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diff --git a/c-user/config/filesystem.rst b/c-user/config/filesystem.rst new file mode 100644 index 0000000..c565f4c --- /dev/null +++ b/c-user/config/filesystem.rst @@ -0,0 +1,1074 @@ +.. SPDX-License-Identifier: CC-BY-SA-4.0 + +.. Copyright (C) 2020, 2021 embedded brains GmbH & Co. KG +.. Copyright (C) 1988, 2023 On-Line Applications Research Corporation (OAR) + +.. This file is part of the RTEMS quality process and was automatically +.. generated. If you find something that needs to be fixed or +.. worded better please post a report or patch to an RTEMS mailing list +.. or raise a bug report: +.. +.. https://www.rtems.org/bugs.html +.. +.. For information on updating and regenerating please refer to the How-To +.. section in the Software Requirements Engineering chapter of the +.. RTEMS Software Engineering manual. The manual is provided as a part of +.. a release. For development sources please refer to the online +.. documentation at: +.. +.. https://docs.rtems.org + +.. Generated from spec:/acfg/if/group-filesystem + +Filesystem Configuration +======================== + +This section describes configuration options related to filesytems. +By default, the In-Memory Filesystem (IMFS) is used as the base filesystem (also +known as root filesystem). In order to save some memory for your application, +you can disable the filesystem support with the +:ref:`CONFIGURE_APPLICATION_DISABLE_FILESYSTEM` configuration option. +Alternatively, you can strip down the features of the base filesystem with the +:ref:`CONFIGURE_USE_MINIIMFS_AS_BASE_FILESYSTEM` and +:ref:`CONFIGURE_USE_DEVFS_AS_BASE_FILESYSTEM` configuration options. These +three configuration options are mutually exclusive. They are intended for an +advanced application configuration. + +Features of the IMFS can be disabled and enabled with the following +configuration options: + +* :ref:`CONFIGURE_IMFS_DISABLE_CHMOD` + +* :ref:`CONFIGURE_IMFS_DISABLE_CHOWN` + +* :ref:`CONFIGURE_IMFS_DISABLE_LINK` + +* :ref:`CONFIGURE_IMFS_DISABLE_MKNOD` + +* :ref:`CONFIGURE_IMFS_DISABLE_MKNOD_FILE` + +* :ref:`CONFIGURE_IMFS_DISABLE_MOUNT` + +* :ref:`CONFIGURE_IMFS_DISABLE_READDIR` + +* :ref:`CONFIGURE_IMFS_DISABLE_READLINK` + +* :ref:`CONFIGURE_IMFS_DISABLE_RENAME` + +* :ref:`CONFIGURE_IMFS_DISABLE_RMNOD` + +* :ref:`CONFIGURE_IMFS_DISABLE_SYMLINK` + +* :ref:`CONFIGURE_IMFS_DISABLE_UNMOUNT` + +* :ref:`CONFIGURE_IMFS_DISABLE_UTIME` + +* :ref:`CONFIGURE_IMFS_ENABLE_MKFIFO` + +.. Generated from spec:/acfg/if/appl-disable-filesystem + +.. raw:: latex + + \clearpage + +.. index:: CONFIGURE_APPLICATION_DISABLE_FILESYSTEM + +.. _CONFIGURE_APPLICATION_DISABLE_FILESYSTEM: + +CONFIGURE_APPLICATION_DISABLE_FILESYSTEM +---------------------------------------- + +.. rubric:: CONSTANT: + +``CONFIGURE_APPLICATION_DISABLE_FILESYSTEM`` + +.. rubric:: OPTION TYPE: + +This configuration option is a boolean feature define. + +.. rubric:: DEFAULT CONFIGURATION: + +If this configuration option is undefined, then a base filesystem and the +configured filesystems are initialized during system initialization. + +.. rubric:: DESCRIPTION: + +In case this configuration option is defined, then **no base filesystem** is +initialized during system initialization and **no filesystems** are +configured. + +.. rubric:: NOTES: + +Filesystems shall be initialized to support file descriptor based device +drivers and basic input/output functions such as :c:func:`printf`. +Filesystems can be disabled to reduce the memory footprint of an application. + +.. Generated from spec:/acfg/if/filesystem-all + +.. raw:: latex + + \clearpage + +.. index:: CONFIGURE_FILESYSTEM_ALL + +.. _CONFIGURE_FILESYSTEM_ALL: + +CONFIGURE_FILESYSTEM_ALL +------------------------ + +.. rubric:: CONSTANT: + +``CONFIGURE_FILESYSTEM_ALL`` + +.. rubric:: OPTION TYPE: + +This configuration option is a boolean feature define. + +.. rubric:: DEFAULT CONFIGURATION: + +If this configuration option is undefined, then the described feature is not +enabled. + +.. rubric:: DESCRIPTION: + +In case this configuration option is defined, then the following +configuration options will be defined as well + +* :ref:`CONFIGURE_FILESYSTEM_DOSFS`, + +* :ref:`CONFIGURE_FILESYSTEM_FTPFS`, + +* :ref:`CONFIGURE_FILESYSTEM_IMFS`, + +* :ref:`CONFIGURE_FILESYSTEM_JFFS2`, + +* :ref:`CONFIGURE_FILESYSTEM_NFS`, + +* :ref:`CONFIGURE_FILESYSTEM_RFS`, and + +* :ref:`CONFIGURE_FILESYSTEM_TFTPFS`. + +.. Generated from spec:/acfg/if/filesystem-dosfs + +.. raw:: latex + + \clearpage + +.. index:: CONFIGURE_FILESYSTEM_DOSFS + +.. _CONFIGURE_FILESYSTEM_DOSFS: + +CONFIGURE_FILESYSTEM_DOSFS +-------------------------- + +.. rubric:: CONSTANT: + +``CONFIGURE_FILESYSTEM_DOSFS`` + +.. rubric:: OPTION TYPE: + +This configuration option is a boolean feature define. + +.. rubric:: DEFAULT CONFIGURATION: + +If this configuration option is undefined, then the described feature is not +enabled. + +.. rubric:: DESCRIPTION: + +In case this configuration option is defined, then the DOS (FAT) filesystem +is registered, so that instances of this filesystem can be mounted by the +application. + +.. rubric:: NOTES: + +This filesystem requires a Block Device Cache configuration, see +:ref:`CONFIGURE_APPLICATION_NEEDS_LIBBLOCK`. + +.. Generated from spec:/acfg/if/filesystem-ftpfs + +.. raw:: latex + + \clearpage + +.. index:: CONFIGURE_FILESYSTEM_FTPFS + +.. _CONFIGURE_FILESYSTEM_FTPFS: + +CONFIGURE_FILESYSTEM_FTPFS +-------------------------- + +.. rubric:: CONSTANT: + +``CONFIGURE_FILESYSTEM_FTPFS`` + +.. rubric:: OPTION TYPE: + +This configuration option is a boolean feature define. + +.. rubric:: DEFAULT CONFIGURATION: + +If this configuration option is undefined, then the described feature is not +enabled. + +.. rubric:: DESCRIPTION: + +In case this configuration option is defined, then the FTP filesystem (FTP +client) is registered, so that instances of this filesystem +can be mounted by the application. + +.. Generated from spec:/acfg/if/filesystem-imfs + +.. raw:: latex + + \clearpage + +.. index:: CONFIGURE_FILESYSTEM_IMFS + +.. _CONFIGURE_FILESYSTEM_IMFS: + +CONFIGURE_FILESYSTEM_IMFS +------------------------- + +.. rubric:: CONSTANT: + +``CONFIGURE_FILESYSTEM_IMFS`` + +.. rubric:: OPTION TYPE: + +This configuration option is a boolean feature define. + +.. rubric:: DEFAULT CONFIGURATION: + +If this configuration option is undefined, then the described feature is not +enabled. + +.. rubric:: DESCRIPTION: + +In case this configuration option is defined, then the In-Memory Filesystem +(IMFS) is registered, so that instances of this filesystem can be mounted by +the application. + +.. rubric:: NOTES: + +Applications will rarely need this configuration option. This configuration +option is intended for test programs. You do not need to define this +configuration option for the base filesystem (also known as root filesystem). + +.. Generated from spec:/acfg/if/filesystem-jffs2 + +.. raw:: latex + + \clearpage + +.. index:: CONFIGURE_FILESYSTEM_JFFS2 + +.. _CONFIGURE_FILESYSTEM_JFFS2: + +CONFIGURE_FILESYSTEM_JFFS2 +-------------------------- + +.. rubric:: CONSTANT: + +``CONFIGURE_FILESYSTEM_JFFS2`` + +.. rubric:: OPTION TYPE: + +This configuration option is a boolean feature define. + +.. rubric:: DEFAULT CONFIGURATION: + +If this configuration option is undefined, then the described feature is not +enabled. + +.. rubric:: DESCRIPTION: + +In case this configuration option is defined, then the JFFS2 filesystem +is registered, so that instances of this filesystem can be mounted by the +application. + +.. Generated from spec:/acfg/if/filesystem-nfs + +.. raw:: latex + + \clearpage + +.. index:: CONFIGURE_FILESYSTEM_NFS + +.. _CONFIGURE_FILESYSTEM_NFS: + +CONFIGURE_FILESYSTEM_NFS +------------------------ + +.. rubric:: CONSTANT: + +``CONFIGURE_FILESYSTEM_NFS`` + +.. rubric:: OPTION TYPE: + +This configuration option is a boolean feature define. + +.. rubric:: DEFAULT CONFIGURATION: + +If this configuration option is undefined, then the described feature is not +enabled. + +.. rubric:: DESCRIPTION: + +In case this configuration option is defined, then the Network Filesystem +(NFS) client is registered, so that instances of this filesystem can be +mounted by the application. + +.. Generated from spec:/acfg/if/filesystem-rfs + +.. raw:: latex + + \clearpage + +.. index:: CONFIGURE_FILESYSTEM_RFS + +.. _CONFIGURE_FILESYSTEM_RFS: + +CONFIGURE_FILESYSTEM_RFS +------------------------ + +.. rubric:: CONSTANT: + +``CONFIGURE_FILESYSTEM_RFS`` + +.. rubric:: OPTION TYPE: + +This configuration option is a boolean feature define. + +.. rubric:: DEFAULT CONFIGURATION: + +If this configuration option is undefined, then the described feature is not +enabled. + +.. rubric:: DESCRIPTION: + +In case this configuration option is defined, then the RTEMS Filesystem (RFS) +is registered, so that instances of this filesystem can be mounted by the +application. + +.. rubric:: NOTES: + +This filesystem requires a Block Device Cache configuration, see +:ref:`CONFIGURE_APPLICATION_NEEDS_LIBBLOCK`. + +.. Generated from spec:/acfg/if/filesystem-tftpfs + +.. raw:: latex + + \clearpage + +.. index:: CONFIGURE_FILESYSTEM_TFTPFS + +.. _CONFIGURE_FILESYSTEM_TFTPFS: + +CONFIGURE_FILESYSTEM_TFTPFS +--------------------------- + +.. rubric:: CONSTANT: + +``CONFIGURE_FILESYSTEM_TFTPFS`` + +.. rubric:: OPTION TYPE: + +This configuration option is a boolean feature define. + +.. rubric:: DEFAULT CONFIGURATION: + +If this configuration option is undefined, then the described feature is not +enabled. + +.. rubric:: DESCRIPTION: + +In case this configuration option is defined, then the TFTP