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authorJoel Sherrill <joel.sherrill@OARcorp.com>1999-10-12 21:54:40 +0000
committerJoel Sherrill <joel.sherrill@OARcorp.com>1999-10-12 21:54:40 +0000
commit7441fe2c5b1275339177a1aef778c9a9620dc462 (patch)
tree9e82a36663db1ab1d9993cc31cadfc16ef8a3f73
parentDispersed. (diff)
downloadrtems-7441fe2c5b1275339177a1aef778c9a9620dc462.tar.bz2
Made many changes to turn the outline into something more like a manual
and less like a collection of notes.
-rw-r--r--doc/filesystem/Makefile18
-rw-r--r--doc/filesystem/filesystem.texi8
-rw-r--r--doc/filesystem/fsrequirements.t1225
-rw-r--r--doc/filesystem/imfs.t716
-rw-r--r--doc/filesystem/init.t74
-rw-r--r--doc/filesystem/mounting.t20
-rw-r--r--doc/filesystem/patheval.t10
-rw-r--r--doc/filesystem/preface.texi57
-rw-r--r--doc/filesystem/syscalls.t174
9 files changed, 1854 insertions, 448 deletions
diff --git a/doc/filesystem/Makefile b/doc/filesystem/Makefile
index a9af386a68..e227d8fd55 100644
--- a/doc/filesystem/Makefile
+++ b/doc/filesystem/Makefile
@@ -21,9 +21,9 @@ dirs:
COMMON_FILES=../common/cpright.texi ../common/setup.texi
-GENERATED_FILES=basefs.texi applayering.texi patheval.texi \
- init.texi mounting.texi lifecycle.texi imfs.texi \
- syscalls.texi basefs.texi
+GENERATED_FILES=patheval.texi \
+ init.texi mounting.texi fsrequirements.texi imfs.texi \
+ syscalls.texi
FILES= $(PROJECT).texi \
preface.texi $(GENERATED_FILES)
@@ -53,16 +53,6 @@ $(PROJECT).dvi: $(FILES)
$(TEXI2DVI) $(PROJECT).texi
cp $(PROJECT).dvi $(WWW_INSTALL)/$(PROJECT)
-basefs.texi: basefs.t Makefile
- $(BMENU) -p "Preface" \
- -u "Top" \
- -n "" ${*}.t
-
-applayering.texi: applayering.t Makefile
- $(BMENU) -p "" \
- -u "Top" \
- -n "" ${*}.t
-
patheval.texi: patheval.t Makefile
$(BMENU) -p "" \
-u "Top" \
@@ -78,7 +68,7 @@ mounting.texi: mounting.t Makefile
-u "Top" \
-n "" ${*}.t
-lifecycle.texi: lifecycle.t Makefile
+fsrequirements.texi: fsrequirements.t Makefile
$(BMENU) -p "" \
-u "Top" \
-n "" ${*}.t
diff --git a/doc/filesystem/filesystem.texi b/doc/filesystem/filesystem.texi
index 41ea89ac38..f18a466b40 100644
--- a/doc/filesystem/filesystem.texi
+++ b/doc/filesystem/filesystem.texi
@@ -63,12 +63,10 @@ END-INFO-DIR-ENTRY
@c The alternative is to rework a sentence to avoid this problem.
@include preface.texi
-@include basefs.texi
-@include applayering.texi
@include patheval.texi
@include init.texi
@include mounting.texi
-@include lifecycle.texi
+@include fsrequirements.texi
@include imfs.texi
@include syscalls.texi
@ifinfo
@@ -79,12 +77,10 @@ This is the online version of the RTEMS Filesystem Design Guide.
@menu
* Preface::
-* Base Filesystem::
-* Applications and Functional Layering::
* Pathname Evaluation::
* System Initialization::
* Mounting and Unmounting Filesystems::
-* Filesystem Lifecycle::
+* Filesystem Requirements::
* In-Memory Filesystem::
* System Call Development Notes::
* Command and Variable Index::
diff --git a/doc/filesystem/fsrequirements.t b/doc/filesystem/fsrequirements.t
index 32e06e627a..3bb8fe8e03 100644
--- a/doc/filesystem/fsrequirements.t
+++ b/doc/filesystem/fsrequirements.t
@@ -12,7 +12,85 @@
This chapter details the behavioral requirements that all filesystem
implementations must adhere to.
-@section Filesystem File and Directory Removal Constraints
+@section General
+
+The RTEMS filesystem framework was intended to be compliant with the
+POSIX Files and Directories interface standard. The following filesystem
+characteristics resulted in a functional switching layer.
+
+@example
+Figure of the Filesystem Functional Layering goes here.
+This figure includes networking and disk caching layering.
+@end example
+
+@ifset use-ascii
+@example
+@group
+@end group
+@end example
+@end ifset
+
+@ifset use-tex
+@c @image{FunctionalLayerCake,6in,4in}
+@end ifset
+
+@ifset use-html
+@end ifset
+
+@enumerate
+
+@item Application programs are presented with a standard set of POSIX
+compliant functions that allow them to interface with the files, devices
+and directories in the filesystem. The interfaces to these routines do
+not reflect the type of subordinate filesystem implementation in which
+the file will be found.
+
+@item The filesystem framework developed under RTEMS allows for mounting
+filesystem of different types under the base filesystem.
+
+@item The mechanics of locating file information may be quite different
+between filesystem types.
+
+@item The process of locating a file may require crossing filesystem
+boundaries.
+
+@item The transitions between filesystem and the processing required to
+access information in different filesystem is not visible at the level
+of the POSIX function call.
+
+@item The POSIX interface standard provides file access by character
+pathname to the file in some functions and through an integer file
+descriptor in other functions.
+
+@item The nature of the integer file descriptor and its associated
+processing is operating system and filesystem specific.
+
+@item Directory and device information must be processed with some of the
+same routines that apply to files.
+
+@item The form and content of directory and device information differs
+greatly from that of a regular file.
+
+@item Files, directories and devices represent elements (nodes) of a tree
+hierarchy.
+
+@item The rules for processing each of the node types that exist under the
+filesystem are node specific but are still not reflected in the POSIX
+interface routines.
+
+@end enumerate
+
+
+@example
+Figure of the Filesystem Functional Layering goes here.
+This figure focuses on the Base Filesystem and IMFS.
+@end example
+
+@example
+Figure of the IMFS Memfile control blocks
+@end example
+
+@section File and Directory Removal Constraints
The following POSIX constraints must be honored by all filesystems.
@@ -32,3 +110,1148 @@ link count must be less than one to allow for removal of the node.
@end itemize
+@c
+@c
+@c
+@section API Layering
+
+@subsection Mapping of Generic System Calls to Filesystem Specific Functions
+
+The list of generic system calls includes the routines open(), read(),
+write(), close(), etc..
+
+The Files and Directories section of the POSIX Application Programs
+Interface specifies a set of functions with calling arguments that are
+used to gain access to the information in a filesystem. To the
+application program, these functions allow access to information in any
+mounted filesystem without explicit knowledge of the filesystem type or
+the filesystem mount configuration. The following are functions that are
+provided to the application:
+
+@enumerate
+@item access()
+@item chdir()
+@item chmod()
+@item chown()
+@item close()
+@item closedir()
+@item fchmod()
+@item fcntl()
+@item fdatasync()
+@item fpathconf()
+@item fstat()
+@item fsync()
+@item ftruncate()
+@item link()
+@item lseek()
+@item mkdir()
+@item mknod()
+@item mount()
+@item open()
+@item opendir()
+@item pathconf()
+@item read()
+@item readdir()
+@item rewinddir()
+@item rmdir()
+@item rmnod()
+@item scandir()
+@item seekdir()
+@item stat()
+@item telldir()
+@item umask()
+@item unlink()
+@item unmount()
+@item utime()
+@item write()
+@end enumerate
+
+The filesystem's type as well as the node type within the filesystem
+determine the nature of the processing that must be performed for each of
+the functions above. The RTEMS filesystem provides a framework that
+allows new filesystem to be developed and integrated without alteration
+to the basic framework.
+
+To provide the functional switching that is required, each of the POSIX
+file and directory functions have been implemented as a shell function.
+The shell function adheres to the POSIX interface standard. Within this
+functional shell, filesystem and node type information is accessed which
+is then used to invoke the appropriate filesystem and node type specific
+routine to process the POSIX function call.
+
+@subsection File/Device/Directory function access via file control block - rtems_libio_t structure
+
+The POSIX open() function returns an integer file descriptor that is used
+as a reference to file control block information for a specific file. The
+file control block contains information that is used to locate node, file
+system, mount table and functional handler information. The diagram in
+Figure 8 depicts the relationship between and among the following
+components.
+
+@enumerate
+
+@item File Descriptor Table
+
+This is an internal RTEMS structure that tracks all currently defined file
+descriptors in the system. The index that is returned by the file open()
+operation references a slot in this table. The slot contains a pointer to
+the file descriptor table entry for this file. The rtems_libio_t structure
+represents the file control block.
+
+@item Allocation of entry in the File Descriptor Table
+
+Access to the file descriptor table is controlled through a semaphore that
+is implemented using the rtems_libio_allocate() function. This routine
+will grab a semaphore and then scan the file control blocks to determine
+which slot is free for use. The first free slot is marked as used and the
+index to this slot is returned as the file descriptor for the open()
+request. After the alterations have been made to the file control block
+table, the semaphore is released to allow further operations on the table.
+
+@item Maximum number of entries in the file descriptor table is
+configurable through the src/exec/sapi/headers/confdefs.h file. If the
+CONFIGURE_LIBIO_MAXIMUM_FILE_DESCRIPTORS constant is defined its value
+will represent the maximum number of file descriptors that are allowed.
+If CONFIGURE_LIBIO_MAXIMUM_FILE_DESCRIPTORS is not specified a default
+value of 20 will be used as the maximum number of file descriptors
+allowed.
+
+@item File control block - rtems_libio_t structure
+
+@example
+struct rtems_libio_tt @{
+ rtems_driver_name_t *driver;
+ off_t size; /* size of file */
+ off_t offset; /* current offset into file */
+ unsigned32 flags;
+ rtems_filesystem_location_info_t pathinfo;
+ Objects_Id sem;
+ unsigned32 data0; /* private to "driver" */
+ void data1; / . */
+ void file_info; /used by file handlers/
+ rtems_filesystem_file_handlers_r handlers; /type specific handlers/
+@};
+@end example
+
+A file control block can exist for regular files, devices and directories.
+The following fields are important for regular file and directory access:
+
+@itemize @bullet
+
+@item Size - For a file this represents the number of bytes currently
+stored in a file. For a directory this field is not filled in.
+
+@item Offset - For a file this is the byte file position index relative to
+the start of the file. For a directory this is the byte offset into a
+sequence of dirent structures.
+
+@item Pathinfo - This is a structure that provides a pointer to node
+information, OPS table functions, Handler functions and the mount table
+entry associated with this node.
+
+@item file_info - A pointer to node information that is used by Handler
+functions
+
+@item handlers - A pointer to a table of handler functions that operate on
+a file, device or directory through a file descriptor index
+
+@end itemize
+
+@end enumerate
+
+@subsection File/Directory function access via rtems_filesystem_location_info_t structure
+
+The rtems_filesystem_location_info_tt structure below provides sufficient
+information to process nodes under a mounted filesystem.
+
+@example
+struct rtems_filesystem_location_info_tt @{
+ void *node_access;
+ rtems_filesystem_file_handlers_r *handlers;
+ rtems_filesystem_operations_table *ops;
+ rtems_filesystem_mount_table_entry_t *mt_entry;
+@};
+@end example
+
+It contains a void pointer to filesystem specific nodal structure,
+pointers to the OPS table for the filesystem that contains the node, the
+node type specific handlers for the node and a reference pointer to the
+mount table entry associated with the filesystem containing the node
+
+@section Operation Tables
+
+Filesystem specific operations are invoked indirectly. The set of
+routines that implement the filesystem are configured into two tables.
