedded brains GmbH.  All rights reserved.
+ *
+ *  embedded brains GmbH
+ *  Obere Lagerstr. 30
+ *  82178 Puchheim
+ *  Germany
+ *  <rtems@embedded-brains.de>
+ *
+ * The license and distribution terms for this file may be
+ * found in the file LICENSE in this distribution or at
+ * http://www.rtems.com/license/LICENSE.
+ */
+
+#if HAVE_CONFIG_H
+  #include "config.h"
+#endif
+
+#include <rtems/libio_.h>
+
+int rtems_filesystem_location_exists_in_same_fs_instance_as(
+  const rtems_filesystem_location_info_t *a,
+  const rtems_filesystem_location_info_t *b
+)
+{
+  int rv = -1;
+
+  if (
+    !rtems_filesystem_location_is_null( a )
+      && !rtems_filesystem_location_is_null( b )
+  ) {
+    if ( a->mt_entry == b->mt_entry ) {
+      rv = 0;
+    } else {
+      errno = EXDEV;
+    }
+  }
+
+  return rv;
+}
diff --git a/cpukit/libcsupport/src/sup_fs_get_start_loc.c b/cpukit/libcsupport/src/sup_fs_get_start_loc.c
deleted file mode 100644
index 89f7efbb0d..0000000000
--- a/cpukit/libcsupport/src/sup_fs_get_start_loc.c
+++ /dev/null
@@ -1,48 +0,0 @@
- /**
- * @file src/sup_fs_get_start_loc.c
- */
-
-/*
- *
- *  COPYRIGHT (c) 1989-1999.
- *  On-Line Applications Research Corporation (OAR).
- *
- *  The license and distribution terms for this file may be
- *  found in the file LICENSE in this distribution or at
- *  http://www.rtems.com/license/LICENSE.
- *
- *  $Id$
- */
-
-/*
- *  rtems_filesystem_get_start_loc
- *
- *  Function to determine if path is absolute or relative
- *
- *  Parameters:
- *
- *  path : IN  - path to be checked
- *  index: OUT - 0, if relative, 1 if absolute
- *  loc  : OUT - location info of root fs if absolute
- *               location info of current fs if relative
- *
- *  Returns: void
- */
-
-/* Includes */
-
-#include "rtems/libio_.h"
-
-void rtems_filesystem_get_start_loc(const char *path,
-				    int *index,
-				    rtems_filesystem_location_info_t *loc)
-{
-  if (rtems_filesystem_is_separator(path[0])) {
-    *loc = rtems_filesystem_root;
-    *index = 1;
-  }
-  else {
-    *loc = rtems_filesystem_current;
-    *index = 0;
-  }
-}
diff --git a/cpukit/libcsupport/src/sup_fs_get_sym_start_loc.c b/cpukit/libcsupport/src/sup_fs_get_sym_start_loc.c
deleted file mode 100644
index 4bcc964a46..0000000000
--- a/cpukit/libcsupport/src/sup_fs_get_sym_start_loc.c
+++ /dev/null
@@ -1,47 +0,0 @@
- /**
- * @file src/sup_fs_get_sym_start_loc.c
- */
-
-/*
- *
- *  COPYRIGHT (c) 1989-1999.
- *  On-Line Applications Research Corporation (OAR).
- *
- *  The license and distribution terms for this file may be
- *  found in the file LICENSE in this distribution or at
- *  http://www.rtems.com/license/LICENSE.
- *
- *  $Id$
- */
-
-/*
- *  rtems_filesystem_get_sym_start_loc
- *
- *  Function to determine if path is absolute or relative
- *
- *  Parameters:
- *
- *  path : IN  - path to be checked
- *  index: OUT - 0, if relative, 1 if absolute
- *  loc  : OUT - location info of root fs if absolute
- *               location info of current fs if relative
- *
- *  Returns: void
- */
-
-/* Includes */
-
-#include "rtems/libio_.h"
-  
-void rtems_filesystem_get_sym_start_loc(const char *path,
-					int *index,
-					rtems_filesystem_location_info_t *loc)
-{
-  if (rtems_filesystem_is_separator(path[0])) {
-      *loc = rtems_filesystem_root;
-      *index = 1;
-    }
-    else {
-      *index = 0;
-    }
-}
diff --git a/cpukit/libcsupport/src/sup_fs_is_separator.c b/cpukit/libcsupport/src/sup_fs_is_separator.c
deleted file mode 100644
index 2c695e0335..0000000000
--- a/cpukit/libcsupport/src/sup_fs_is_separator.c
+++ /dev/null
@@ -1,31 +0,0 @@
-/**
- * @file src/sup_fs_is_separator.c
- */
-
-/*
- *
- *  COPYRIGHT (c) 1989-1999.