filesystem (TFTP +client) is registered, so that instances of this filesystem can be mounted by +the application. + +.. Generated from spec:/acfg/if/imfs-disable-chmod + +.. raw:: latex + + \clearpage + +.. index:: CONFIGURE_IMFS_DISABLE_CHMOD + +.. _CONFIGURE_IMFS_DISABLE_CHMOD: + +CONFIGURE_IMFS_DISABLE_CHMOD +---------------------------- + +.. rubric:: CONSTANT: + +``CONFIGURE_IMFS_DISABLE_CHMOD`` + +.. rubric:: OPTION TYPE: + +This configuration option is a boolean feature define. + +.. rubric:: DEFAULT CONFIGURATION: + +If this configuration option is undefined, then the root IMFS supports +changing the mode of files. + +.. rubric:: DESCRIPTION: + +In case this configuration option is defined, then the root IMFS does not +support changing the mode of files (no support for :c:func:`chmod`). + +.. Generated from spec:/acfg/if/imfs-disable-chown + +.. raw:: latex + + \clearpage + +.. index:: CONFIGURE_IMFS_DISABLE_CHOWN + +.. _CONFIGURE_IMFS_DISABLE_CHOWN: + +CONFIGURE_IMFS_DISABLE_CHOWN +---------------------------- + +.. rubric:: CONSTANT: + +``CONFIGURE_IMFS_DISABLE_CHOWN`` + +.. rubric:: OPTION TYPE: + +This configuration option is a boolean feature define. + +.. rubric:: DEFAULT CONFIGURATION: + +If this configuration option is undefined, then the root IMFS supports +changing the ownership of files. + +.. rubric:: DESCRIPTION: + +In case this configuration option is defined, then the root IMFS does not +support changing the ownership of files (no support for :c:func:`chown`). + +.. Generated from spec:/acfg/if/imfs-disable-link + +.. raw:: latex + + \clearpage + +.. index:: CONFIGURE_IMFS_DISABLE_LINK + +.. _CONFIGURE_IMFS_DISABLE_LINK: + +CONFIGURE_IMFS_DISABLE_LINK +--------------------------- + +.. rubric:: CONSTANT: + +``CONFIGURE_IMFS_DISABLE_LINK`` + +.. rubric:: OPTION TYPE: + +This configuration option is a boolean feature define. + +.. rubric:: DEFAULT CONFIGURATION: + +If this configuration option is undefined, then the root IMFS supports hard +links. + +.. rubric:: DESCRIPTION: + +In case this configuration option is defined, then the root IMFS does not +support hard links (no support for :c:func:`link`). + +.. Generated from spec:/acfg/if/imfs-disable-mknod + +.. raw:: latex + + \clearpage + +.. index:: CONFIGURE_IMFS_DISABLE_MKNOD + +.. _CONFIGURE_IMFS_DISABLE_MKNOD: + +CONFIGURE_IMFS_DISABLE_MKNOD +---------------------------- + +.. rubric:: CONSTANT: + +``CONFIGURE_IMFS_DISABLE_MKNOD`` + +.. rubric:: OPTION TYPE: + +This configuration option is a boolean feature define. + +.. rubric:: DEFAULT CONFIGURATION: + +If this configuration option is undefined, then the root IMFS supports making +files. + +.. rubric:: DESCRIPTION: + +In case this configuration option is defined, then the root IMFS does not +support making files (no support for :c:func:`mknod`). + +.. Generated from spec:/acfg/if/imfs-disable-mknod-device + +.. raw:: latex + + \clearpage + +.. index:: CONFIGURE_IMFS_DISABLE_MKNOD_DEVICE + +.. _CONFIGURE_IMFS_DISABLE_MKNOD_DEVICE: + +CONFIGURE_IMFS_DISABLE_MKNOD_DEVICE +----------------------------------- + +.. rubric:: CONSTANT: + +``CONFIGURE_IMFS_DISABLE_MKNOD_DEVICE`` + +.. rubric:: OPTION TYPE: + +This configuration option is a boolean feature