+The Filesystem Handler Table has routines that are specific to a
+filesystem but remain constant regardless of the actual file type.
+The File Handler Table has routines that are both filesystem and file type
+specific.
+
+@subsection Filesystem Handler Table Functions
+
+OPS table functions are defined in a @code{rtems_filesystem_operations_table}
+structure. It defines functions that are specific to a given filesystem.
+One table exists for each filesystem that is supported in the RTEMS
+configuration. The structure definition appears below and is followed by
+general developmental information on each of the functions contained in this
+function management structure.
+
+@example
+typedef struct @{
+ rtems_filesystem_evalpath_t evalpath;
+ rtems_filesystem_evalmake_t evalformake;
+ rtems_filesystem_link_t link;
+ rtems_filesystem_unlink_t unlink;
+ rtems_filesystem_node_type_t node_type;
+ rtems_filesystem_mknod_t mknod;
+ rtems_filesystem_rmnod_t rmnod;
+ rtems_filesystem_chown_t chown;
+ rtems_filesystem_freenode_t freenod;
+ rtems_filesystem_mount_t mount;
+ rtems_filesystem_fsmount_me_t fsmount_me;
+ rtems_filesystem_unmount_t unmount;
+ rtems_filesystem_fsunmount_me_t fsunmount_me;
+ rtems_filesystem_utime_t utime;
+ rtems_filesystem_evaluate_link_t eval_link;
+ rtems_filesystem_symlink_t symlink;
+@} rtems_filesystem_operations_table;
+@end example
+
+@c
+@c
+@c
+@page
+
+@subsubsection evalpath Handler
+
+@subheading Corresponding Structure Element:
+
+XXX
+
+@subheading Arguments:
+
+XXX
+
+@subheading File:
+
+XXX
+
+@subheading Description:
+
+XXX
+
+
+@c
+@c
+@c
+@page
+
+@subsubsection evalformake Handler
+
+@subheading Corresponding Structure Element:
+
+XXX
+
+@subheading Arguments:
+
+XXX
+
+@subheading File:
+
+XXX
+
+@subheading Description:
+
+XXX
+
+
+@c
+@c
+@c
+@page
+
+@subsubsection link Handler
+
+@subheading Corresponding Structure Element:
+
+link
+
+@subheading Arguments:
+
+
+@example
+rtems_filesystem_location_info_t *to_loc, /* IN */
+rtems_filesystem_location_info_t *parent_loc, /* IN */
+const char *token /* IN */
+@end example
+
+@subheading File:
+
+imfs_link.c
+
+@subheading Description:
+
+
+This routine is used to create a hard-link.
+
+It will first examine the st_nlink count of the node that we are trying to.
+If the link count exceeds LINK_MAX an error will be returned.
+
+The name of the link will be normalized to remove extraneous separators from
+the end of the name.
+
+@c
+@c
+@c
+@page
+
+@subsubsection unlink Handler
+
+@subheading Corresponding Structure Element:
+
+XXX
+
+@subheading Arguments:
+
+XXX
+
+@subheading File:
+
+XXX
+
+@subheading Description:
+
+XXX
+
+
+@c
+@c
+@c
+@page
+
+@subsubsection node_type Handler
+
+@subheading Corresponding Structure Element:
+
+node_type()
+
+@subheading Arguments:
+
+@example
+rtems_filesystem_location_info_t *pathloc /* IN */
+@end example
+
+@subheading File:
+
+imfs_ntype.c
+
+@subheading Description:
+
+XXX
+
+@c
+@c
+@c
+@page
+
+@subsubsection mknod Handler
+
+@subheading Corresponding Structure Element:
+
+mknod()
+
+@subheading Arguments:
+
+@example
+const char *token, /* IN */
+mode_t mode, /* IN */
+dev_t dev, /* IN */
+rtems_filesystem_location_info_t *pathloc /* IN/OUT */
+@end example
+
+@subheading File:
+
+mknod.c
+
+@subheading Description:
+
+XXX
+
+@c
+@c
+@c
+@page
+
+@subsubsection rmnod Handler
+
+@subheading Corresponding Structure Element:
+
+XXX
+
+@subheading Arguments:
+
+XXX
+
+@subheading File:
+
+XXX
+
+@subheading Description:
+
+XXX
+
+
+@c
+@c
+@c
+@page
+
+@subsubsection chown Handler
+
+@subheading Corresponding Structure Element:
+
+chown()
+
+@subheading Arguments:
+
+@example
+rtems_filesystem_location_info_t *pathloc /* IN */
+uid_t owner /* IN */
+gid_t group /* IN */
+@end example
+
+@subheading File:
+
+imfs_chown.c
+
+@subheading Description:
+
+XXX
+
+@c
+@c
+@c
+@page
+
+@subsubsection freenod Handler
+
+@subheading Corresponding Structure Element:
+
+XXX
+
+@subheading Arguments:
+
+XXX
+
+@subheading File:
+
+XXX
+
+@subheading Description:
+
+XXX
+
+
+@c
+@c
+@c
+@page
+
+@subsubsection mount Handler
+
+@subheading Corresponding Structure Element:
+
+mount()
+
+@subheading Arguments:
+
+@example
+rtems_filesystem_mount_table_entry_t *mt_entry
+@end example
+
+@subheading File:
+
+mount.c
+
+@subheading Description:
+
+XXX
+
+@c
+@c
+@c
+@page
+
+@subsubsection fsmount_me Handler
+
+@subheading Corresponding Structure Element:
+
+XXX
+
+@subheading Arguments:
+
+@example
+rtems_filesystem_mount_table_entry_t *mt_entry
+@end example
+
+@subheading File:
+
+XXX
+
+@subheading Description:
+
+This function is provided with a filesystem to take care of the internal
+filesystem management details associated with mounting that filesystem
+under the RTEMS environment.
+
+It is not responsible for the mounting details associated the filesystem
+containing the mount point.
+
+The rtems_filesystem_mount_table_entry_t structure contains the key elements
+below:
+
+rtems_filesystem_location_info_t *mt_point_node,
+
+This structure contains information about the mount point. This
+allows us to find the ops-table and the handling functions
+associated with the filesystem containing the mount point.
+
+rtems_filesystem_location_info_t *fs_root_node,
+
+This structure contains information about the root node in the file
+system to be mounted. It allows us to find the ops-table and the
+handling functions associated with the filesystem to be mounted.
+
+rtems_filesystem_options_t options,
+
+Read only or read/write access
+
+void *fs_info,
+
+This points to an allocated block of memory the will be used to
+hold any filesystem specific information of a global nature. This
+allocated region if important because it allows us to mount the
+same filesystem type more than once under the RTEMS system.
+Each instance of the mounted filesystem has its own set of global
+management information that is separate from the global
+management information associated with the other instances of the
+mounted filesystem type.
+
+rtems_filesystem_limits_and_options_t pathconf_info,
+
+The table contains the following set of values associated with the
+mounted filesystem:
+
+@itemize @bullet
+
+@item link_max
+
+@item max_canon
+
+@item max_input
+
+@item name_max
+
+@item path_max
+
+@item pipe_buf
+
+@item posix_async_io
+
+@item posix_chown_restrictions
+
+@item posix_no_trunc
+
+@item posix_prio_io
+
+@item posix_sync_io
+
+@item posix_vdisable
+
+@end itemize
+
+These values are accessed with the pathconf() and the fpathconf ()
+functions.
+
+const char *dev
+
+The is intended to contain a string that identifies the device that contains
+the filesystem information. The filesystems that are currently implemented
+are memory based and don't require a device specification.
+
+If the mt_point_node.node_access is NULL then we are mounting the base file
+system.
+
+The routine will create a directory node for the root of the IMFS file
+system.
+
+The node will have read, write and execute permissions for owner, group and
+others.
+
+The node's name will be a null string.
+
+A filesystem information structure(fs_info) will be allocated and
+initialized for the IMFS filesystem. The fs_info pointer in the mount table
+entry will be set to point the filesystem information structure.
+
+The pathconf_info element of the mount table will be set to the appropriate
+table of path configuration constants (LIMITS_AND_OPTIONS).
+
+The fs_root_node structure will be filled in with the following:
+
+@itemize @bullet
+
+@item pointer to the allocated root node of the filesystem
+
+@item directory handlers for a directory node under the IMFS filesystem
+
+@item OPS table functions for the IMFS
+
+@end itemize
+
+A 0 will be returned to the calling routine if the process succeeded,
+otherwise a 1 will be returned.
+
+
+@c
+@c
+@c
+@page
+
+@subsubsection unmount Handler
+
+@subheading Corresponding Structure Element:
+
+XXX
+
+@subheading Arguments:
+
+XXX
+
+@subheading File:
+
+XXX
+
+@subheading Description:
+
+XXX
+
+
+@c
+@c
+@c
+@page
+
+@subsubsection fsunmount_me Handler
+
+@subheading Corresponding Structure Element:
+
+imfs_fsunmount_me()
+
+@subheading Arguments:
+
+@example
+rtems_filesystem_mount_table_entry_t *mt_entry
+@end example
+
+@subheading File:
+
+imfs_fsunmount_me.c
+
+@subheading Description:
+
+XXX
+
+
+@c
+@c
+@c
+@page
+
+@subsubsection utime Handler
+
+@subheading Corresponding Structure Element:
+
+XXX
+
+@subheading Arguments:
+
+XXX
+
+@subheading File:
+
+XXX
+
+@subheading Description:
+
+XXX
+
+@c
+@c
+@c
+@page
+
+@subsubsection eval_link Handler
+
+@subheading Corresponding Structure Element:
+
+XXX
+
+@subheading Arguments:
+
+XXX
+
+@subheading File:
+
+XXX
+
+@subheading Description:
+
+XXX
+
+@c
+@c
+@c
+@page
+
+@subsubsection symlink Handler
+
+@subheading Corresponding Structure Element:
+
+XXX
+
+@subheading Arguments:
+
+XXX
+
+@subheading File:
+
+XXX
+
+@subheading Description:
+
+XXX
+
+@c
+@c
+@c
+@page
+@subsection File Handler Table Functions
+
+Handler table functions are defined in a @code{rtems_filesystem_file_handlers_r}
+structure. It defines functions that are specific to a node type in a given
+filesystem. One table exists for each of the filesystem's node types. The
+structure definition appears below. It is followed by general developmental
+information on each of the functions associated with regular files contained
+in this function management structure.