- *  On-Line Applications Research Corporation (OAR).
- *
- *  The license and distribution terms for this file may be
- *  found in the file LICENSE in this distribution or at
- *  http://www.rtems.com/license/LICENSE.
- *
- *  $Id$
- */
-
-#include <rtems/libio_.h>
-
-/*
- *  rtems_filesystem_is_separator
- *
- *  Function to determine if a character is a path name separator.
- *  This was originally a macro in libio_.h
- *
- *  NOTE:  This function handles MS-DOS and UNIX style names.
- */
-
-int rtems_filesystem_is_separator(char ch)
-{
-  return ((ch == '/') || (ch == '\\') || (ch == '\0'));
-}
diff --git a/cpukit/libcsupport/src/sup_fs_location.c b/cpukit/libcsupport/src/sup_fs_location.c
new file mode 100644
index 0000000000..5234c01ddc
--- /dev/null
+++ b/cpukit/libcsupport/src/sup_fs_location.c
@@ -0,0 +1,218 @@
+/*
+ * Copyright (c) 2012 embedded brains GmbH.  All rights reserved.
+ *
+ *  embedded brains GmbH
+ *  Obere Lagerstr. 30
+ *  82178 Puchheim
+ *  Germany
+ *  <rtems@embedded-brains.de>
+ *
+ * The license and distribution terms for this file may be
+ * found in the file LICENSE in this distribution or at
+ * http://www.rtems.com/license/LICENSE.
+ */
+
+#if HAVE_CONFIG_H
+  #include "config.h"
+#endif
+
+#define __RTEMS_VIOLATE_KERNEL_VISIBILITY__
+
+#include <stdlib.h>
+
+#include <rtems/libio_.h>
+#include <rtems/score/thread.h>
+
+static rtems_filesystem_global_location_t *deferred_released_global_locations;
+
+rtems_filesystem_location_info_t *rtems_filesystem_location_copy(
+  rtems_filesystem_location_info_t *dst,
+  const rtems_filesystem_location_info_t *src
+)
+{
+  dst->node_access = src->node_access;
+  dst->node_access_2 = src->node_access_2;
+  dst->handlers = src->handlers;
+  dst->ops = src->ops;
+  dst->mt_entry = src->mt_entry;
+  rtems_filesystem_location_add_to_mt_entry(dst);
+
+  return dst;
+}
+
+void rtems_filesystem_location_detach(
+  rtems_filesystem_location_info_t *detach
+)
+{
+  rtems_filesystem_location_free(detach);
+  rtems_filesystem_location_initialize_to_null(detach);
+}
+
+void rtems_filesystem_location_copy_and_detach(
+  rtems_filesystem_location_info_t *copy,
+  rtems_filesystem_location_info_t *detach
+)
+{
+  rtems_filesystem_location_copy(copy, detach);
+  rtems_filesystem_location_remove_from_mt_entry(detach);
+  rtems_filesystem_location_initialize_to_null(detach);
+}
+
+rtems_filesystem_global_location_t *rtems_filesystem_location_transform_to_global(
+  rtems_filesystem_location_info_t *loc
+)
+{
+  rtems_filesystem_global_location_t *global_loc = malloc(sizeof(*global_loc));
+
+  if (global_loc != NULL) {
+    global_loc->reference_count = 1;
+    global_loc->deferred_released_next = NULL;
+    global_loc->deferred_released_count = 0;
+    rtems_filesystem_location_copy(&global_loc->location, loc);
+    rtems_filesystem_location_remove_from_mt_entry(loc);
+  } else {
+    rtems_filesystem_location_free(loc);
+    global_loc = rtems_filesystem_global_location_obtain_null();
+    errno = ENOMEM;
+  }
+
+  return global_loc;
+}
+
+void rtems_filesystem_global_location_assign(
+  rtems_filesystem_global_location_t **lhs_global_loc_ptr,
+  rtems_filesystem_global_location_t *rhs_global_loc
+)
+{
+  rtems_filesystem_mt_entry_declare_lock_context(lock_context);
+  rtems_filesystem_global_location_t *lhs_global_loc;
+
+  rtems_filesystem_mt_entry_lock(lock_context);
+  lhs_global_loc = *lhs_global_loc_ptr;
+  *lhs_global_loc_ptr = rhs_global_loc;
+  rtems_filesystem_mt_entry_unlock(lock_context);
+
+  rtems_filesystem_global_location_release(lhs_global_loc);
+}
+
+static void release_with_count(
+  rtems_filesystem_global_location_t *global_loc,
+  int count
+)
+{
+  rtems_filesystem_mount_table_entry_t *mt_entry =
