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.

1 files changed, 52 insertions, 56 deletions

diff --git a/testsuites/psxtests/psxmount/test.c b/testsuites/psxtests/psxmount/test.c
index 7e1c84fcda..1e80376685 100644
--- a/testsuites/psxtests/psxmount/test.c
+++ b/testsuites/psxtests/psxmount/test.c
@@ -1,23 +1,10 @@
 /*
- *  This is a native test to explore how the readdir() family works.
- *  Newlib supports the following readdir() family members:
- *
- *    closedir()   -
- *    readdir()    -
- *    scandir()    -
- *    opendir()    -
- *    rewinddir()  -
- *    telldir()    - BSD not in POSIX
- *    seekdir()    - BSD not in POSIX
- *
- *
- *  seekdir() takes an offset which is a byte offset.  The Linux
- *  implementation of this appears to seek to the ((off/DIRENT_SIZE) + 1)
- *  record where DIRENT_SIZE seems to be 12 bytes.
- *
  *  COPYRIGHT (c) 1989-2009.
  *  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.
@@ -41,8 +28,6 @@
 #include <rtems/libio.h>
 #include <pmacros.h>
 
-extern rtems_filesystem_location_info_t rtems_filesystem_current;
-
 DIR *directory;
 DIR *directory2;
 DIR *directory3;
@@ -100,7 +85,9 @@ int main(
   int status;
   struct stat statbuf;
   static char mount_point_string[25] = { "/c/z/my_mount_point" };
-
+  static const char my_sub_fs_dir [] = "/c/y/my_mount_point/my_sub_fs_dir";
+  static const char my_link [] = "/c/y/my_link";
+  static const char mount_point [] = "/c/y/my_mount_point";
 
   printf( "\n\n*** MOUNT/UNMOUNT TEST ***\n" );
 
@@ -293,7 +280,7 @@ int main(
 
 
   /*
-   * Verify we cannot unmount a file system while we are in it.
+   * Verify we can unmount a file system while we are in it.
    */
 
   printf("Create and chdir to /c/y/my_mount_point/mydir\n");
@@ -303,22 +290,27 @@ int main(
   status = chdir( "/c/y/my_mount_point/mydir" );
   rtems_test_assert( status == 0 );
 
-  printf("unmount of /c/y/my_mount_point should fail with EBUSY\n");
+  printf("unmount of /c/y/my_mount_point\n");
   status = unmount( "/c/y/my_mount_point" );
+  rtems_test_assert( status == 0 );
+
+  printf("chdir to .. should fail with ENXIO\n");
+  status = chdir( ".." );
   rtems_test_assert( status == -1 );
-  rtems_test_assert( errno == EBUSY );
+  rtems_test_assert( errno == ENXIO );
 
   /*
-   * Chdir to root and verify we can unmount the file system now.
+   * Chdir to root and verify we unmounted the file system now.
    */
 
   printf("chdir to / and verify we can unmount /c/y/my_mount_point\n");
   status = chdir( "/" );
   rtems_test_assert( status == 0 );
 
-  printf("unmount /c/y/my_mount_point \n");
-  status = unmount( "/c/y/my_mount_point" );
-  rtems_test_assert( status == 0 );
+  printf("chdir to /c/y/my_mount_point/my_dir should fail with ENOENT\n");
+  status = chdir( "/c/y/my_mount_point/mydir" );
+  rtems_test_assert( status == -1 );
+  rtems_test_assert( errno == ENOENT );
 
   /*
    * Attempt to unmount a directory that does not exist.
@@ -344,7 +336,7 @@ int main(
 
   /*
    * Create a file and directory then open the directory.
-   * Verify unmount will return EBUSY while directory is open.
+   * Verify unmount will return successful while directory is open.
    */
 
   printf("Create and open /c/y/my_mount_point/my_file\n");
@@ -353,21 +345,34 @@ int main(
   status = close( fd );
   rtems_test_assert( status == 0 );
 
-  printf("\nmkdir /c/y/my_mount_point/my_dir\n");
-  status = mkdir( "/c/y/my_mount_point/my_dir", 0x1c0 );
-  printf("Open /c/y/my_mount_point/my_dir\n");
-  directory = opendir( "/c/y/my_mount_point/my_dir" );
+  printf("\nmkdir %s\n", my_sub_fs_dir );
+  status = mkdir( my_sub_fs_dir, S_IRWXU );
+
+  printf("open %s\n", my_sub_fs_dir );
+  directory = opendir( my_sub_fs_dir );
   rtems_test_assert( directory );
 