+
+@example
+typedef struct @{
+ rtems_filesystem_open_t open;
+ rtems_filesystem_close_t close;
+ rtems_filesystem_read_t read;
+ rtems_filesystem_write_t write;
+ rtems_filesystem_ioctl_t ioctl;
+ rtems_filesystem_lseek_t lseek;
+ rtems_filesystem_fstat_t fstat;
+ rtems_filesystem_fchmod_t fchmod;
+ rtems_filesystem_ftruncate_t ftruncate;
+ rtems_filesystem_fpathconf_t fpathconf;
+ rtems_filesystem_fsync_t fsync;
+ rtems_filesystem_fdatasync_t fdatasync;
+ rtems_filesystem_fcntl_t fcntl;
+@} rtems_filesystem_file_handlers_r;
+@end example
+
+@c
+@c
+@c
+@page
+
+@subsubsection open Handler
+
+@subheading Corresponding Structure Element:
+
+open()
+
+@subheading Arguments:
+
+@example
+rtems_libio_t *iop,
+const char *pathname,
+unsigned32 flag,
+unsigned32 mode
+@end example
+
+@subheading File:
+
+XXX
+
+@subheading Description:
+
+XXX
+
+@c
+@c
+@c
+@page
+
+@subsubsection close Handler
+
+@subheading Corresponding Structure Element:
+
+close()
+
+@subheading Arguments:
+
+@example
+rtems_libio_t *iop
+@end example
+
+@subheading File:
+
+XXX
+
+@subheading Description:
+
+XXX
+
+@subheading NOTES:
+
+XXX
+
+
+
+@c
+@c
+@c
+@page
+
+@subsubsection read Handler
+
+@subheading Corresponding Structure Element:
+
+read()
+
+@subheading Arguments:
+
+@example
+rtems_libio_t *iop,
+void *buffer,
+unsigned32 count
+@end example
+
+@subheading File:
+
+XXX
+
+@subheading Description:
+
+XXX
+
+@subheading NOTES:
+
+XXX
+
+
+@c
+@c
+@c
+@page
+
+@subsubsection write Handler
+
+@subheading Corresponding Structure Element:
+
+XXX
+
+@subheading Arguments:
+
+XXX
+@subheading File:
+
+XXX
+
+@subheading Description:
+
+XXX
+
+@subheading NOTES:
+
+XXX
+
+
+@c
+@c
+@c
+@page
+
+@subsubsection ioctl Handler
+
+@subheading Corresponding Structure Element:
+
+XXX
+
+@subheading Arguments:
+
+@example
+rtems_libio_t *iop,
+unsigned32 command,
+void *buffer
+@end example
+
+@subheading File:
+
+XXX
+
+@subheading Description:
+
+XXX
+
+@subheading NOTES:
+
+XXX
+
+
+@c
+@c
+@c
+@page
+
+@subsubsection lseek Handler
+
+@subheading Corresponding Structure Element:
+
+lseek()
+
+@subheading Arguments:
+
+@example
+rtems_libio_t *iop,
+off_t offset,
+int whence
+@end example
+
+@subheading File:
+
+XXX
+
+@subheading Description:
+
+XXX
+
+@subheading NOTES:
+
+XXX
+
+
+@c
+@c
+@c
+@page
+
+@subsubsection fstat Handler
+
+@subheading Corresponding Structure Element:
+
+fstat()
+
+@subheading Arguments:
+
+@example
+rtems_filesystem_location_info_t *loc,
+struct stat *buf
+@end example
+
+@subheading File:
+
+XXX
+
+@subheading Description:
+
+The following information is extracted from the filesystem
+specific node and placed in the @code{stat} structure:
+
+@itemize @bullet
+
+@item st_mode
+
+@item st_nlink
+
+@item st_ino
+
+@item st_uid
+
+@item st_gid
+
+@item st_atime
+
+@item st_mtime
+
+@item st_ctime
+
+@end itemize
+
+
+@subheading NOTES:
+
+XXX
+
+@c
+@c
+@c
+@page
+
+@subsubsection fchmod Handler
+
+@subheading Corresponding Structure Element:
+
+fchmod()
+
+@subheading Arguments:
+
+@example
+rtems_libio_t *iop
+mode_t mode
+@end example
+
+@subheading File:
+
+imfs_fchmod.c
+
+@subheading Description:
+
+XXX
+
+
+@subheading NOTES:
+
+XXX
+
+@c
+@c
+@c
+@page
+
+@subsubsection ftruncate Handler
+
+@subheading Corresponding Structure Element:
+
+XXX
+
+@subheading Arguments:
+
+XXX
+@subheading File:
+
+XXX
+
+@subheading Description:
+
+XXX
+
+@subheading NOTES:
+
+XXX
+
+@subsubsection fpathconf Handler
+
+@subheading Corresponding Structure Element:
+
+XXX
+
+@subheading Arguments:
+
+XXX
+
+@subheading File:
+
+XXX
+
+@subheading Description:
+
+XXX
+
+@subheading NOTES:
+
+XXX
+
+@c
+@c
+@c
+@page
+
+@subsubsection fsync Handler
+
+@subheading Corresponding Structure Element:
+
+XXX
+
+@subheading Arguments:
+
+XXX
+@subheading File:
+
+XXX
+
+@subheading Description:
+
+XXX
+
+@subheading NOTES:
+
+XXX
+
+@c
+@c
+@c
+@page
+
+@subsubsection fdatasync Handler
+
+@subheading Corresponding Structure Element:
+
+XXX
+
+@subheading Arguments:
+
+XXX
+
+@subheading File:
+
+XXX
+
+@subheading Description:
+
+XXX
+
+@subheading NOTES:
+
+XXX
+
+@c
+@c
+@c
+@page
+
+@subsubsection fcntl Handler
+
+@subheading Corresponding Structure Element:
+
+XXX
+
+@subheading Arguments:
+
+XXX
+
+@subheading File:
+
+XXX
+
+@subheading Description:
+
+XXX
+
+@subheading NOTES:
+
+XXX
diff --git a/doc/filesystem/imfs.t b/doc/filesystem/imfs.t
index 3a0362f957..eb96ef1266 100644
--- a/doc/filesystem/imfs.t
+++ b/doc/filesystem/imfs.t
@@ -1,49 +1,215 @@
+@c COPYRIGHT (c) 1988-1998.
+@c On-Line Applications Research Corporation (OAR).
+@c All rights reserved.
+@c
+@c $Id$
+@c
@chapter In-Memory Filesystem
-This chapter describes the In-Memory Filesystem.
+This chapter describes the In-Memory Filesystem (IMFS). The IMFS is a
+full featured POSIX filesystem that keeps all information in memory.
+
+@section IMFS Per Node Data Structure
+
+Each regular file, device, hard link, and directory is represented by a data
+structure called a @code{jnode}. The @code{jnode} is formally represented by the
+structure:
+
+@example
+struct IMFS_jnode_tt @{
+ Chain_Node Node; /* for chaining them together */
+ IMFS_jnode_t *Parent; /* Parent node */
+ char name[NAME_MAX+1]; /* "basename" */
+ mode_t st_mode; /* File mode */
+ nlink_t st_nlink; /* Link count */
+ ino_t st_ino; /* inode */
+
+ uid_t st_uid; /* User ID of owner */
+ gid_t st_gid; /* Group ID of owner */
+ time_t st_atime; /* Time of last access */
+ time_t st_mtime; /* Time of last modification */
+ time_t st_ctime; /* Time of last status change */
+ IMFS_jnode_types_t type; /* Type of this entry */
+ IMFS_typs_union info;
+@};
+@end example
+
+The key elements of this structure are listed below together with a brief
+explanation of their role in the filesystem.
+
+@table @b
+
+@item Node
+exists to allow the entire @code{jnode} structure to be included in a chain.
+
+@item Parent
+is a pointer to another @code{jnode} structure that is the logical parent of the
+node in which it appears. This field may be NULL if the file associated with
+this node is deleted but there are open file descriptors on this file or
+there are still hard links to this node.
+
+@item name
+is the name of this node within the filesystem hierarchical tree. Example: If
+the fully qualified pathname to the @code{jnode} was @code{/a/b/c}, the
+@code{jnode} name field would contain the null terminated string @code{"c"}.
+
+@item st_mode
+is the standard Unix access permissions for the file or directory.
+
+@item st_nlink
+is the number of hard links to this file. When a @code{jnode} is first created
+its link count is set to 1. A @code{jnode} and its associated resources
+cannot be deleted unless its link count is less than 1.
+
+@item st_ino
+is a unique node identification number
+
+@item st_uid
+is the user ID of the file's owner
+
+@item st_gid
+is the group ID of the file's owner
+
+@item st_atime
+is the time of the last access to this file
+
+@item st_mtime
+is the time of the last modification of this file
+
+@item st_ctime
+is the time of the last status change to the file
+
+@item type
+is the indication of node type must be one of the following states:
+
+@itemize @bullet
+@item IMFS_DIRECTORY
+@item IMFS_MEMORY_FILE
+@item IMFS_HARD_LINK
+@item IMFS_SYM_LINK
+@item IMFS_DEVICE
+@end itemize
+
-@section Filesystem Handler Table Functions
+@item info
+is this contains a structure that is unique to file type (See IMFS_typs_union
+in imfs.h).
+
+@itemize @bullet
+
+@item IMFS_DIRECTORY
+
+An IMFS directory contains a dynamic chain structure that
+records all files and directories that are subordinate to the directory node.
+
+@item IMFS_MEMORY_FILE
+
+Under the in memory filesystem regular files hold data. Data is dynamically
+allocated to the file in 128 byte chunks of memory. The individual chunks of
+memory are tracked by arrays of pointers that record the address of the
+allocated chunk of memory. Single, double, and triple indirection pointers
+are used to record the locations of all segments of the file. The
+memory organization of an IMFS file are discussed elsewhere in this manual.
+
+@item IMFS_HARD_LINK
+
+The IMFS filesystem supports the concept of hard links to other nodes in the
+IMFS filesystem. These hard links are actual pointers to other nodes in the
+same filesystem. This type of link cannot cross-filesystem boundaries.
+
+@item IMFS_SYM_LINK
+
+The IMFS filesystem supports the concept of symbolic links to other nodes in
+any filesystem. A symbolic link consists of a pointer to a character string
+that represents the pathname to the target node. This type of link can
+cross-filesystem boundaries. Just as with most versions of UNIX supporting
+symbolic links, a symbolic link can point to a non-existent file.
+
+@item IMFS_DEVICE
+
+All RTEMS devices now appear as files under the in memory filesystem. On
+system initialization, all devices are registered as nodes under the file
+system.
+
+@end itemize
+
+@end table
+
+@section Miscellaneous IMFS Information
+
+@section Memory associated with the IMFS
+
+A memory based filesystem draws its resources for files and directories
+from the memory resources of the system. When it is time to un-mount the
+filesystem, the memory resources that supported filesystem are set free.
+In order to free these resources, a recursive walk of the filesystems
+tree structure will be performed. As the leaf nodes under the filesystem
+are encountered their resources are freed. When directories are made empty
+by this process, their resources are freed.
+
+@subsection Node removal constraints for the IMFS
+
+The IMFS conforms to the general filesystem requirements for node
+removal. See @ref{File and Directory Removal Constraints}.
+
+@subsection IMFS General Housekeeping Notes
+
+The following is a list of odd housekeeping notes for the IMFS.
+
+@itemize @bullet
+
+@item If the global variable rtems_filesystem_current refers to the node that
+we are trying to remove, the node_access element of this structure must be
+set to NULL to invalidate it.
+
+@item If the node was of IMFS_MEMORY_FILE type, free the memory associated
+with the memory file before freeing the node. Use the IMFS_memfile_remove()
+function.
+
+@end itemize
+
+@section IMFS Operation Tables
+
+@subsection IMFS Filesystem Handler Table Functions
OPS table functions are defined in a rtems_filesystem_operations_table
-structure. It defines functions that are specific to a given file system.
-One table exists for each file system that is supported in the RTEMS
+structure. It defines functions that are specific to a given filesystem.
+One table exists for each filesystem that is supported in the RTEMS
configuration. The structure definition appears below and is followed by
general developmental information on each of the functions contained in this
function management structure.