+    global_loc->location.mt_entry;
+  rtems_filesystem_mt_entry_declare_lock_context(lock_context);
+  bool do_free;
+  bool do_unmount;
+
+  rtems_filesystem_mt_entry_lock(lock_context);
+  global_loc->reference_count -= count;
+  do_free = global_loc->reference_count == 0;
+  do_unmount = rtems_filesystem_is_ready_for_unmount(mt_entry);
+  rtems_filesystem_mt_entry_unlock(lock_context);
+
+  if (do_free) {
+    rtems_filesystem_location_free(&global_loc->location);
+    free(global_loc);
+  }
+
+  if (do_unmount) {
+    rtems_filesystem_do_unmount(mt_entry);
+  }
+}
+
+static void deferred_release(void)
+{
+  rtems_filesystem_global_location_t *current = NULL;
+
+  do {
+    int count = 0;
+
+    _Thread_Disable_dispatch();
+    current = deferred_released_global_locations;
+    if (current != NULL) {
+      deferred_released_global_locations = current->deferred_released_next;
+      count = current->deferred_released_count;
+      current->deferred_released_next = NULL;
+      current->deferred_released_count = 0;
+    }
+    _Thread_Enable_dispatch();
+
+    if (current != NULL) {
+      release_with_count(current, count);
+    }
+  } while (current != NULL);
+}
+
+rtems_filesystem_global_location_t *rtems_filesystem_global_location_obtain(
+  rtems_filesystem_global_location_t *const *global_loc_ptr
+)
+{
+  rtems_filesystem_mt_entry_declare_lock_context(lock_context);
+  rtems_filesystem_global_location_t *global_loc;
+
+  if (deferred_released_global_locations != NULL) {
+    deferred_release();
+  }
+
+  rtems_filesystem_mt_entry_lock(lock_context);
+  global_loc = *global_loc_ptr;
+  if (global_loc == NULL || !global_loc->location.mt_entry->mounted) {
+    global_loc = &rtems_filesystem_global_location_null;
+    errno = ENXIO;
+  }
+  ++global_loc->reference_count;
+  rtems_filesystem_mt_entry_unlock(lock_context);
+
+  return global_loc;
+}
+
+void rtems_filesystem_global_location_release(
+  rtems_filesystem_global_location_t *global_loc
+)
+{
+  if (!_Thread_Dispatch_in_critical_section()) {
+    release_with_count(global_loc, 1);
+  } else {
+    if (global_loc->deferred_released_count == 0) {
+      rtems_filesystem_global_location_t *head =
+        deferred_released_global_locations;
+
+      global_loc->deferred_released_count = 1;
+      global_loc->deferred_released_next = head;
+      deferred_released_global_locations = global_loc;
+    } else {
+      ++global_loc->deferred_released_count;
+    }
+  }
+}
+
+void rtems_filesystem_location_remove_from_mt_entry(
+  rtems_filesystem_location_info_t *loc
+)
+{
+  rtems_filesystem_mt_entry_declare_lock_context(lock_context);
+  bool do_unmount;
+
+  rtems_filesystem_mt_entry_lock(lock_context);
+  rtems_chain_extract_unprotected(&loc->mt_entry_node);
+  do_unmount = rtems_filesystem_is_ready_for_unmount(loc->mt_entry);
+  rtems_filesystem_mt_entry_unlock(lock_context);
+
+  if (do_unmount) {
+    rtems_filesystem_do_unmount(loc->mt_entry);
+  }
+}
+
+void rtems_filesystem_do_unmount(
+  rtems_filesystem_mount_table_entry_t *mt_entry
+)
+{
+  rtems_filesystem_mt_lock();
+  rtems_chain_extract_unprotected(&mt_entry->mt_node);
+  rtems_filesystem_mt_unlock();
+  rtems_filesystem_global_location_release(mt_entry->mt_point_node);
+  (*mt_entry->mt_fs_root->location.ops->fsunmount_me_h)(mt_entry);
+  free(mt_entry);
+}
diff --git a/cpukit/libcsupport/src/sup_fs_mount_iterate.c b/cpukit/libcsupport/src/sup_fs_mount_iterate.c
new file mode 100644
index 0000000000..88cfca828c
--- /dev/null
+++ b/cpukit/libcsupport/src/sup_fs_mount_iterate.c
@@ -0,0 +1,44 @@
+/*
+ * Copyright (c) 2012 embedded brains GmbH.  All rights reserved.
+ *
+ *  embedded brains GmbH
+ *  Obere Lagerstr. 30
+ *  82178 Puchheim