-  printf("Unmount /c/y/my_mount_point should fail with EBUSY\n");
-  status = unmount( "/c/y/my_mount_point" );
+  printf("mkdir %s should fail with EEXIST\n", my_sub_fs_dir );
+  status = mkdir( my_sub_fs_dir, S_IRWXU );
   rtems_test_assert( status == -1 );
-  rtems_test_assert( errno == EBUSY );
+  rtems_test_assert( errno == EEXIST );
 
-  printf("Close /c/y/my_mount_point/my_dir\n");
+  printf("unmount %s\n", mount_point );
+  status = unmount( mount_point );
+  rtems_test_assert( status == 0 );
+
+  printf("close %s\n", my_sub_fs_dir );
   status = closedir( directory );
   rtems_test_assert( status == 0 );
 
+  printf("mkdir %s\n", my_sub_fs_dir );
+  status = mkdir( my_sub_fs_dir, S_IRWXU );
+  rtems_test_assert( status == 0 );
+
+  printf("rmdir %s\n", my_sub_fs_dir );
+  status = rmdir( my_sub_fs_dir );
+  rtems_test_assert( status == 0 );
+
   /*
    * Attempt to unmount a directory that is not a mount point.
    */
@@ -378,33 +383,27 @@ int main(
   rtems_test_assert( errno == EACCES );
 
   /*
-   * Verify a file system can not be unmounted with a mounted file system
-   * in it.
+   * Mount file system
    */
 
-  printf("Mount a file system at /c/y/my_mount_point/my_dir\n");
+  printf("Mount a file system at %s\n", mount_point);
   status = mount(
      "null",
-     "/c/y/my_mount_point/my_dir",
+     mount_point,
      "imfs",
      RTEMS_FILESYSTEM_READ_WRITE,
      NULL );
   rtems_test_assert( status == 0 );
 
-  printf("unmount /c/y/my_mount_point should fail with EBUSY\n");
-  status = unmount( "/c/y/my_mount_point" );
-  rtems_test_assert( status == -1 );
-  rtems_test_assert( errno == EBUSY );
-
   /*
    * Verify you cannot create a hard link across mounted file systems.
    */
 
   printf("Verify a hard link across filesystems fails with EXDEV\n");
-  status = mkdir( "/c/y/my_mount_point/my_dir2", S_IRWXU  );
+  status = mkdir( my_sub_fs_dir, S_IRWXU  );
   rtems_test_assert( status == 0 );
 
-  status = link( "/c/y/my_mount_point/my_dir2", "/c/y/my_mount_point/my_dir/my_link" );
+  status = link( my_sub_fs_dir, my_link );
   rtems_test_assert( status == -1 );
   rtems_test_assert( errno == EXDEV );
 
@@ -413,13 +412,13 @@ int main(
    */
 
   printf("Verify a symbolic link across file systems works\n");
-  status = symlink( "/c/y/my_mount_point/my_dir2", "/c/y/my_mount_point/my_dir/my_link" );
+  status = symlink( my_sub_fs_dir, my_link );
   rtems_test_assert( status == 0 );
-  status = stat( "/c/y/my_mount_point/my_dir/my_link", &statbuf );
+  status = stat( my_link, &statbuf );
   rtems_test_assert( status == 0 );
 
-  printf("unmount /c/y/my_mount_point/my_dir\n");
-  status = unmount( "/c/y/my_mount_point/my_dir" );
+  printf("unmount %s\n", mount_point);
+  status = unmount( mount_point );
   rtems_test_assert( status == 0 );
 
   /*
@@ -427,12 +426,9 @@ int main(
    */
 
   printf("Verify the symbolic link now fails\n");
-  status = stat( "/c/y/my_mount_point/my_dir/my_link", &statbuf );
-  rtems_test_assert( status != 0 );
-
-  printf("unmount /c/y/my_mount_point\n");
-  status = unmount( "/c/y/my_mount_point" );
-  rtems_test_assert( status == 0 );
+  status = stat( my_link, &statbuf );
+  rtems_test_assert( status == -1 );
+  rtems_test_assert( errno == ENOENT );
 
   printf( "\n\n*** END OF MOUNT/UNMOUNT TEST ***\n" );
   rtems_test_exit(0);