@example
-typedef struct @{
- rtems_filesystem_evalpath_t evalpath;
- rtems_filesystem_evalmake_t evalformake;
- rtems_filesystem_link_t link;
- rtems_filesystem_unlink_t unlink;
- rtems_filesystem_node_type_t node_type;
- rtems_filesystem_mknod_t mknod;
- rtems_filesystem_rmnod_t rmnod;
- rtems_filesystem_chown_t chown;
- rtems_filesystem_freenode_t freenod;
- rtems_filesystem_mount_t mount;
- rtems_filesystem_fsmount_me_t fsmount_me;
- rtems_filesystem_unmount_t unmount;
- rtems_filesystem_fsunmount_me_t fsunmount_me;
- rtems_filesystem_utime_t utime;
- rtems_filesystem_evaluate_link_t eval_link;
- rtems_filesystem_symlink_t symlink;
-@} rtems_filesystem_operations_table;
+rtems_filesystem_operations_table IMFS_ops = @{
+ IMFS_eval_path,
+ IMFS_evaluate_for_make,
+ IMFS_link,
+ IMFS_unlink,
+ IMFS_node_type,
+ IMFS_mknod,
+ IMFS_rmnod,
+ IMFS_chown,
+ IMFS_freenodinfo,
+ IMFS_mount,
+ IMFS_initialize,
+ IMFS_unmount,
+ IMFS_fsunmount,
+ IMFS_utime,
+ IMFS_evaluate_link,
+ IMFS_symlink,
+ IMFS_readlink
+@};
@end example
-
-
@c
@c
@c
-
@page
-@subsection evalpath()
+@subsubsection IMFS_evalpath()
-@subheading Slot Function:
+@subheading Corresponding Structure Element:
XXX
@@ -55,7 +221,7 @@ XXX
XXX
-@subheading Development Comments:
+@subheading Description:
XXX
@@ -63,12 +229,11 @@ XXX
@c
@c
@c
-
@page
-@subsection evalformake()
+@subsubsection IMFS_evalformake()
-@subheading Slot Function:
+@subheading Corresponding Structure Element:
XXX
@@ -80,7 +245,7 @@ XXX
XXX
-@subheading Development Comments:
+@subheading Description:
XXX
@@ -88,12 +253,11 @@ XXX
@c
@c
@c
-
@page
-@subsection link()
+@subsubsection IMFS_link()
-@subheading Slot Function:
+@subheading Corresponding Structure Element:
link
@@ -110,10 +274,10 @@ const char *token /* IN */
imfs_link.c
-@subheading Development Comments:
+@subheading Description:
-This routine is used in the IMFS file system to create a hard-link.
+This routine is used in the IMFS filesystem to create a hard-link.
It will first examine the st_nlink count of the node that we are trying to.
If the link count exceeds LINK_MAX an error will be returned.
@@ -121,7 +285,7 @@ If the link count exceeds LINK_MAX an error will be returned.
The name of the link will be normalized to remove extraneous separators from
the end of the name.
-IMFS_create_node will be used to create a file system node that will have the
+IMFS_create_node will be used to create a filesystem node that will have the
following characteristics:
@itemize @bullet
@@ -146,13 +310,14 @@ The time fields of the link will be set to reflect the creation time of the
hard-link.
-@c @c @c
-
+@c
+@c
+@c
@page
-@subsection unlink()
+@subsubsection IMFS_unlink()
-@subheading Slot Function:
+@subheading Corresponding Structure Element:
XXX
@@ -164,7 +329,7 @@ XXX
XXX
-@subheading Development Comments:
+@subheading Description:
XXX
@@ -172,12 +337,11 @@ XXX
@c
@c
@c
-
@page
-@subsection node_type()
+@subsubsection IMFS_node_type()
-@subheading Slot Function:
+@subheading Corresponding Structure Element:
IMFS_node_type()
@@ -191,10 +355,10 @@ rtems_filesystem_location_info_t *pathloc /* IN */
imfs_ntype.c
-@subheading Development Comments:
+@subheading Description:
This routine will locate the IMFS_jnode_t structure that holds ownership
-information for the selected node in the file system.
+information for the selected node in the filesystem.
This structure is pointed to by pathloc->node_access.
@@ -215,12 +379,11 @@ The IMFS_jnode_t type element indicates one of the node types listed below:
@c
@c
@c
-
@page
-@subsection mknod()
+@subsubsection IMFS_mknod()
-@subheading Slot Function:
+@subheading Corresponding Structure Element:
IMFS_mknod()
@@ -237,7 +400,7 @@ rtems_filesystem_location_info_t *pathloc /* IN/OUT */
imfs_mknod.c
-@subheading Development Comments:
+@subheading Description:
This routine will examine the mode argument to determine is we are trying to
create a directory, regular file and a device node. The creation of other
@@ -254,12 +417,11 @@ attempt to allocate space for the @code{jnode} (ENOMEN).
@c
@c
@c
-
@page
-@subsection rmnod()
+@subsubsection IMFS_rmnod()
-@subheading Slot Function:
+@subheading Corresponding Structure Element:
XXX
@@ -271,7 +433,7 @@ XXX
XXX
-@subheading Development Comments:
+@subheading Description:
XXX
@@ -279,12 +441,11 @@ XXX
@c
@c
@c
-
@page
-@subsection chown()
+@subsubsection IMFS_chown()
-@subheading Slot Function:
+@subheading Corresponding Structure Element:
IMFS_chown()
@@ -300,15 +461,15 @@ gid_t group /* IN */
imfs_chown.c
-@subheading Development Comments:
+@subheading Description:
This routine will locate the IMFS_jnode_t structure that holds ownership
-information for the selected node in the file system.
+information for the selected node in the filesystem.
This structure is pointed to by pathloc->node_access.
The st_uid and st_gid fields of the node are then modified. Since this is a
-memory based file system, no further action is required to alter the
+memory based filesystem, no further action is required to alter the
ownership of the IMFS_jnode_t structure.
@@ -316,12 +477,11 @@ ownership of the IMFS_jnode_t structure.
@c
@c
@c
-
@page
-@subsection freenod()
+@subsubsection IMFS_freenod()
-@subheading Slot Function:
+@subheading Corresponding Structure Element:
XXX
@@ -333,7 +493,7 @@ XXX
XXX
-@subheading Development Comments:
+@subheading Description:
XXX
@@ -341,12 +501,11 @@ XXX
@c
@c
@c
-
@page
-@subsection mount()
+@subsubsection IMFS_mount()
-@subheading Slot Function:
+@subheading Corresponding Structure Element:
IMFS_mount()
@@ -360,32 +519,31 @@ rtems_filesystem_mount_table_entry_t *mt_entry
imfs_mount.c
-@subheading Development Comments:
+@subheading Description:
-This routine provides the file system specific processing required to mount a
-file system for the system that contains the mount point. It will determine
+This routine provides the filesystem specific processing required to mount a
+filesystem for the system that contains the mount point. It will determine
if the point that we are trying to mount onto is a node of IMFS_DIRECTORY
type.
If it is the node's info element is altered so that the info.directory.mt_fs
element points to the mount table chain entry that is associated with the
-mounted file system at this point. The info.directory.mt_fs element can be
-examined to determine if a file system is mounted at a directory. If it is
+mounted filesystem at this point. The info.directory.mt_fs element can be
+examined to determine if a filesystem is mounted at a directory. If it is
NULL, the directory does not serve as a mount point. A non-NULL entry
indicates that the directory does serve as a mount point and the value of
info.directory.mt_fs can be used to locate the mount table chain entry that
-describes the file system mounted at this point.
+describes the filesystem mounted at this point.
@c
@c
@c
-
@page
-@subsection fsmount_me()
+@subsubsection IMFS_fsmount_me()
-@subheading Slot Function:
+@subheading Corresponding Structure Element:
IMFS_initialize()
@@ -399,13 +557,13 @@ rtems_filesystem_mount_table_entry_t *mt_entry
imfs_init.c
-@subheading Development Comments:
+@subheading Description:
-This function is provided with a file system to take care of the internal
-file system management details associated with mounting that file system
+This function is provided with a filesystem to take care of the internal
+filesystem management details associated with mounting that filesystem
under the RTEMS environment.
-It is not responsible for the mounting details associated the file system
+It is not responsible for the mounting details associated the filesystem
containing the mount point.
The rtems_filesystem_mount_table_entry_t structure contains the key elements
@@ -415,13 +573,13 @@ rtems_filesystem_location_info_t *mt_point_node,
This structure contains information about the mount point. This
allows us to find the ops-table and the handling functions
-associated with the file system containing the mount point.
+associated with the filesystem containing the mount point.
rtems_filesystem_location_info_t *fs_root_node,
This structure contains information about the root node in the file
system to be mounted. It allows us to find the ops-table and the
-handling functions associated with the file system to be mounted.
+handling functions associated with the filesystem to be mounted.
rtems_filesystem_options_t options,
@@ -430,18 +588,18 @@ Read only or read/write access
void *fs_info,
This points to an allocated block of memory the will be used to
-hold any file system specific information of a global nature. This
+hold any filesystem specific information of a global nature. This
allocated region if important because it allows us to mount the
-same file system type more than once under the RTEMS system.
-Each instance of the mounted file system has its own set of global
+same filesystem type more than once under the RTEMS system.
+Each instance of the mounted filesystem has its own set of global
management information that is separate from the global
management information associated with the other instances of the
-mounted file system type.
+mounted filesystem type.
rtems_filesystem_limits_and_options_t pathconf_info,
The table contains the following set of values associated with the
-mounted file system:
+mounted filesystem:
@itemize @bullet
@@ -477,7 +635,7 @@ functions.
const char *dev
The is intended to contain a string that identifies the device that contains
-the file system information. The file systems that are currently implemented
+the filesystem information. The filesystems that are currently implemented
are memory based and don't require a device specification.
If the mt_point_node.node_access is NULL then we are mounting the base file
@@ -491,9 +649,9 @@ others.
The node's name will be a null string.
-A file system information structure(fs_info) will be allocated and
-initialized for the IMFS file system. The fs_info pointer in the mount table
-entry will be set to point the file system information structure.
+A filesystem information structure(fs_info) will be allocated and
+initialized for the IMFS filesystem. The fs_info pointer in the mount table
+entry will be set to point the filesystem information structure.
The pathconf_info element of the mount table will be set to the appropriate
table of path configuration constants ( IMFS_LIMITS_AND_OPTIONS ).
@@ -502,9 +660,9 @@ The fs_root_node structure will be filled in with the following:
@itemize @bullet
-@item pointer to the allocated root node of the file system
+@item pointer to the allocated root node of the filesystem
-@item directory handlers for a directory node under the IMFS file system
+@item directory handlers for a directory node under the IMFS filesystem
@item OPS table functions for the IMFS
@@ -517,12 +675,11 @@ otherwise a 1 will be returned.
@c
@c
@c
-
@page
-@subsection unmount()
+@subsubsection IMFS_unmount()
-@subheading Slot Function:
+@subheading Corresponding Structure Element:
XXX
@@ -534,7 +691,7 @@ XXX
XXX
-@subheading Development Comments:
+@subheading Description:
XXX
@@ -542,12 +699,11 @@ XXX
@c
@c
@c
-
@page
-@subsection fsunmount_me()
+@subsubsection IMFS_fsunmount_me()
-@subheading Slot Function:
+@subheading Corresponding Structure Element:
imfs_fsunmount_me()
@@ -561,7 +717,7 @@ rtems_filesystem_mount_table_entry_t *mt_entry
imfs_fsunmount_me.c
-@subheading Development Comments:
+@subheading Description:
XXX
@@ -569,12 +725,11 @@ XXX
@c
@c
@c
-
@page
-@subsection utime()
+@subsubsection IMFS_utime()
-@subheading Slot Function:
+@subheading Corresponding Structure Element:
XXX
@@ -586,7 +741,7 @@ XXX
XXX
-@subheading Development Comments:
+@subheading Description:
XXX
@@ -594,12 +749,11 @@ XXX
@c
@c
@c
-
@page
-@subsection eval_link()
+@subsubsection IMFS_eval_link()
-@subheading Slot Function:
+@subheading Corresponding Structure Element:
XXX
@@ -611,7 +765,7 @@ XXX
XXX
-@subheading Development Comments:
+@subheading Description:
XXX
@@ -619,42 +773,42 @@ XXX
@c
@c
@page
-@section Regular File Handler Table Functions
+@subsection Regular File Handler Table Functions
Handler table functions are defined in a rtems_filesystem_file_handlers_r
structure. It defines functions that are specific to a node type in a given
-file system. One table exists for each of the file system's node types. The
+filesystem. One table exists for each of the filesystem's node types. The
structure definition appears below. It is followed by general developmental
information on each of the functions associated with regular files contained
in this function management structure.