+ *  Germany
+ *  <rtems@embedded-brains.de>
+ *
+ * The license and distribution terms for this file may be
+ * found in the file LICENSE in this distribution or at
+ * http://www.rtems.com/license/LICENSE.
+ */
+
+#if HAVE_CONFIG_H
+  #include "config.h"
+#endif
+
+#include <rtems/libio_.h>
+
+bool rtems_filesystem_mount_iterate(
+  rtems_filesystem_mt_entry_visitor visitor,
+  void *visitor_arg
+)
+{
+  rtems_chain_control *chain = &rtems_filesystem_mount_table;
+  rtems_chain_node *node = NULL;
+  bool stop = false;
+
+  rtems_filesystem_mt_lock();
+  for (
+    node = rtems_chain_first( chain );
+    !rtems_chain_is_tail( chain, node ) && !stop;
+    node = rtems_chain_next( node )
+  ) {
+    const rtems_filesystem_mount_table_entry_t *mt_entry =
+      (rtems_filesystem_mount_table_entry_t *) node;
+
+    stop = (*visitor)( mt_entry, visitor_arg );
+  }
+  rtems_filesystem_mt_unlock();
+
+  return stop;
+}
diff --git a/cpukit/libcsupport/src/sup_fs_next_token.c b/cpukit/libcsupport/src/sup_fs_next_token.c
new file mode 100644
index 0000000000..451d81bbfe
--- /dev/null
+++ b/cpukit/libcsupport/src/sup_fs_next_token.c
@@ -0,0 +1,58 @@
+/*
+ * Copyright (c) 2012 embedded brains GmbH.  All rights reserved.
+ *
+ *  embedded brains GmbH
+ *  Obere Lagerstr. 30
+ *  82178 Puchheim
+ *  Germany
+ *  <rtems@embedded-brains.de>
+ *
+ * The license and distribution terms for this file may be
+ * found in the file LICENSE in this distribution or at
+ * http://www.rtems.com/license/LICENSE.
+ */
+
+#if HAVE_CONFIG_H
+  #include "config.h"
+#endif
+
+#include <rtems/libio_.h>
+
+void rtems_filesystem_eval_path_eat_delimiter(
+  rtems_filesystem_eval_path_context_t *ctx
+)
+{
+  const char *current = ctx->path;
+  const char *end = current + ctx->pathlen;
+
+  while (current != end && rtems_filesystem_is_delimiter(*current)) {
+    ++current;
+  }
+
+  ctx->path = current;
+  ctx->pathlen = (size_t) (end - current);
+}
+
+static void next_token(rtems_filesystem_eval_path_context_t *ctx)
+{
+  const char *begin = ctx->path;
+  const char *end = begin + ctx->pathlen;
+  const char *current = begin;
+
+  while (current != end && !rtems_filesystem_is_delimiter(*current)) {
+    ++current;
+  }
+
+  ctx->path = current;
+  ctx->pathlen = (size_t) (end - current);
+  ctx->token = begin;
+  ctx->tokenlen = (size_t) (current - begin);
+}
+
+void rtems_filesystem_eval_path_next_token(
+  rtems_filesystem_eval_path_context_t *ctx
+)
+{
+  rtems_filesystem_eval_path_eat_delimiter(ctx);
+  next_token(ctx);
+}
diff --git a/cpukit/libcsupport/src/sup_fs_node_type.c b/cpukit/libcsupport/src/sup_fs_node_type.c
new file mode 100644
index 0000000000..f78451dee1
--- /dev/null
+++ b/cpukit/libcsupport/src/sup_fs_node_type.c
@@ -0,0 +1,32 @@
+/*
+ * Copyright (c) 2012 embedded brains GmbH.  All rights reserved.
+ *
+ *  embedded brains GmbH
+ *  Obere Lagerstr. 30
+ *  82178 Puchheim
+ *  Germany
+ *  <rtems@embedded-brains.de>
+ *
+ * The license and distribution terms for this file may be
+ * found in the file LICENSE in this distribution or at
+ * http://www.rtems.com/license/LICENSE.
+ */
+
+#if HAVE_CONFIG_H
+  #include "config.h"
+#endif
+
+#include <rtems/libio_.h>
+
+rtems_filesystem_node_types_t rtems_filesystem_node_type(
+  const rtems_filesystem_location_info_t *loc
+)
+{
+  rtems_filesystem_node_types_t type;
+
+  rtems_filesystem_instance_lock(loc);
+  type = (*loc->ops->node_type_h)(loc);
+  rtems_filesystem_instance_unlock(loc);
+
+  return type;
+}
diff --git a/cpukit/libcsupport/src/symlink.c b/cpukit/libcsupport/src/symlink.c
index be29980911..3a3eabc9e9 100644
--- a/cpukit/libcsupport/src/symlink.c
+++ b/cpukit/libcsupport/src/symlink.c
@@ -12,31 +12,31 @@
  */
 