define. + +.. rubric:: DEFAULT CONFIGURATION: + +If this configuration option is undefined, then the root IMFS supports making +device files. + +.. rubric:: DESCRIPTION: + +In case this configuration option is defined, then the root IMFS does not +support making device files. + +.. Generated from spec:/acfg/if/imfs-disable-mknod-file + +.. raw:: latex + + \clearpage + +.. index:: CONFIGURE_IMFS_DISABLE_MKNOD_FILE + +.. _CONFIGURE_IMFS_DISABLE_MKNOD_FILE: + +CONFIGURE_IMFS_DISABLE_MKNOD_FILE +--------------------------------- + +.. rubric:: CONSTANT: + +``CONFIGURE_IMFS_DISABLE_MKNOD_FILE`` + +.. rubric:: OPTION TYPE: + +This configuration option is a boolean feature define. + +.. rubric:: DEFAULT CONFIGURATION: + +If this configuration option is undefined, then the root IMFS supports making +regular files. + +.. rubric:: DESCRIPTION: + +In case this configuration option is defined, then the root IMFS does not +support making regular files. + +.. Generated from spec:/acfg/if/imfs-disable-mount + +.. raw:: latex + + \clearpage + +.. index:: CONFIGURE_IMFS_DISABLE_MOUNT + +.. _CONFIGURE_IMFS_DISABLE_MOUNT: + +CONFIGURE_IMFS_DISABLE_MOUNT +---------------------------- + +.. rubric:: CONSTANT: + +``CONFIGURE_IMFS_DISABLE_MOUNT`` + +.. rubric:: OPTION TYPE: + +This configuration option is a boolean feature define. + +.. rubric:: DEFAULT CONFIGURATION: + +If this configuration option is undefined, then the root IMFS supports +mounting other filesystems. + +.. rubric:: DESCRIPTION: + +In case this configuration option is defined, then the root IMFS does not +support mounting other filesystems (no support for +:c:func:`mount`). + +.. Generated from spec:/acfg/if/imfs-disable-readdir + +.. raw:: latex + + \clearpage + +.. index:: CONFIGURE_IMFS_DISABLE_READDIR + +.. _CONFIGURE_IMFS_DISABLE_READDIR: + +CONFIGURE_IMFS_DISABLE_READDIR +------------------------------ + +.. rubric:: CONSTANT: + +``CONFIGURE_IMFS_DISABLE_READDIR`` + +.. rubric:: OPTION TYPE: + +This configuration option is a boolean feature define. + +.. rubric:: DEFAULT CONFIGURATION: + +If this configuration option is undefined, then the root IMFS supports +reading directories. + +.. rubric:: DESCRIPTION: + +In case this configuration option is defined, then the root IMFS does not +support reading directories (no support for :c:func:`readdir`). It is +still possible to open files in a directory. + +.. Generated from spec:/acfg/if/imfs-disable-readlink + +.. raw:: latex + + \clearpage + +.. index:: CONFIGURE_IMFS_DISABLE_READLINK + +.. _CONFIGURE_IMFS_DISABLE_READLINK: + +CONFIGURE_IMFS_DISABLE_READLINK +------------------------------- + +.. rubric:: CONSTANT: + +``CONFIGURE_IMFS_DISABLE_READLINK`` + +.. rubric:: OPTION TYPE: + +This configuration option is a boolean feature define. + +.. rubric:: DEFAULT CONFIGURATION: + +If this configuration option is undefined, then the root IMFS supports +reading symbolic links. + +.. rubric:: DESCRIPTION: + +In case this configuration option is defined, then the root IMFS does not +support reading symbolic links (no support for :c:func:`readlink`). + +.. Generated from spec:/acfg/if/imfs-disable-rename + +.. raw:: latex + + \clearpage + +.. index:: CONFIGURE_IMFS_DISABLE_RENAME + +.. _CONFIGURE_IMFS_DISABLE_RENAME: + +CONFIGURE_IMFS_DISABLE_RENAME +----------------------------- + +.. rubric:: CONSTANT: + +``CONFIGURE_IMFS_DISABLE_RENAME`` + +.. rubric:: OPTION TYPE: + +This configuration option is a boolean feature define. + +.. rubric:: DEFAULT CONFIGURATION: + +If this configuration option is undefined, then the root IMFS supports +renaming files. + +.. rubric:: DESCRIPTION: + +In case this configuration option is defined, then the root IMFS does not +support renaming files (no support for :c:func:`rename`). + +.. Generated from spec:/acfg/if/imfs-disable-rmnod + +.. raw:: latex + + \clearpage + +.. index:: CONFIGURE_IMFS_DISABLE_RMNOD + +.. _CONFIGURE_IMFS_DISABLE_RMNOD: + +CONFIGURE_IMFS_DISABLE_RMNOD +---------------------------- + +.. rubric:: CONSTANT: + +``CONFIGURE_IMFS_DISABLE_RMNOD`` + +.. rubric:: OPTION TYPE: + +This configuration option is a boolean feature define. + +.. rubric:: DEFAULT CONFIGURATION: + +If this configuration option is undefined, then the root IMFS supports +removing files. + +.. rubric:: DESCRIPTION: + +In case this configuration option is defined, then the root IMFS does not +support removing files (no support for :c:func:`rmnod`). + +.. Generated from spec:/acfg/if/imfs-disable-symlink + +.. raw:: latex + + \clearpage + +.. index:: CONFIGURE_IMFS_DISABLE_SYMLINK + +.. _CONFIGURE_IMFS_DISABLE_SYMLINK: + +CONFIGURE_IMFS_DISABLE_SYMLINK +------------------------------ + +.. rubric:: CONSTANT: + +``CONFIGURE_IMFS_DISABLE_SYMLINK`` + +.. rubric:: OPTION TYPE: + +This configuration option is a boolean feature define. + +.. rubric:: DEFAULT CONFIGURATION: + +If this configuration option is undefined, then the root IMFS supports +creating symbolic links. + +.. rubric:: DESCRIPTION: + +In case this configuration option is defined, then the root IMFS does not +support creating symbolic links (no support for :c:func:`symlink`). + +.. Generated from spec:/acfg/if/imfs-disable-unmount + +.. raw:: latex + + \clearpage + +.. index:: CONFIGURE_IMFS_DISABLE_UNMOUNT + +.. _CONFIGURE_IMFS_DISABLE_UNMOUNT: + +CONFIGURE_IMFS_DISABLE_UNMOUNT +------------------------------ + +.. rubric:: CONSTANT: + +``CONFIGURE_IMFS_DISABLE_UNMOUNT`` + +.. rubric:: OPTION TYPE: + +This configuration option is a boolean feature define. + +.. rubric:: DEFAULT CONFIGURATION: + +If this configuration option is undefined, then the root IMFS supports +unmounting other filesystems. + +.. rubric:: DESCRIPTION: + +In case this configuration option is defined, then the root IMFS does not +support unmounting other filesystems (no support for +:c:func:`unmount`). + +.. Generated from spec:/acfg/if/imfs-disable-utime + +.. raw:: latex + + \clearpage + +.. index:: CONFIGURE_IMFS_DISABLE_UTIME + +.. _CONFIGURE_IMFS_DISABLE_UTIME: + +CONFIGURE_IMFS_DISABLE_UTIME +---------------------------- + +.. rubric:: CONSTANT: + +``CONFIGURE_IMFS_DISABLE_UTIME`` + +.. rubric:: OPTION TYPE: + +This configuration option is a boolean feature define. + +.. rubric:: DEFAULT CONFIGURATION: + +If this configuration option is undefined, then the root IMFS supports +changing file times. + +.. rubric:: DESCRIPTION: + +In case this configuration option is defined, then the root IMFS does not +support