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, 57 insertions, 129 deletions

diff --git a/cpukit/libfs/src/imfs/imfs.h b/cpukit/libfs/src/imfs/imfs.h
index b412c2a1fe..2a851acae4 100644
--- a/cpukit/libfs/src/imfs/imfs.h
+++ b/cpukit/libfs/src/imfs/imfs.h
@@ -18,13 +18,9 @@
 #ifndef _RTEMS_IMFS_H
 #define _RTEMS_IMFS_H
 
-#include <rtems.h>
-#include <rtems/chain.h>
-
-#include <sys/types.h>
 #include <limits.h>
-#include <rtems/libio.h>
 
+#include <rtems/libio_.h>
 #include <rtems/pipe.h>
 
 #ifdef __cplusplus
@@ -32,15 +28,6 @@ extern "C" {
 #endif
 
 /*
- *  File name macros
- */
-
-#define IMFS_is_valid_name_char( _ch ) ( 1 )
-
-#define IMFS_is_separator( _ch ) \
-   rtems_filesystem_is_separator( _ch )
-
-/*
  *  Data types
  */
 
@@ -226,22 +213,11 @@ typedef struct {
   ino_t                                   ino_count;
   const rtems_filesystem_file_handlers_r *memfile_handlers;
   const rtems_filesystem_file_handlers_r *directory_handlers;
+  const rtems_filesystem_file_handlers_r *link_handlers;
   const rtems_filesystem_file_handlers_r *fifo_handlers;
 } IMFS_fs_info_t;
 
 /*
- *  Type defination for tokens returned from IMFS_get_token
- */
-
-typedef enum {
-  IMFS_NO_MORE_PATH,
-  IMFS_CURRENT_DIR,
-  IMFS_UP_DIR,
-  IMFS_NAME,
-  IMFS_INVALID_TOKEN
-} IMFS_token_types;
-
-/*
  *  Shared Data
  */
 
@@ -276,29 +252,18 @@ extern int miniIMFS_initialize(
 extern int IMFS_initialize_support(
    rtems_filesystem_mount_table_entry_t       *mt_entry,
    const rtems_filesystem_operations_table    *op_table,
-   const rtems_filesystem_file_handlers_r     *memfile_handlers,
-   const rtems_filesystem_file_handlers_r     *directory_handlers,
+   const rtems_filesystem_file_handlers_r     *link_handlers,
    const rtems_filesystem_file_handlers_r     *fifo_handlers
 );
 
-extern int IMFS_fsunmount(
+extern void IMFS_fsunmount(
    rtems_filesystem_mount_table_entry_t *mt_entry
 );
 
 extern int rtems_tarfs_load(
-   char         *mountpoint,
-   uint8_t      *tar_image,
-   size_t        tar_size
-);
-
-/*
- * Returns the number of characters copied from path to token.
- */
-extern IMFS_token_types IMFS_get_token(
-  const char       *path,
-  int               pathlen,
-  char             *token,
-  int              *token_len
+   const char *mountpoint,
+   uint8_t *tar_image,
+   size_t tar_size
 );
 
 extern void IMFS_dump( void );
@@ -309,88 +274,59 @@ extern void IMFS_dump( void );
  */
 extern int IMFS_memfile_maximum_size( void );
 
-extern void IMFS_initialize_jnode(
-  IMFS_jnode_t        *the_jnode,
-  IMFS_jnode_types_t   type,
-  IMFS_jnode_t        *the_parent,
-  char                *name,
-  mode_t               mode
-);
-
-extern IMFS_jnode_t *IMFS_find_match_in_dir(
-  IMFS_jnode_t *directory,                         /* IN */
-  char         *name                               /* IN */
-);
 
 extern rtems_filesystem_node_types_t IMFS_node_type(
-  rtems_filesystem_location_info_t    *pathloc     /* IN */
+  const rtems_filesystem_location_info_t *loc
 );
 
 extern int IMFS_stat(
-  rtems_filesystem_location_info_t *loc,           /* IN  */
-  struct stat                      *buf            /* OUT */
-);
-
-extern int IMFS_Set_handlers(
-  rtems_filesystem_location_info_t   *loc
+  const rtems_filesystem_location_info_t *loc,
+  struct stat *buf
 );
 
-extern int IMFS_evaluate_link(
-  rtems_filesystem_location_info_t *node,        /* IN/OUT */
-  int                               flags        /* IN     */
-);
+extern void IMFS_Set_handlers( rtems_filesystem_location_info_t *loc );
 
-extern int IMFS_eval_path(
-  const char                        *pathname,     /* IN     */
-  size_t                            pathnamelen,   /* IN     */
-  int                               flags,         /* IN     */
-  rtems_filesystem_location_info_t  *pathloc       /* IN/OUT */
+extern void IMFS_eval_path(
+  rtems_filesystem_eval_path_context_t *ctx
 );
 
 extern int IMFS_link(
-  rtems_filesystem_location_info_t  *to_loc,      /* IN */
-  rtems_filesystem_location_info_t  *parent_loc,  /* IN */
-  const char                        *token        /* IN */
-);
-
-extern int IMFS_unlink(
-  rtems_filesystem_location_info_t  *parent_pathloc, /* IN */
-  rtems_filesystem_location_info_t  *pathloc         /* IN */
+  const rtems_filesystem_location_info_t *parentloc,
+  const rtems_filesystem_location_info_t *targetloc,
+  const char *name,
+  size_t namelen
 );
 