 #if HAVE_CONFIG_H
-#include "config.h"
+  #include "config.h"
 #endif
 
+#include <unistd.h>
+
 #include <rtems/libio_.h>
-#include <rtems/seterr.h>
 
-int symlink(
-  const char *actualpath,
-  const char *sympath
-)
+int symlink( const char *path1, const char *path2 )
 {
-  rtems_filesystem_location_info_t    loc;
-  int                                 i;
-  const char                         *name_start;
-  int                                 result;
-
-  rtems_filesystem_get_start_loc( sympath, &i, &loc );
-
-  result = (*loc.ops->evalformake_h)( &sympath[i], &loc, &name_start );
-  if ( result != 0 )
-    return -1;
-
-  result = (*loc.ops->symlink_h)( &loc, actualpath, name_start);
-
-  rtems_filesystem_freenode( &loc );
-
-  return result;
+  int rv = 0;
+  rtems_filesystem_eval_path_context_t ctx;
+  int eval_flags = RTEMS_LIBIO_FOLLOW_HARD_LINK
+    | RTEMS_LIBIO_MAKE
+    | RTEMS_LIBIO_EXCLUSIVE;
+  const rtems_filesystem_location_info_t *currentloc =
+    rtems_filesystem_eval_path_start( &ctx, path2, eval_flags );
+
+  rv = (*currentloc->ops->symlink_h)(
+    currentloc,
+    rtems_filesystem_eval_path_get_token( &ctx ),
+    rtems_filesystem_eval_path_get_tokenlen( &ctx ),
+    path1
+  );
+
+  rtems_filesystem_eval_path_cleanup( &ctx );
+
+  return rv;
 }
diff --git a/cpukit/libcsupport/src/umask.c b/cpukit/libcsupport/src/umask.c
index 32bf79e2b9..1c34acf10b 100644
--- a/cpukit/libcsupport/src/umask.c
+++ b/cpukit/libcsupport/src/umask.c
@@ -12,22 +12,27 @@
  */
 