changing file times (no support for :c:func:`utime`). + +.. Generated from spec:/acfg/if/imfs-enable-mkfifo + +.. raw:: latex + + \clearpage + +.. index:: CONFIGURE_IMFS_ENABLE_MKFIFO + +.. _CONFIGURE_IMFS_ENABLE_MKFIFO: + +CONFIGURE_IMFS_ENABLE_MKFIFO +---------------------------- + +.. rubric:: CONSTANT: + +``CONFIGURE_IMFS_ENABLE_MKFIFO`` + +.. rubric:: OPTION TYPE: + +This configuration option is a boolean feature define. + +.. rubric:: DEFAULT CONFIGURATION: + +If this configuration option is undefined, then the root IMFS does not +support making FIFOs (no support for :c:func:`mkfifo`). + +.. rubric:: DESCRIPTION: + +In case this configuration option is defined, then the root IMFS supports +making FIFOs. + +.. Generated from spec:/acfg/if/imfs-memfile-bytes-per-block + +.. raw:: latex + + \clearpage + +.. index:: CONFIGURE_IMFS_MEMFILE_BYTES_PER_BLOCK + +.. _CONFIGURE_IMFS_MEMFILE_BYTES_PER_BLOCK: + +CONFIGURE_IMFS_MEMFILE_BYTES_PER_BLOCK +-------------------------------------- + +.. rubric:: CONSTANT: + +``CONFIGURE_IMFS_MEMFILE_BYTES_PER_BLOCK`` + +.. rubric:: OPTION TYPE: + +This configuration option is an integer define. + +.. rubric:: DEFAULT VALUE: + +The default value is 128. + +.. rubric:: DESCRIPTION: + +The value of this configuration option defines the block size for in-memory +files managed by the IMFS. + +.. rubric:: NOTES: + +The configured block size has two impacts. The first is the average amount of +unused memory in the last block of each file. For example, when the block +size is 512, on average one-half of the last block of each file will remain +unused and the memory is wasted. In contrast, when the block size is 16, the +average unused memory per file is only 8 bytes. However, it requires more +allocations for the same size file and thus more overhead per block for the +dynamic memory management. + +Second, the block size has an impact on the maximum size file that can be +stored in the IMFS. With smaller block size, the maximum file size is +correspondingly smaller. The following shows the maximum file size possible +based on the configured block size: + +* when the block size is 16 bytes, the maximum file size is 1,328 bytes. + +* when the block size is 32 bytes, the maximum file size is 18,656 bytes. + +* when the block size is 64 bytes, the maximum file size is 279,488 bytes. + +* when the block size is 128 bytes, the maximum file size is 4,329,344 bytes. + +* when the block size is 256 bytes, the maximum file size is 68,173,568 bytes. + +* when the block size is 512 bytes, the maximum file size is 1,082,195,456 + bytes. + +.. rubric:: CONSTRAINTS: + +The value of the configuration option shall be equal to 16, 32, 64, 128, 256, +or 512. + +.. Generated from spec:/acfg/if/jffs2-delayed-write-task-priority + +.. raw:: latex + + \clearpage + +.. index:: CONFIGURE_JFFS2_DELAYED_WRITE_TASK_PRIORITY + +.. _CONFIGURE_JFFS2_DELAYED_WRITE_TASK_PRIORITY: + +CONFIGURE_JFFS2_DELAYED_WRITE_TASK_PRIORITY +------------------------------------------- + +.. rubric:: CONSTANT: + +``CONFIGURE_JFFS2_DELAYED_WRITE_TASK_PRIORITY`` + +.. rubric:: OPTION TYPE: + +This configuration option is an integer define. + +.. rubric:: DEFAULT VALUE: + +The default value is 