@example
-typedef struct @{
- rtems_filesystem_open_t open;
- rtems_filesystem_close_t close;
- rtems_filesystem_read_t read;
- rtems_filesystem_write_t write;
- rtems_filesystem_ioctl_t ioctl;
- rtems_filesystem_lseek_t lseek;
- rtems_filesystem_fstat_t fstat;
- rtems_filesystem_fchmod_t fchmod;
- rtems_filesystem_ftruncate_t ftruncate;
- rtems_filesystem_fpathconf_t fpathconf;
- rtems_filesystem_fsync_t fsync;
- rtems_filesystem_fdatasync_t fdatasync;
-@} rtems_filesystem_file_handlers_r;
+rtems_filesystem_file_handlers_r IMFS_memfile_handlers = @{
+ memfile_open,
+ memfile_close,
+ memfile_read,
+ memfile_write,
+ memfile_ioctl,
+ memfile_lseek,
+ IMFS_stat,
+ IMFS_fchmod,
+ memfile_ftruncate,
+ NULL, /* fpathconf */
+ NULL, /* fsync */
+ IMFS_fdatasync,
+ IMFS_fcntl
+@};
@end example
@c
@c
@c
-
@page
-@subsection open() for Regular Files
+@subsubsection memfile_open() for Regular Files
-@subheading Slot Function:
+@subheading Corresponding Structure Element:
memfile_open()
@@ -671,7 +825,7 @@ unsigned32 mode
memfile.c
-@subheading Development Comments:
+@subheading Description:
Currently this function is a shell. No meaningful processing is performed and
a success code is always returned.
@@ -679,12 +833,11 @@ a success code is always returned.
@c
@c
@c
-
@page
-@subsection close() for Regular Files
+@subsubsection memfile_close() for Regular Files
-@subheading Slot Function:
+@subheading Corresponding Structure Element:
memfile_close()
@@ -698,9 +851,9 @@ rtems_libio_t *iop
memfile.c
-@subheading Development Comments:
+@subheading Description:
-This routine is a dummy for regular files under the base file system. It
+This routine is a dummy for regular files under the base filesystem. It
performs a capture of the IMFS_jnode_t pointer from the file control block
and then immediately returns a success status.
@@ -708,12 +861,11 @@ and then immediately returns a success status.
@c
@c
@c
-
@page
-@subsection read() for Regular Files
+@subsubsection memfile_read() for Regular Files
-@subheading Slot Function:
+@subheading Corresponding Structure Element:
memfile_read()
@@ -729,7 +881,7 @@ unsigned32 count
memfile.c
-@subheading Development Comments:
+@subheading Description:
This routine will determine the @code{jnode} that is associated with this file.
@@ -755,12 +907,11 @@ IMFS_memfile_read() will do the following:
@c
@c
@c
-
@page
-@subsection write() for Regular Files
+@subsubsection memfile_write() for Regular Files
-@subheading Slot Function:
+@subheading Corresponding Structure Element:
XXX
@@ -771,19 +922,18 @@ XXX
XXX
-@subheading Development Comments:
+@subheading Description:
XXX
@c
@c
@c
-
@page
-@subsection ioctl() for Regular Files
+@subsubsection memfile_ioctl() for Regular Files
-@subheading Slot Function:
+@subheading Corresponding Structure Element:
XXX
@@ -799,7 +949,7 @@ void *buffer
memfile.c
-@subheading Development Comments:
+@subheading Description:
The current code is a placeholder for future development. The routine returns
a successful completion status.
@@ -807,12 +957,11 @@ a successful completion status.
@c
@c
@c
-
@page
-@subsection lseek() for Regular Files
+@subsubsection memfile_lseek() for Regular Files
-@subheading Slot Function:
+@subheading Corresponding Structure Element:
Memfile_lseek()
@@ -828,7 +977,7 @@ int whence
memfile.c
-@subheading Development Comments:
+@subheading Description:
This routine make sure that the memory based file is sufficiently large to
allow for the new file position index.
@@ -840,12 +989,11 @@ file position index. A success code is always returned from this routine.
@c
@c
@c
-
@page
-@subsection fstat() for Regular Files
+@subsubsection IMFS_stat() for Regular Files
-@subheading Slot Function:
+@subheading Corresponding Structure Element:
IMFS_stat()
@@ -860,13 +1008,13 @@ struct stat *buf
imfs_stat.c
-@subheading Development Comments:
+@subheading Description:
This routine actually performs status processing for both devices and regular
files.
The IMFS_jnode_t structure is referenced to determine the type of node under
-the file system.
+the filesystem.
If the node is associated with a device, node information is extracted and
transformed to set the st_dev element of the stat structure.
@@ -902,12 +1050,11 @@ structure:
@c
@c
@c
-
@page
-@subsection fchmod() for Regular Files
+@subsubsection IMFS_fchmod() for Regular Files
-@subheading Slot Function:
+@subheading Corresponding Structure Element:
IMFS_fchmod()
@@ -922,7 +1069,7 @@ mode_t mode
imfs_fchmod.c
-@subheading Development Comments:
+@subheading Description:
This routine will obtain the pointer to the IMFS_jnode_t structure from the
information currently in the file control block.
@@ -943,12 +1090,11 @@ based on the mode calling parameter.
@c
@c
@c
-
@page
-@subsection ftruncate() for Regular Files
+@subsubsection memfile_ftruncate() for Regular Files
-@subheading Slot Function:
+@subheading Corresponding Structure Element:
XXX
@@ -959,19 +1105,14 @@ XXX
XXX
-@subheading Development Comments:
+@subheading Description:
XXX
-@c
-@c
-@c
-
-@page
-@subsection fpathconf() for Regular Files
+@subsubsection No pathconf() for Regular Files
-@subheading Slot Function:
+@subheading Corresponding Structure Element:
NULL
@@ -983,7 +1124,7 @@ Not Implemented
Not Implemented
-@subheading Development Comments:
+@subheading Description:
Not Implemented
@@ -991,12 +1132,11 @@ Not Implemented
@c
@c
@c
-
@page
-@subsection fsync() for Regular Files
+@subsubsection No fsync() for Regular Files
-@subheading Slot Function:
+@subheading Corresponding Structure Element:
XXX
@@ -1007,7 +1147,7 @@ XXX
XXX
-@subheading Development Comments:
+@subheading Description:
XXX
@@ -1015,12 +1155,11 @@ XXX
@c
@c
@c
-
@page
-@subsection fdatasync() for Regular Files
+@subsubsection IMFS_fdatasync() for Regular Files
-@subheading Slot Function:
+@subheading Corresponding Structure Element:
XXX
@@ -1031,7 +1170,7 @@ XXX
XXX
-@subheading Development Comments:
+@subheading Description:
XXX
@@ -1039,42 +1178,41 @@ XXX
@c
@c
@page
-@section Directory Handler Table Functions
+@subsection Directory Handler Table Functions
Handler table functions are defined in a rtems_filesystem_file_handlers_r
structure. It defines functions that are specific to a node type in a given
-file system. One table exists for each of the file system's node types. The
+filesystem. One table exists for each of the filesystem's node types. The
structure definition appears below. It is followed by general developmental
information on each of the functions associated with directories contained in
this function management structure.
@example
-typedef struct @{
- rtems_filesystem_open_t open;
- rtems_filesystem_close_t close;
- rtems_filesystem_read_t read;
- rtems_filesystem_write_t write;
- rtems_filesystem_ioctl_t ioctl;
- rtems_filesystem_lseek_t lseek;
- rtems_filesystem_fstat_t fstat;
- rtems_filesystem_fchmod_t fchmod;
- rtems_filesystem_ftruncate_t ftruncate;
- rtems_filesystem_fpathconf_t fpathconf;
- rtems_filesystem_fsync_t fsync;
- rtems_filesystem_fdatasync_t fdatasync;
-@} rtems_filesystem_file_handlers_r;
+rtems_filesystem_file_handlers_r IMFS_directory_handlers = @{
+ IMFS_dir_open,
+ IMFS_dir_close,
+ IMFS_dir_read,
+ NULL, /* write */
+ NULL, /* ioctl */
+ IMFS_dir_lseek,
+ IMFS_dir_fstat,
+ IMFS_fchmod,
+ NULL, /* ftruncate */
+ NULL, /* fpathconf */
+ NULL, /* fsync */
+ IMFS_fdatasync,
+ IMFS_fcntl
+@};
@end example
@c
@c
@c
-
@page
+@subsubsection IMFS_dir_open() for Directories
-@subsection open() for Directories
-
-@subheading Slot Function:
+@subheading Corresponding Structure Element:
imfs_dir_open()
@@ -1091,7 +1229,7 @@ unsigned32 mode
imfs_directory.c
-@subheading Development Comments:
+@subheading Description:
This routine will look into the file control block to find the @code{jnode} that
is associated with the directory.
@@ -1105,12 +1243,11 @@ This allows us to start reading at the beginning of the directory.
@c
@c
@c
-
@page
-@subsection close() for Directories
+@subsubsection IMFS_dir_close() for Directories
-@subheading Slot Function:
+@subheading Corresponding Structure Element:
imfs_dir_close()
@@ -1124,20 +1261,19 @@ rtems_libio_t *iop
imfs_directory.c
-@subheading Development Comments:
+@subheading Description:
-This routine is a dummy for directories under the base file system. It
+This routine is a dummy for directories under the base filesystem. It
immediately returns a success status.
@c
@c
@c
-
@page
-@subsection read() for Directories
+@subsubsection IMFS_dir_read() for Directories
-@subheading Slot Function:
+@subheading Corresponding Structure Element:
imfs_dir_read
@@ -1153,7 +1289,7 @@ unsigned32 count
imfs_directory.c
-@subheading Development Comments:
+@subheading Description:
This routine will read a fixed number of directory entries from the current
directory offset. The number of directory bytes read will be returned from
@@ -1163,12 +1299,11 @@ this routine.
@c
@c
@c
-
@page
-@subsection write() for Directories
+@subsubsection No write() for Directories
-@subheading Slot Function:
+@subheading Corresponding Structure Element:
XXX
@@ -1180,19 +1315,18 @@ XXX
XXX
-@subheading Development Comments:
+@subheading Description:
XXX
@c
@c
@c
-
@page
-@subsection ioctl() for Directories
+@subsubsection No ioctl() for Directories
-@subheading Slot Function:
+@subheading Corresponding Structure Element:
ioctl
@@ -1203,19 +1337,18 @@ ioctl
Not supported
-@subheading Development Comments:
+@subheading Description:
XXX
@c
@c
@c
-
@page
-@subsection lseek() for Directories
+@subsubsection IMFS_dir_lseek() for Directories
-@subheading Slot Function:
+@subheading Corresponding Structure Element:
imfs_dir_lseek()
@@ -1231,7 +1364,7 @@ int whence
imfs_directory.c
-@subheading Development Comments:
+@subheading Description:
This routine alters the offset in the file control block.
@@ -1244,12 +1377,11 @@ the open directory.
@c
@c
@c
-
@page
-@subsection fstat() for Directories
+@subsubsection IMFS_dir_fstat() for Directories
-@subheading Slot Function:
+@subheading Corresponding Structure Element:
imfs_dir_fstat()
@@ -1265,7 +1397,7 @@ struct stat *buf
imfs_directory.c
-@subheading Development Comments:
+@subheading Description:
The node access information in the rtems_filesystem_location_info_t structure
is used to locate the appropriate IMFS_jnode_t structure. The following
@@ -1290,12 +1422,11 @@ of the children of the directory.
@c
@c
@c
-
@page
-@subsection fchmod() for Directories
+@subsubsection IMFS_fchmod() for Directories
-@subheading Slot Function:
+@subheading Corresponding Structure Element:
IMFS_fchmod()
@@ -1310,7 +1441,7 @@ mode_t mode
imfs_fchmod.c
-@subheading Development Comments:
+@subheading Description:
This routine will obtain the pointer to the IMFS_jnode_t structure from the
information currently in the file control block.
@@ -1331,12 +1462,11 @@ based on the mode calling parameter.