 #if HAVE_CONFIG_H
-#include "config.h"
+  #include "config.h"
 #endif
 
-#include <sys/types.h>
+#define __RTEMS_VIOLATE_KERNEL_VISIBILITY__
+
 #include <sys/stat.h>
 
 #include <rtems/libio_.h>
 
-mode_t umask(
-  mode_t cmask
-)
+mode_t umask( mode_t cmask )
 {
   mode_t old_mask;
 
-  old_mask               = rtems_filesystem_umask;
-  rtems_filesystem_umask = cmask;
+  /*
+   * We must use the same protection mechanism as in
+   * rtems_libio_set_private_env().
+   */
+  _Thread_Disable_dispatch();
+  old_mask = rtems_filesystem_umask;
+  rtems_filesystem_umask = cmask & (S_IRWXU | S_IRWXG | S_IRWXO);
+  _Thread_Enable_dispatch();
 
   return old_mask;
 }
diff --git a/cpukit/libcsupport/src/unlink.c b/cpukit/libcsupport/src/unlink.c
index bb28959b6d..f8f91705ca 100644
--- a/cpukit/libcsupport/src/unlink.c
+++ b/cpukit/libcsupport/src/unlink.c
@@ -12,75 +12,39 @@
  */
 
 #if HAVE_CONFIG_H
-#include "config.h"
+  #include "config.h"
 #endif
 
-#include <errno.h>
+#include <unistd.h>
 
 #include <rtems/libio_.h>
-#include <rtems/seterr.h>
 
-int unlink(
-  const char *path
-)
+int unlink( const char *path )
 {
-  int                               parentpathlen;
-  const char                       *name;
-  rtems_filesystem_location_info_t  parentloc;
-  rtems_filesystem_location_info_t  loc;
-  int                               i;
-  int                               result;
-  bool                              free_parentloc = false;
-
-  /*
-   * Get the node to be unlinked. Find the parent path first.
-   */
-
-  parentpathlen = rtems_filesystem_dirname ( path );
-
-  if ( parentpathlen == 0 )
-    rtems_filesystem_get_start_loc( path, &i, &parentloc );
-  else {
-    result = rtems_filesystem_evaluate_path( path, parentpathlen,
-                                             RTEMS_LIBIO_PERMS_WRITE,
-                                             &parentloc,
-                                             false );
-    if ( result != 0 )
-      return -1;
-
-    free_parentloc = true;
-  }
-
-  /*
-   * Start from the parent to find the node that should be under it.
-   */
-
-  loc = parentloc;
-  name = path + parentpathlen;
-  name += rtems_filesystem_prefix_separators( name, strlen( name ) );
-
-  result = rtems_filesystem_evaluate_relative_path( name , strlen( name ),
-                                                    0, &loc, false );
-  if ( result != 0 ) {
-    if ( free_parentloc )
-      rtems_filesystem_freenode( &parentloc );
-    return -1;
-  }
-
-  if (  (*loc.ops->node_type_h)( &loc ) == RTEMS_FILESYSTEM_DIRECTORY ) {
-    rtems_filesystem_freenode( &loc );
-    if ( free_parentloc )
-      rtems_filesystem_freenode( &parentloc );
-    rtems_set_errno_and_return_minus_one( EISDIR );
-  }
-
-  result = (*loc.ops->unlink_h)( &parentloc, &loc );
-
-  rtems_filesystem_freenode( &loc );
-  if ( free_parentloc )
-    rtems_filesystem_freenode( &parentloc );
-
-  return result;
+  int rv = 0;
+  rtems_filesystem_eval_path_context_t ctx;
+  int eval_flags = RTEMS_LIBIO_REJECT_TERMINAL_DOT;
+  rtems_filesystem_location_info_t parentloc;
+  int parent_eval_flags = RTEMS_LIBIO_PERMS_WRITE
+    | RTEMS_LIBIO_PERMS_SEARCH
+    | RTEMS_LIBIO_FOLLOW_LINK;
+  const rtems_filesystem_location_info_t *currentloc =
+    rtems_filesystem_eval_path_start_with_parent(
+      &ctx,
+      path,
+      eval_flags,
+      &parentloc,
+      parent_eval_flags
+    );
+
+  rv = (*currentloc->ops->rmnod_h)(
+    &parentloc,
+    currentloc
+  );
+
+  rtems_filesystem_eval_path_cleanup_with_parent( &ctx, &parentloc );
+
+  return rv;
 }
 