 extern int IMFS_chown(
-  rtems_filesystem_location_info_t  *pathloc,      /* IN */
-  uid_t                              owner,        /* IN */
-  gid_t                              group         /* IN */
+  const rtems_filesystem_location_info_t *loc,
+  uid_t owner,
+  gid_t group
 );
 
 extern int IMFS_mknod(
-  const char                        *path,         /* IN */
-  mode_t                             mode,         /* IN */
-  dev_t                              dev,          /* IN */
-  rtems_filesystem_location_info_t  *pathloc       /* IN/OUT */
+  const rtems_filesystem_location_info_t *parentloc,
+  const char *name,
+  size_t namelen,
+  mode_t mode,
+  dev_t dev
 );
 
 extern IMFS_jnode_t *IMFS_allocate_node(
   IMFS_jnode_types_t                type,         /* IN  */
   const char                       *name,         /* IN  */
+  size_t                            namelen,      /* IN  */
   mode_t                            mode          /* IN  */
 );
 
 extern IMFS_jnode_t *IMFS_create_root_node(void);
 
 extern IMFS_jnode_t *IMFS_create_node(
-  rtems_filesystem_location_info_t *parent_loc,   /* IN  */
-  IMFS_jnode_types_t                type,         /* IN  */
-  const char                       *name,         /* IN  */
-  mode_t                            mode,         /* IN  */
-  const IMFS_types_union           *info          /* IN  */
-);
-
-extern int IMFS_evaluate_for_make(
-  const char                         *path,       /* IN     */
-  rtems_filesystem_location_info_t   *pathloc,    /* IN/OUT */
-  const char                        **name        /* OUT    */
+  const rtems_filesystem_location_info_t *pathloc, /* IN  */
+  IMFS_jnode_types_t                      type,    /* IN  */
+  const char                             *name,    /* IN  */
+  size_t                                  namelen, /* IN  */
+  mode_t                                  mode,    /* IN  */
+  const IMFS_types_union                 *info     /* IN  */
 );
 
 extern int IMFS_mount(
@@ -413,8 +349,8 @@ extern int memfile_ftruncate(
 extern int imfs_dir_open(
   rtems_libio_t *iop,             /* IN  */
   const char    *pathname,        /* IN  */
-  uint32_t       flag,            /* IN  */
-  uint32_t       mode             /* IN  */
+  int            oflag,           /* IN  */
+  mode_t         mode             /* IN  */
 );
 
 extern int imfs_dir_close(
@@ -433,21 +369,11 @@ extern off_t imfs_dir_lseek(
   int                   whence            /* IN  */
 );
 
-extern int imfs_dir_fstat(
-  rtems_filesystem_location_info_t *loc,         /* IN  */
-  struct stat                      *buf          /* OUT */
-);
-
-extern int imfs_dir_rmnod(
-  rtems_filesystem_location_info_t *parent_pathloc, /* IN */
-  rtems_filesystem_location_info_t *pathloc         /* IN */
-);
-
 extern int memfile_open(
   rtems_libio_t *iop,             /* IN  */
   const char    *pathname,        /* IN  */
-  uint32_t       flag,            /* IN  */
-  uint32_t       mode             /* IN  */
+  int            oflag,           /* IN  */
+  mode_t         mode             /* IN  */
 );
 
 extern int memfile_close(
@@ -481,8 +407,8 @@ extern off_t memfile_lseek(
 extern int device_open(
   rtems_libio_t *iop,            /* IN  */
   const char    *pathname,       /* IN  */
-  uint32_t       flag,           /* IN  */
-  uint32_t       mode            /* IN  */
+  int            oflag,          /* IN  */
+  mode_t         mode            /* IN  */
 );
 
 extern int device_close(
@@ -519,33 +445,35 @@ extern int device_ftruncate(
 );
 
 extern int IMFS_utime(
-  rtems_filesystem_location_info_t  *pathloc,       /* IN */
-  time_t                             actime,        /* IN */
-  time_t                             modtime        /* IN */
+  const rtems_filesystem_location_info_t *loc,
+  time_t actime,
+  time_t modtime
 );
 
 extern int IMFS_fchmod(
-  rtems_filesystem_location_info_t *loc,
-  mode_t                            mode
+  const rtems_filesystem_location_info_t *loc,
+  mode_t mode
 );
 
 extern int IMFS_symlink(
-  rtems_filesystem_location_info_t  *parent_loc,  /* IN */
-  const char                        *link_name,
-  const char                        *node_name
+  const rtems_filesystem_location_info_t *parentloc,
+  const char *name,
+  size_t namelen,
+  const char *target
 );
 
 extern ssize_t IMFS_readlink(
- rtems_filesystem_location_info_t   *loc,         /* IN */
- char                               *buf,         /* OUT */
- size_t                             bufsize
+  const rtems_filesystem_location_info_t *loc,
+  char *buf,
+  size_t bufsize
 );
 
 extern int IMFS_rename(
-  rtems_filesystem_location_info_t  *old_loc,         /* IN */
-  rtems_filesystem_location_info_t  *old_parent_loc,  /* IN */
-  rtems_filesystem_location_info_t  *new_parent_loc,  /* IN */
-  const char                        *new_name         /* IN */
+  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
 );
 
 extern int IMFS_fdatasync(
@@ -561,8 +489,8 @@ extern void IMFS_check_node_remove(
 );
 
 extern int IMFS_rmnod(
-  rtems_filesystem_location_info_t  *parent_pathloc, /* IN */
-  rtems_filesystem_location_info_t  *pathloc         /* IN */
+  const rtems_filesystem_location_info_t *parentloc,
+  const rtems_filesystem_location_info_t *loc
 );
 
 /*