@c
@c
@c
-
@page
-@subsection ftruncate() for Directories
+@subsubsection No ftruncate() for Directories
-@subheading Slot Function:
+@subheading Corresponding Structure Element:
XXX
@@ -1348,19 +1478,18 @@ XXX
XXX
-@subheading Development Comments:
+@subheading Description:
XXX
@c
@c
@c
-
@page
-@subsection fpathconf() for Directories
+@subsubsection No fpathconf() for Directories
-@subheading Slot Function:
+@subheading Corresponding Structure Element:
fpathconf
@@ -1372,7 +1501,7 @@ Not Implemented
Not Implemented
-@subheading Development Comments:
+@subheading Description:
Not Implemented
@@ -1380,12 +1509,11 @@ Not Implemented
@c
@c
@c
-
@page
-@subsection fsync() for Directories
+@subsubsection No fsync() for Directories
-@subheading Slot Function:
+@subheading Corresponding Structure Element:
XXX
@@ -1396,7 +1524,7 @@ XXX
XXX
-@subheading Development Comments:
+@subheading Description:
XXX
@@ -1404,12 +1532,11 @@ XXX
@c
@c
@c
-
@page
-@subsection fdatasync() for Directories
+@subsubsection IMFS_fdatasync() for Directories
-@subheading Slot Function:
+@subheading Corresponding Structure Element:
XXX
@@ -1421,16 +1548,19 @@ XXX
XXX
-@subheading Development Comments:
+@subheading Description:
XXX
-
-@section Device Handler Table Functions
+@c
+@c
+@c
+@page
+@subsection Device Handler Table Functions
Handler table functions are defined in a rtems_filesystem_file_handlers_r
structure. It defines functions that are specific to a node type in a given
-file system. One table exists for each of the file system's node types. The
+filesystem. One table exists for each of the filesystem's node types. The
structure definition appears below. It is followed by general developmental
information on each of the functions associated with devices contained in
this function management structure.
@@ -1455,12 +1585,11 @@ typedef struct @{
@c
@c
@c
-
@page
-@subsection open() for Devices
+@subsubsection device_open() for Devices
-@subheading Slot Function:
+@subheading Corresponding Structure Element:
device_open()
@@ -1477,7 +1606,7 @@ unsigned32 mode
deviceio.c
-@subheading Development Comments:
+@subheading Description:
This routine will use the file control block to locate the node structure for
the device.
@@ -1491,12 +1620,11 @@ driver that contains the file control block, flags and mode information.
@c
@c
@c
-
@page
-@subsection close() for Devices
+@subsubsection device_close() for Devices
-@subheading Slot Function:
+@subheading Corresponding Structure Element:
device_close()
@@ -1510,7 +1638,7 @@ rtems_libio_t *iop
deviceio.c
-@subheading Development Comments:
+@subheading Description:
This routine extracts the major and minor device driver numbers from the
IMFS_jnode_t that is referenced in the file control block.
@@ -1524,12 +1652,11 @@ major and minor device numbers.
@c
@c
@c
-
@page
-@subsection read() for Devices
+@subsubsection device_read() for Devices
-@subheading Slot Function:
+@subheading Corresponding Structure Element:
device_read()
@@ -1545,7 +1672,7 @@ unsigned32 count
deviceio.c
-@subheading Development Comments:
+@subheading Description:
This routine will extract the major and minor numbers for the device from the -
jnode- associated with the file descriptor.
@@ -1575,12 +1702,11 @@ read will be returned to the calling program.
@c
@c
@c
-
@page
-@subsection write() for Devices
+@subsubsection device_write() for Devices
-@subheading Slot Function:
+@subheading Corresponding Structure Element:
XXX
@@ -1591,19 +1717,18 @@ XXX
XXX
-@subheading Development Comments:
+@subheading Description:
XXX
@c
@c
@c
-
@page
-@subsection ioctl() for Devices
+@subsubsection device_ioctl() for Devices
-@subheading Slot Function:
+@subheading Corresponding Structure Element:
ioctl
@@ -1619,7 +1744,7 @@ void *buffer
deviceio.c
-@subheading Development Comments:
+@subheading Description:
This handler will obtain status information about a device.
@@ -1644,12 +1769,11 @@ the calling program, otherwise the ioctl_return value is returned.
@c
@c
@c
-
@page
-@subsection lseek() for Devices
+@subsubsection device_lseek() for Devices
-@subheading Slot Function:
+@subheading Corresponding Structure Element:
device_lseek()
@@ -1665,7 +1789,7 @@ int whence
deviceio.c
-@subheading Development Comments:
+@subheading Description:
At the present time this is a placeholder function. It always returns a
successful status.
@@ -1673,12 +1797,11 @@ successful status.
@c
@c
@c
-
@page
-@subsection fstat() for Devices
+@subsubsection IMFS_stat() for Devices
-@subheading Slot Function:
+@subheading Corresponding Structure Element:
IMFS_stat()
@@ -1693,12 +1816,12 @@ struct stat *buf
imfs_stat.c
-@subheading Development Comments:
+@subheading Description:
This routine actually performs status processing for both devices and regular files.
The IMFS_jnode_t structure is referenced to determine the type of node under the
-file system.
+filesystem.
If the node is associated with a device, node information is extracted and
transformed to set the st_dev element of the stat structure.
@@ -1735,12 +1858,11 @@ structure:
@c
@c
@c
-
@page
-@subsection fchmod() for Devices
+@subsubsection IMFS_fchmod() for Devices
-@subheading Slot Function:
+@subheading Corresponding Structure Element:
IMFS_fchmod()
@@ -1755,7 +1877,7 @@ mode_t mode
imfs_fchmod.c
-@subheading Development Comments:
+@subheading Description:
This routine will obtain the pointer to the IMFS_jnode_t structure from the
information currently in the file control block.
@@ -1777,12 +1899,11 @@ based on the mode calling parameter.
@c
@c
@c
-
@page
-@subsection ftruncate() for Devices
+@subsubsection No ftruncate() for Devices
-@subheading Slot Function:
+@subheading Corresponding Structure Element:
XXX
@@ -1793,19 +1914,18 @@ XXX
XXX
-@subheading Development Comments:
+@subheading Description:
XXX
@c
@c
@c
-
@page
-@subsection fpathconf() for Devices
+@subsubsection No fpathconf() for Devices
-@subheading Slot Function:
+@subheading Corresponding Structure Element:
fpathconf
@@ -1817,7 +1937,7 @@ Not Implemented
Not Implemented
-@subheading Development Comments:
+@subheading Description:
Not Implemented
@@ -1825,12 +1945,11 @@ Not Implemented
@c
@c
@c
-
@page
-@subsection fsync() for Devices
+@subsubsection No fsync() for Devices
-@subheading Slot Function:
+@subheading Corresponding Structure Element:
XXX
@@ -1842,7 +1961,7 @@ XXX
XXX
-@subheading Development Comments:
+@subheading Description:
XXX
@@ -1850,14 +1969,13 @@ XXX
@c
@c
@c
-
@page
-@subsection fdatasync() for Devices
+@subsubsection No fdatasync() for Devices
Not Implemented
-@subheading Slot Function:
+@subheading Corresponding Structure Element:
XXX
@@ -1869,7 +1987,7 @@ XXX
XXX
-@subheading Development Comments:
+@subheading Description:
XXX
diff --git a/doc/filesystem/init.t b/doc/filesystem/init.t
index d3f6ce0928..cabc3459bd 100644
--- a/doc/filesystem/init.t
+++ b/doc/filesystem/init.t
@@ -11,7 +11,7 @@
After the RTEMS initialization is performed, the application's
initialization will be performed. Part of initialization is a call to
rtems_filesystem_initialize(). This routine will mount the `In Memory File
-System' as the base file system. Mounting the base file system consists
+System' as the base filesystem. Mounting the base filesystem consists
of the following:
@itemize @bullet
@@ -24,19 +24,19 @@ of the `In Memory Filesystem'
@item Initialization of the allocated @code{jnode} with the appropriate OPS,
directory handlers and pathconf limits and options.
-@item Allocation of a memory region for file system specific global
+@item Allocation of a memory region for filesystem specific global
management variables
-@item Creation of first mount table entry for the base file system
+@item Creation of first mount table entry for the base filesystem
@item Initialization of the first mount table chain entry to indicate that
-the mount point is NULL and the mounted file system is the base file
+the mount point is NULL and the mounted filesystem is the base file
system
@end itemize
-After the base file system has been mounted, the following operations are
+After the base filesystem has been mounted, the following operations are
performed under its directory structure:
@itemize @bullet
@@ -47,3 +47,67 @@ performed under its directory structure:
@end itemize
+@section Base Filesystem
+
+RTEMS initially mounts a RAM based file system known as the base file system.
+The root directory of this file system tree serves as the logical root of the
+directory hierarchy (Figure 3). Under the root directory a `/dev' directory
+is created under which all I/O device directories and files are registered as
+part of the file system hierarchy.
+
+@example
+Figure of the tree structure goes here.
+@end example
+
+A RAM based file system draws its management resources from memory. File and
+directory nodes are simply allocated blocks of memory. Data associated with
+regular files is stored in collections of memory blocks. When the system is
+turned off or restarted all memory-based components of the file system are
+lost.
+
+The base file system serves as a starting point for the mounting of file
+systems that are resident on semi-permanent storage media. Examples of such
+media include non- volatile memory, flash memory and IDE hard disk drives
+(Figure 3). File systems of other types will be mounted onto mount points
+within the base file system or other file systems that are subordinate to the
+base file system. The framework set up under the base file system will allow
+for these new file system types and the unique data and functionality that is
+required to manage the future file systems.
+
+@subsection Base Filesystem Mounting
+
+At present, the first file system to be mounted is the `In Memory File
+System'. It is mounted using a standard MOUNT() command in which the mount
+point is NULL. This flags the mount as the first file system to be
+registered under the operating system and appropriate initialization of file
+system management information is performed (See figures 4 and 5). If a
+different file system type is desired as the base file system, alterations
+must be made to base_fs.c. This routine handles the mount of the base file
+system.
+
+
+@example
+Figure of the mount table chain goes here.
+@end example
+
+
+Once the root of the base file system has been established and it has been
+recorded as the mount point of the base file system, devices are integrated
+into the base file system. For every device that is configured into the
+system (See ioman.c) a device registration process is performed. Device
+registration produces a unique dev_t handle that consists of a major and
+minor device number. In addition, the configuration information for each
+device contains a text string that represents the fully qualified pathname to
+that device's place in the base file system's hierarchy. A file system node
+is created for the device along the specified registration path.
+
+
+@example
+Figure of the Mount Table Processing goes here.
+@end example
+
+
+Note: Other file systems can be mounted but they are mounted onto points
+(directory mount points) in the base file system.
+
+
diff --git a/doc/filesystem/mounting.t b/doc/filesystem/mounting.t
index 00671a70b7..b835b8cbda 100644
--- a/doc/filesystem/mounting.t
+++ b/doc/filesystem/mounting.t
@@ -16,20 +16,26 @@ The following is the list of the characteristics of a mount point:
@item The mount point must be a directory. It may have files and other
directories under it. These files and directories will be hidden when the
-file system is mounted.
+filesystem is mounted.
@item The task must have read/write/execute permissions to the mount point
or the mount attempt will be rejected.
-@item Only one file system can be mounted to a single mount point.
+@item Only one filesystem can be mounted to a single mount point.
-@item The Root of the mountable file system will be referenced by the name
+@item The Root of the mountable filesystem will be referenced by the name
of the mount point after the mount is complete.
@end itemize
@section Mount Table Chain
+The mount table chain is a dynamic list of structures that describe
+mounted filesystems a specific points in the filesystem hierarchy. It is
+initialized to an empty state during the base filesystem initialization.
+The mount operation will add entries to the mount table chain. The
+un-mount operation will remove entries from the mount table chain.
+
Each entry in the mount table chain is of the following type:
@example
@@ -56,15 +62,13 @@ struct rtems_filesystem_mount_table_entry_tt
@section Adding entries to the chain during mount
-When a file system is mounted, its presence and location in the file
+When a filesystem is mounted, its presence and location in the file
system hierarchy is recorded in a dynamic list structure known as a chain.