 /*
diff --git a/cpukit/libcsupport/src/unmount.c b/cpukit/libcsupport/src/unmount.c
index a2c67f7098..5f65e588d0 100644
--- a/cpukit/libcsupport/src/unmount.c
+++ b/cpukit/libcsupport/src/unmount.c
@@ -17,146 +17,37 @@
  */
 
 #if HAVE_CONFIG_H
-#include "config.h"
+  #include "config.h"
 #endif
 
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <unistd.h>
 #include <errno.h>
-#include <stdlib.h>
-#include <string.h>
 
 #include <rtems/libio_.h>
-#include <rtems/seterr.h>
-#include <rtems/chain.h>
 
-static bool is_fs_below_mount_point(
-  const rtems_filesystem_mount_table_entry_t *mt_entry,
-  void *arg
-)
+int unmount( const char *path )
 {
-  return arg == mt_entry->mt_point_node.mt_entry;
-}
-
-/*
- *  unmount
- *
- *  This routine will attempt to unmount the file system that has been
- *  is mounted a path.  If the operation is successful, 0 will
- *  be returned to the calling routine.  Otherwise, 1 will be returned.
- */
-
-int unmount(
-  const char *path
-)
-{
-  rtems_filesystem_location_info_t      loc;
-  rtems_filesystem_location_info_t     *fs_root_loc;
-  rtems_filesystem_location_info_t     *fs_mount_loc;
-  rtems_filesystem_mount_table_entry_t *mt_entry;
-
-  /*
-   *  Get
-   *    The root node of the mounted filesytem.
-   *    The node for the directory that the fileystem is mounted on.
-   *    The mount entry that is being refered to.
-   */
-
-  if ( rtems_filesystem_evaluate_path( path, strlen( path ), 0x0, &loc, true ) )
-    return -1;
-
-  mt_entry     = loc.mt_entry;
-  fs_mount_loc = &mt_entry->mt_point_node;
-  fs_root_loc  = &mt_entry->mt_fs_root;
-
-  /*
-   * Verify this is the root node for the file system to be unmounted.
-   */
-
-  if ( fs_root_loc->node_access != loc.node_access ){
-    rtems_filesystem_freenode( &loc );
-    rtems_set_errno_and_return_minus_one( EACCES );
-  }
-
-  /*
-   * Free the loc node and just use the nodes from the mt_entry .
-   */
-
-  rtems_filesystem_freenode( &loc );
-
-  /*
-   *  Verify the current node is not in this filesystem.
-   *  XXX - Joel I have a question here wasn't code added
-   *        that made the current node thread based instead
-   *        of system based?  I thought it was but it doesn't
-   *        look like it in this version.
-   */
-
-  if ( rtems_filesystem_current.mt_entry == mt_entry )
-    rtems_set_errno_and_return_minus_one( EBUSY );
-
-  /*
-   *  Verify there are no file systems below the path specified
-   */
-
-  if ( rtems_filesystem_mount_iterate( is_fs_below_mount_point,
-                                       fs_root_loc->mt_entry ) )
-    rtems_set_errno_and_return_minus_one( EBUSY );
-
-  /*
-   *  Run the file descriptor table to determine if there are any file
-   *  descriptors that are currently active and reference nodes in the
-   *  file system that we are trying to unmount
-   */
-
-  if ( rtems_libio_is_open_files_in_fs( mt_entry ) == 1 )
-    rtems_set_errno_and_return_minus_one( EBUSY );
-
-  /*
-   * Allow the file system being unmounted on to do its cleanup.
-   * If it fails it will set the errno to the approprate value
-   * and the fileystem will not be modified.
-   */
-
-  if (( fs_mount_loc->ops->unmount_h )( mt_entry ) != 0 )
-    return -1;
-
-  /*
-   *  Allow the mounted filesystem to unmark the use of the root node.
-   *
-   *  Run the unmount function for the subordinate file system.
-   *
-   *  If we fail to unmount the filesystem remount it on the base filesystems
-   *  directory node.
-   *
-   *  NOTE:  Fatal error is called in a case which should never happen
-   *         This was response was questionable but the best we could
-   *         come up with.
-   */
-
-  if ((fs_root_loc->ops->fsunmount_me_h )( mt_entry ) != 0){
-    if (( fs_mount_loc->ops->mount_h )( mt_entry ) != 0 )
-      rtems_fatal_error_occurred( 0 );
-    return -1;
+  int rv = 0;
+  rtems_filesystem_eval_path_context_t ctx;
+  int eval_flags = RTEMS_LIBIO_FOLLOW_LINK;
+  const rtems_filesystem_location_info_t *currentloc =
+    rtems_filesystem_eval_path_start( &ctx, path, eval_flags );
+  rtems_filesystem_mount_table_entry_t *mt_entry = currentloc->mt_entry;
+
+  if ( rtems_filesystem_location_is_root( currentloc ) ) {
+    rv = (*mt_entry->mt_point_node->location.ops->unmount_h)( mt_entry );
+    if ( rv == 0 ) {
+      rtems_filesystem_mt_entry_declare_lock_context( lock_context );
+
+      rtems_filesystem_mt_entry_lock( lock_context );
+      mt_entry->mounted = false;
+      rtems_filesystem_mt_entry_unlock( lock_context );
+    }
+  } else {
+    errno = EACCES;
+    rv = -1;
   }
 