15. + +.. rubric:: DESCRIPTION: + +The value of this configuration option defines the JFFS2 delayed write task priority. + +.. rubric:: CONSTRAINTS: + +The value of the configuration option shall be a valid Classic API task +priority. The set of valid task priorities depends on the scheduler +configuration. + +.. Generated from spec:/acfg/if/use-devfs-as-base-filesystem + +.. raw:: latex + + \clearpage + +.. index:: CONFIGURE_USE_DEVFS_AS_BASE_FILESYSTEM + +.. _CONFIGURE_USE_DEVFS_AS_BASE_FILESYSTEM: + +CONFIGURE_USE_DEVFS_AS_BASE_FILESYSTEM +-------------------------------------- + +.. rubric:: CONSTANT: + +``CONFIGURE_USE_DEVFS_AS_BASE_FILESYSTEM`` + +.. rubric:: OPTION TYPE: + +This configuration option is a boolean feature define. + +.. rubric:: DEFAULT CONFIGURATION: + +If this configuration option is undefined, then the described feature is not +enabled. + +.. rubric:: DESCRIPTION: + +In case this configuration option is defined, then an IMFS with a reduced +feature set will be the base filesystem (also known as root filesystem). + +.. rubric:: NOTES: + +In case this configuration option is defined, then the following +configuration options will be defined as well + +* :ref:`CONFIGURE_IMFS_DISABLE_CHMOD`, + +* :ref:`CONFIGURE_IMFS_DISABLE_CHOWN`, + +* :ref:`CONFIGURE_IMFS_DISABLE_LINK`, + +* :ref:`CONFIGURE_IMFS_DISABLE_MKNOD_FILE`, + +* :ref:`CONFIGURE_IMFS_DISABLE_MOUNT`, + +* :ref:`CONFIGURE_IMFS_DISABLE_READDIR`, + +* :ref:`CONFIGURE_IMFS_DISABLE_READLINK`, + +* :ref:`CONFIGURE_IMFS_DISABLE_RENAME`, + +* :ref:`CONFIGURE_IMFS_DISABLE_RMNOD`, + +* :ref:`CONFIGURE_IMFS_DISABLE_SYMLINK`, + +* :ref:`CONFIGURE_IMFS_DISABLE_UTIME`, and + +* :ref:`CONFIGURE_IMFS_DISABLE_UNMOUNT`. + +In addition, a simplified path evaluation is enabled. It allows only a look +up of absolute paths. + +This configuration of the IMFS is basically a device-only filesystem. It is +comparable in functionality to the pseudo-filesystem name space provided +before RTEMS release 4.5.0. + +.. Generated from spec:/acfg/if/use-miniimfs-as-base-filesystem + +.. raw:: latex + + \clearpage + +.. index:: CONFIGURE_USE_MINIIMFS_AS_BASE_FILESYSTEM + +.. _CONFIGURE_USE_MINIIMFS_AS_BASE_FILESYSTEM: + +CONFIGURE_USE_MINIIMFS_AS_BASE_FILESYSTEM +----------------------------------------- + +.. rubric:: CONSTANT: + +``CONFIGURE_USE_MINIIMFS_AS_BASE_FILESYSTEM`` + +.. rubric:: OPTION TYPE: + +This configuration option is a boolean feature define. + +.. rubric:: DEFAULT CONFIGURATION: + +If this configuration option is undefined, then the described feature is not +enabled. + +.. rubric:: DESCRIPTION: + +In case this configuration option is defined, then an IMFS with a reduced +feature set will be the base filesystem (also known as root filesystem). + +.. rubric:: NOTES: + +In case this configuration option is defined, then the following +configuration options will be defined as well + +* :ref:`CONFIGURE_IMFS_DISABLE_CHMOD`, + +* :ref:`CONFIGURE_IMFS_DISABLE_CHOWN`, + +* :ref:`CONFIGURE_IMFS_DISABLE_LINK`, + +* :ref:`CONFIGURE_IMFS_DISABLE_READLINK`, + +* :ref:`CONFIGURE_IMFS_DISABLE_RENAME`, + +* :ref:`CONFIGURE_IMFS_DISABLE_SYMLINK`, + +* :ref:`CONFIGURE_IMFS_DISABLE_UTIME`, and + +* :ref:`CONFIGURE_IMFS_DISABLE_UNMOUNT`. |