A unique rtems_filesystem_mount_table_entry_tt structure is logged for
-each file system that is mounted. This includes the base file system.
+each filesystem that is mounted. This includes the base filesystem.
@section Removing entries from the chain during unmount
-When a file system is dismounted its entry in the mount table chain is
+When a filesystem is dismounted its entry in the mount table chain is
extracted and the memory for this entry is freed.
-
-
diff --git a/doc/filesystem/patheval.t b/doc/filesystem/patheval.t
index c4aa6088f5..b5108f08fb 100644
--- a/doc/filesystem/patheval.t
+++ b/doc/filesystem/patheval.t
@@ -20,7 +20,7 @@ permissions, and return information on a node that is to become a parent.
Additionally, evalformake() returns a pointer to the start of the name of
the new node to be created.
-@item Pathname evaluation is specific to a file system
+@item Pathname evaluation is specific to a filesystem
@item Mechanics of crossing a mount point during the evaluation of a path
name
@@ -29,13 +29,13 @@ name
@itemize @bullet
-@item Finding file system node information
+@item Finding filesystem node information
-@item Finding file system node handlers
+@item Finding filesystem node handlers
-@item Finding file system node operations table
+@item Finding filesystem node operations table
-@item Finding mount table entry for the file system that this node is part
+@item Finding mount table entry for the filesystem that this node is part
of
@end itemize
diff --git a/doc/filesystem/preface.texi b/doc/filesystem/preface.texi
index a402500a82..39eafe18b2 100644
--- a/doc/filesystem/preface.texi
+++ b/doc/filesystem/preface.texi
@@ -7,12 +7,13 @@
@c
@ifinfo
-@node Preface, Base Filesystem, Top, Top
+@node Preface, , Top, Top
@end ifinfo
@unnumbered Preface
-The following file system capabilities have been added to the existing
-RTEMS system:
+This document describes the implementation of the RTEMS filesystem
+infrastructure. This infrastructure supports the following
+capabilities:
@itemize @bullet
@@ -40,33 +41,43 @@ RTEMS system:
@end enumerate
-@item Hard links to files and directories are supported
+@item Hard links to files and directories
-@item Symbolic links to files and directories are supported
+@item Symbolic links to files and directories
@end itemize
-These enhancements have been made to provide the framework for `UNIX like'
-file system support. The POSIX file and directory functions have been
-implemented to allow a standard method of accessing file, device and
-directory information within the file system. The file system concept that
+This has been implemented to provide the framework for a UNIX-like
+file system support. POSIX file and directory functions have been
+implemented that allow a standard method of accessing file, device and
+directory information within file systems. The file system concept that
has been implemented allows for expansion and adaptation of the file
system to a variety of existing and future data storage devices. To this
end, file system mount and unmount capabilities have been included in this
RTEMS framework.
This framework slightly alters the manner in which devices are handled
-under RTEMS. Devices that are defined under a given RTEMS configuration
-will now be registered as files in a mounted file system. Access to these
-devices and their associated device handlers will be obtained through the
-traditional file system open(), read(), write(), lseek(), fstat() and
-ioctl() functions.
-
-A node structure is maintained for each file, device, and directory in the
-file system. The node structure is used to manage ownership, access
-rights, access time, modification time, and creation time. A union of
-structures within the nodal structure provide for manipulation of file
-data, device selection, or directory content as required by the nodal
-type. Manipulation of these properties is accomplished through the POSIX
-set of file and directory functions.
-
+under RTEMS from that of public release 4.0.0 and earlier. Devices that
+are defined under a given RTEMS configuration will now be registered as
+files in a mounted file system. Access to these device drivers and their
+associated devices may now be performed through the traditional file system
+open(), read(), write(), lseek(), fstat() and ioctl() functions in addition
+to the interface provided by the IO Manager in the RTEMS Classic API.
+
+An In-Memory File System (IMFS) is included which provides full POSIX
+filesystem functionality yet is RAM based. The IMFS maintains a
+node structure for each file, device, and directory in each mounted
+instantiation of its file system. The node structure is used to
+manage ownership, access rights, access time, modification time,
+and creation time. A union of structures within the IMFS nodal
+structure provide for manipulation of file data, device selection,
+or directory content as required by the nodal type. Manipulation of
+these properties is accomplished through the POSIX set of file and
+directory functions. In addition to being useful in its own right,
+the IMFS serves as a full featured example filesystem.
+
+The intended audience for this document is those persons implementing
+their own filesystem. Users of the filesystem may find information
+on the implementation useful. But the user interface to the filesystem
+is through the ISO/ANSI C Library and POSIX 1003.1b file and directory
+APIs.
diff --git a/doc/filesystem/syscalls.t b/doc/filesystem/syscalls.t
index 7948a8796a..eb3a7c815c 100644
--- a/doc/filesystem/syscalls.t
+++ b/doc/filesystem/syscalls.t
@@ -9,7 +9,7 @@
@chapter System Call Development Notes
This set of routines represents the application's interface to files and directories
-under the RTEMS file system. All routines are compliant with POSIX standards if a
+under the RTEMS filesystem. All routines are compliant with POSIX standards if a
specific interface has been established. The list below represents the routines that have
been included as part of the application's interface.
@@ -63,7 +63,7 @@ function.
This routine is layered on top of the stat() function. As long as the st_mode
element in the returned structure follow the standard UNIX conventions, this
-function should support other file systems without alteration.
+function should support other filesystems without alteration.
@page
@section chdir
@@ -84,10 +84,10 @@ rtems_filesystem_evaluate_path() routine.
@subheading Development Comments:
This routine is layered on the rtems_filesystem_evaluate_path() routine and the
-file system specific OP table function node_type().
+filesystem specific OP table function node_type().
-The routine node_type() must be a routine provided for each file system since it
-must access the file systems node information to determine which of the
+The routine node_type() must be a routine provided for each filesystem since it
+must access the filesystems node information to determine which of the
following types the node is:
@itemize @bullet
@@ -98,7 +98,7 @@ following types the node is:
@end itemize
This acknowledges that the form of the node management information can vary
-from one file system implementation to another.
+from one filesystem implementation to another.
RTEMS has a special global structure that maintains the current directory
location. This global variable is of type rtems_filesystem_location_info_t and is
@@ -118,7 +118,7 @@ chmod.c
This routine is layered on the open(), fchmod () and close () functions. As long as
the standard interpretation of the mode_t value is maintained, this routine should
-not need modification to support other file systems.
+not need modification to support other filesystems.
@subheading Development Comments:
@@ -149,7 +149,7 @@ system.
rtems_filesystem_evaluate_path() is used to determine if the path specified
actually exists. If it does a rtems_filesystem_location_info_t structure will be
obtained that allows the shell function to locate the OPS table that is to be used
-for this file system.
+for this filesystem.
It is possible that the chown() function that should be in the OPS table is not
defined. A test for a non-NULL OPS table chown() entry is performed before the
@@ -174,7 +174,7 @@ appropriate network function handler will be selected from a table of previously
registered network functions (rtems_libio_handlers) and that function will be
invoked.
-If the file descriptor refers to an entry in the file system, the appropriate handler
+If the file descriptor refers to an entry in the filesystem, the appropriate handler
will be selected using information that has been placed in the file control block for
the device (rtems_libio_t structure).
@@ -190,9 +190,9 @@ handler invoked and the status of the network handler will be returned to the
calling process.
If none of the upper bits are set in the file descriptor index, the file descriptor
-refers to an element of the RTEMS file system.
+refers to an element of the RTEMS filesystem.
-The following sequence will be performed for any file system file descriptor:
+The following sequence will be performed for any filesystem file descriptor:
@enumerate
@@ -202,7 +202,7 @@ file descriptor
@item Range check the file descriptor using rtems_libio_check_fd()
@item Determine if there is actually a function in the selected handler table that
-processes the close() operation for the file system and node type selected.
+processes the close() operation for the filesystem and node type selected.
This is generally done to avoid execution attempts on functions that have not
been implemented.
@@ -229,7 +229,7 @@ closedir.c
The code was obtained from the BSD group. This routine must clean up the
memory resources that are required to track an open directory. The code is layered
on the close() function and standard memory free () functions. It should not
-require alterations to support other file systems.
+require alterations to support other filesystems.
@subheading Development Comments:
@@ -287,7 +287,7 @@ fchmod.c
@subheading Processing:
-This routine will alter the permissions of a node in a file system. It is layered on
+This routine will alter the permissions of a node in a filesystem. It is layered on
the following functions and macros:
@itemize @bullet
@@ -333,7 +333,7 @@ fcntl.c
This routine currently only interacts with the file control block. If the structure of
the file control block and the associated meanings do not change, the partial
-implementation of fcntl() should remain unaltered for other file system
+implementation of fcntl() should remain unaltered for other filesystem
implementations.
@subheading Development Comments:
@@ -368,9 +368,9 @@ fdatasync.c
@subheading Processing:
-This routine is a template in the in memory file system that will route us to the
+This routine is a template in the in memory filesystem that will route us to the
appropriate handler function to carry out the fdatasync() processing. In the in
-memory file system this function is not necessary. Its function in a disk based file
+memory filesystem this function is not necessary. Its function in a disk based file
system that employs a memory cache is to flush all memory based data buffers to
disk. It is layered on the following functions and macros:
@@ -430,8 +430,8 @@ This routine is layered on the following functions and macros:
@end itemize
-When a file system is mounted, a set of constants is specified for the file system.
-These constants are stored with the mount table entry for the file system. These
+When a filesystem is mounted, a set of constants is specified for the filesystem.
+These constants are stored with the mount table entry for the filesystem. These
constants appear in the POSIX standard and are listed below.
@itemize @bullet
@@ -465,7 +465,7 @@ constants appear in the POSIX standard and are listed below.
This routine will find the mount table information associated the file control block
for the specified file descriptor parameter. The mount table entry structure
-contains a set of file system specific constants that can be accessed by individual
+contains a set of filesystem specific constants that can be accessed by individual
identifiers.
@subheading Development Comments:
@@ -481,10 +481,10 @@ The file control block is examined to determine if it has read permissions to th
file.
Pathinfo in the file control block is used to locate the mount table entry for the
-file system associated with the file descriptor.
+filesystem associated with the file descriptor.
The mount table entry contains the pathconf_limits_and_options element. This
-element is a table of constants that is associated with the file system.
+element is a table of constants that is associated with the filesystem.
The name argument is used to reference the desired constant from the
pathconf_limits_and_options table.
@@ -505,7 +505,7 @@ implementation of fstat() will return a mode set to S_IFSOCK. In a later version
this routine will map the status of a network connection to an external handler
routine.
-If the file descriptor is associated with a node under a file system, the fstat()
+If the file descriptor is associated with a node under a filesystem, the fstat()
routine will map to the fstat() function taken from the node handler table.
@subheading Development Comments:
@@ -521,7 +521,7 @@ performed. In the current implementation, the file descriptor type processing
needs to be improved. It currently just drops into the normal processing for file
system nodes.
-If the file descriptor is associated with a node under a file system, the following
+If the file descriptor is associated with a node under a filesystem, the following
steps are performed:
@enumerate
@@ -548,8 +548,8 @@ ioctl.c
Not defined in the POSIX 1003.1b standard but commonly supported in most
UNIX and POSIX system. Ioctl() is a catchall for I/O operations. Routine is
-layered on external network handlers and file system specific handlers. The
-development of new file systems should not alter the basic processing performed
+layered on external network handlers and filesystem specific handlers. The
+development of new filesystems should not alter the basic processing performed
by this routine.
@subheading Development Comments:
@@ -559,7 +559,7 @@ The file descriptor is examined to determine if it is associated with a network
device. If it is processing is mapped to an external network handler. The value
returned by this handler is then returned to the calling program.