-  /*
-   *  Extract the mount table entry from the chain
-   */
-
-  rtems_libio_lock();
-  rtems_chain_extract( &mt_entry->Node );
-  rtems_libio_unlock();
-
-  /*
-   *  Free the memory node that was allocated in mount
-   *  Free the memory associated with the extracted mount table entry.
-   */
-
-  rtems_filesystem_freenode( fs_mount_loc );
-  free( mt_entry );
+  rtems_filesystem_eval_path_cleanup( &ctx );
 
-  return 0;
+  return rv;
 }
diff --git a/cpukit/libcsupport/src/utime.c b/cpukit/libcsupport/src/utime.c
index 25bcb0761b..49158700c0 100644
--- a/cpukit/libcsupport/src/utime.c
+++ b/cpukit/libcsupport/src/utime.c
@@ -12,36 +12,41 @@
  */
 
 #if HAVE_CONFIG_H
-#include "config.h"
+  #include "config.h"
 #endif
 
+/* FIXME: This include is a workaround for a broken <utime.h> in Newlib */
 #include <sys/types.h>
+
 #include <utime.h>
-#include <errno.h>
 
 #include <rtems/libio_.h>
-#include <rtems/seterr.h>
 
-int utime(
-  const char           *path,
-  const struct utimbuf *times
-)
+int utime( const char *path, const struct utimbuf *times )
 {
-  rtems_filesystem_location_info_t   temp_loc;
-  int                                result;
-  struct utimbuf                     now;
-
-  if ( rtems_filesystem_evaluate_path( path, strlen( path ), 0x00, &temp_loc, true ) )
-    return -1;
+  int rv = 0;
+  rtems_filesystem_eval_path_context_t ctx;
+  int eval_flags = RTEMS_LIBIO_FOLLOW_LINK;
+  const rtems_filesystem_location_info_t *currentloc =
+    rtems_filesystem_eval_path_start( &ctx, path, eval_flags );
+  struct utimbuf now_times;
 
   if ( times == NULL ) {
-    now.actime = now.modtime = time( NULL );
-    times = &now;
+    time_t now = time( NULL );
+
+    now_times.actime = now;
+    now_times.modtime = now;
+
+    times = &now_times;
   }
 
-  result = (*temp_loc.ops->utime_h)( &temp_loc, times->actime, times->modtime );
+  rv = (*currentloc->ops->utime_h)(
+    currentloc,
+    times->actime,
+    times->modtime
+  );
 
-  rtems_filesystem_freenode( &temp_loc );
+  rtems_filesystem_eval_path_cleanup( &ctx );
 
-  return result;
+  return rv;
 }