-File descriptors that are associated with a file system undergo the following
+File descriptors that are associated with a filesystem undergo the following
processing:
@enumerate
@@ -590,7 +590,7 @@ link.c
@subheading Processing:
This routine will establish a hard link to a file, directory or a device. The target of
-the hard link must be in the same file system as the new link being created. A link
+the hard link must be in the same filesystem as the new link being created. A link
to an existing link is also permitted but the existing link is evaluated before the
new link is made. This implies that links to links are reduced to links to files,
directories or devices before they are made.
@@ -607,22 +607,22 @@ rtems_filesystem_evaluate_path()
Rtems_filesystem_get_start_loc() is used to determine where to start the path
evaluation of the new name. This macro examines the first characters of the name
to see if the name of the new link starts with a rtems_filesystem_is_separator. If it
-does the search starts from the root of the RTEMS file system; otherwise the
+does the search starts from the root of the RTEMS filesystem; otherwise the
search will start from the current directory.
-The OPS table evalformake() function for the parent's file system is used to
+The OPS table evalformake() function for the parent's filesystem is used to
locate the node that will be the parent of the new link. It will also locate the start
of the new path's name. This name will be used to define a child under the parent
directory.
If the parent is found, the routine will determine if the hard link that we are trying
-to create will cross a file system boundary. This is not permitted for hard-links.
+to create will cross a filesystem boundary. This is not permitted for hard-links.
-If the hard-link does not cross a file system boundary, a check is performed to
+If the hard-link does not cross a filesystem boundary, a check is performed to
determine if the OPS table contains an entry for the link() function.
If a link() function is defined, the OPS table link () function will be called to
-establish the actual link within the file system.
+establish the actual link within the filesystem.
The return code from the OPS table link() function is returned to the calling
program.
@@ -636,8 +636,8 @@ lseek.c
@subheading Processing:
-This routine is layered on both external handlers and file system / node type
-specific handlers. This routine should allow for the support of new file systems
+This routine is layered on both external handlers and filesystem / node type
+specific handlers. This routine should allow for the support of new filesystems
without modification.
@subheading Development Comments:
@@ -648,7 +648,7 @@ called with the file descriptor, offset and whence as its calling parameters. Th
return code from the external handler will be returned to the calling routine.
If the file descriptor is not associated with a network connection, it is associated
-with a node in a file system. The following steps will be performed for file system nodes:
+with a node in a filesystem. The following steps will be performed for filesystem nodes:
@enumerate
@@ -681,7 +681,7 @@ mkdir.c
@subheading Processing:
-This routine attempts to create a directory node under the file system. The routine
+This routine attempts to create a directory node under the filesystem. The routine
is layered the mknod() function.
@subheading Development Comments:
@@ -697,7 +697,7 @@ mkfifo.c
@subheading Processing:
-This routine attempts to create a FIFO node under the file system. The routine is
+This routine attempts to create a FIFO node under the filesystem. The routine is
layered the mknod() function.
@subheading Development Comments:
@@ -714,7 +714,7 @@ mknod.c
@subheading Processing:
This function will allow for the creation of the following types of nodes under the
-file system:
+filesystem:
@itemize @bullet
@@ -731,11 +731,11 @@ file system:
@end itemize
At the present time, an attempt to create a FIFO will result in an ENOTSUP error
-to the calling function. This routine is layered the file system specific routines
-evalformake and mknod. The introduction of a new file system must include its
+to the calling function. This routine is layered the filesystem specific routines
+evalformake and mknod. The introduction of a new filesystem must include its
own evalformake and mknod function to support the generic mknod() function.
Under this condition the generic mknod() function should accommodate other
-file system types without alteration.
+filesystem types without alteration.
@subheading Development Comments:
@@ -767,10 +767,10 @@ function.
Determine if the pathname leads to a valid directory that can be accessed for the
creation of a node.
-If the pathname is a valid location to create a node, verify that a file system
+If the pathname is a valid location to create a node, verify that a filesystem
specific mknod() function exists.
-If the mknod() function exists, call the file system specific mknod () function.
+If the mknod() function exists, call the filesystem specific mknod () function.
Pass the name, mode, device type and the location information associated with the
directory under which the node will be created.
@@ -796,8 +796,8 @@ This is a pointer to a table of functions that are associated with the file
system that we are about to mount. This is the mechanism to selected file
system type without keeping a dynamic database of all possible file
system types that are valid for the mount operation. Using this method, it
-is only necessary to configure the file systems that we wish to use into the
-RTEMS build. Unused file systems types will not be drawn into the build.
+is only necessary to configure the filesystems that we wish to use into the
+RTEMS build. Unused filesystems types will not be drawn into the build.
char *fsoptions,
@@ -807,24 +807,24 @@ or read/write access. Valid states are "RO" and "RW"
char *device,
This argument is reserved for the name of a device that will be used to
-access the file system information. Current file system implementations
-are memory based and do not require a device to access file system
+access the filesystem information. Current filesystem implementations
+are memory based and do not require a device to access filesystem
information.
char *mount_point
-This is a pathname to a directory in a currently mounted file system that
+This is a pathname to a directory in a currently mounted filesystem that
allows read, write and execute permissions.
@subheading Processing:
-This routine will handle the mounting of a file system on a mount point. If the
+This routine will handle the mounting of a filesystem on a mount point. If the
operation is successful, a pointer to the mount table chain entry associated with
-the mounted file system will be returned to the calling function. The specifics
-about the processing required at the mount point and within the file system being
-mounted is isolated in the file system specific mount() and fsmount_me ()
+the mounted filesystem will be returned to the calling function. The specifics
+about the processing required at the mount point and within the filesystem being
+mounted is isolated in the filesystem specific mount() and fsmount_me ()
functions. This allows the generic mount() function to remain unaltered even if
-new file system types are introduced.
+new filesystem types are introduced.
@@ -833,31 +833,31 @@ new file system types are introduced.
This routine will use get_file_system_options() to determine if the mount options
are valid ("RO" or "RW").
-It confirms that a file system ops-table has been selected.
+It confirms that a filesystem ops-table has been selected.
Space is allocated for a mount table entry and selective elements of the temporary
mount table entry are initialized.
If a mount point is specified:
The mount point is examined to determine that it is a directory and also
-has the appropriate permissions to allow a file system to be mounted.
+has the appropriate permissions to allow a filesystem to be mounted.
The current mount table chain is searched to determine that there is not
-another file system mounted at the mount point we are trying to mount
+another filesystem mounted at the mount point we are trying to mount
onto.
-If a mount function is defined in the ops table for the file system
+If a mount function is defined in the ops table for the filesystem
containing the mount point, it is called at this time.
If no mount point is specified:
Processing if performed to set up the mount table chain entry as the base
-file system.
+filesystem.
-If the fsmount_me() function is specified for ops-table of the file system being
-mounted, that function is called to initialize for the new file system.
+If the fsmount_me() function is specified for ops-table of the filesystem being
+mounted, that function is called to initialize for the new filesystem.
On successful completion, the temporary mount table entry will be placed on the
-mount table chain to record the presence of the mounted file system.
+mount table chain to record the presence of the mounted filesystem.
@page
@section open
@@ -868,9 +868,9 @@ open.c
@subheading Processing:
-This routine is layered on both RTEMS calls and file system specific
+This routine is layered on both RTEMS calls and filesystem specific
implementations of the open() function. These functional interfaces should not
-change for new file systems and therefore this code should be stable as new file
+change for new filesystems and therefore this code should be stable as new file
systems are introduced.
@subheading Development Comments:
@@ -880,12 +880,12 @@ about to open.
It will then test to see if the pathname exists. If it does a
rtems_filesystem_location_info_t data structure will be filled out. This structure
-contains information that associates node information, file system specific
+contains information that associates node information, filesystem specific
functions and mount table chain information with the pathname.
If the create option has been it will attempt to create a node for a regular file along
the specified path. If a file already exists along this path, an error will be
-generated; otherwise, a node will be allocated for the file under the file system
+generated; otherwise, a node will be allocated for the file under the filesystem
that contains the pathname. When a new node is created, it is also evaluated so
that an appropriate rtems_filesystem_location_info_t data structure can be filled
out for the newly created node.
@@ -893,9 +893,9 @@ out for the newly created node.
If the file exists or the new file was created successfully, the file control block
structure will be initialized with handler table information, node information and
the rtems_filesystem_location_info_t data structure that describes the node and
-file system data in detail.
+filesystem data in detail.
-If an open() function exists in the file system specific handlers table for the node
+If an open() function exists in the filesystem specific handlers table for the node
that we are trying to open, it will be called at this time.
If any error is detected in the process, cleanup is performed. It consists of freeing
@@ -916,7 +916,7 @@ opendir.c
This routine will attempt to open a directory for read access. It will setup a DIR
control structure that will be used to access directory information. This routine is
-layered on the generic open() routine and file system specific directory
+layered on the generic open() routine and filesystem specific directory
processing routines.
@subheading Development Comments:
@@ -934,7 +934,7 @@ pathconf.c
This routine will obtain the value of one of the path configuration parameters and
return it to the calling routine. It is layered on the generic open() and fpathconf ()
-functions. These interfaces should not change with the addition of new file system
+functions. These interfaces should not change with the addition of new filesystem
types.
@subheading Development Comments:
@@ -955,9 +955,9 @@ deviceio.c
@subheading Processing:
-This routine is layered on a set of RTEMS calls and file system specific read
+This routine is layered on a set of RTEMS calls and filesystem specific read
operations. The functions are layered in such a way as to isolate them from
-change as new file systems are introduced.
+change as new filesystems are introduced.
@subheading Development Comments:
@@ -967,7 +967,7 @@ If the file descriptor is associated with a network device, the read function wi
mapped to a special network handler. The return code from the network handler
will then be sent as the return code from generic read() function.
-For file descriptors that are associated with the file system the following sequence
+For file descriptors that are associated with the filesystem the following sequence
will be performed:
@enumerate
@@ -1007,7 +1007,7 @@ original form.
@subheading Development Comments:
The routine calls a customized getdents() function that is provided by the user.
-This routine provides the file system specific aspects of reading a directory.
+This routine provides the filesystem specific aspects of reading a directory.
It is layered on the read() function in the directory handler table. This function
has been mapped to the Imfs_dir_read() function.
@@ -1021,22 +1021,22 @@ unmount.c
@subheading Processing:
-This routine will attempt to dismount a mounted file system and then free all
-resources that were allocated for the management of that file system.
+This routine will attempt to dismount a mounted filesystem and then free all
+resources that were allocated for the management of that filesystem.
@subheading Development Comments:
@itemize @bullet
-@item This routine will determine if there are any file systems currently mounted
-under the file system that we are trying to dismount. This would prevent the
-dismount of the file system.
+@item This routine will determine if there are any filesystems currently mounted
+under the filesystem that we are trying to dismount. This would prevent the
+dismount of the filesystem.
-@item It will test to see if the current directory is in the file system that we are
-attempting to dismount. This would prevent the dismount of the file system.
+@item It will test to see if the current directory is in the filesystem that we are
+attempting to dismount. This would prevent the dismount of the filesystem.
@item It will scan all the currently open file descriptors to determine is there is an
-open file descriptor to a file in the file system that we are attempting to
+open file descriptor to a file in the filesystem that we are attempting to
unmount().
@end itemize
@@ -1045,16 +1045,16 @@ If the above preconditions are met then the following sequence is performed:
@enumerate
-@item Call the file system specific unmount() function for the file system that
+@item Call the filesystem specific unmount() function for the filesystem that
contains the mount point. This routine should indicate that the mount point
-no longer has a file system mounted below it.
+no longer has a filesystem mounted below it.
-@item Call the file system specific fsunmount_me() function for the mounted
-file system that we are trying to unmount(). This routine should clean up
+@item Call the filesystem specific fsunmount_me() function for the mounted
+filesystem that we are trying to unmount(). This routine should clean up
any resources that are no longer needed for the management of the file
system being un-mounted.
-@item Extract the mount table entry for the file system that was just dismounted
+@item Extract the mount table entry for the filesystem that was just dismounted
from the mount table chain.
@item Free the memory associated with the extracted mount table entry.