docs: filesystems: convert adfs.txt to ReST

- Add a SPDX header;
- Add a document title;
- Adjust section titles;
- Mark literal blocks as such;
- Add it to filesystems/index.rst.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/15ee92f03ec917e5d26bd7b863565dec88c843f6.1581955849.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

diff --git a/Documentation/filesystems/adfs.rst b/Documentation/filesystems/adfs.rst
new file mode 100644 (file)
index 0000000..5b22cae
--- /dev/null
+++ b/Documentation/filesystems/adfs.rst
@@ -0,0 +1,108 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+===============================
+Acorn Disc Filing System - ADFS
+===============================
+
+Filesystems supported by ADFS
+-----------------------------
+
+The ADFS module supports the following Filecore formats which have:
+
+- new maps
+- new directories or big directories
+
+In terms of the named formats, this means we support:
+
+- E and E+, with or without boot block
+- F and F+
+
+We fully support reading files from these filesystems, and writing to
+existing files within their existing allocation.  Essentially, we do
+not support changing any of the filesystem metadata.
+
+This is intended to support loopback mounted Linux native filesystems
+on a RISC OS Filecore filesystem, but will allow the data within files
+to be changed.
+
+If write support (ADFS_FS_RW) is configured, we allow rudimentary
+directory updates, specifically updating the access mode and timestamp.
+
+Mount options for ADFS
+----------------------
+
+  ============  ======================================================
+  uid=nnn      All files in the partition will be owned by
+               user id nnn.  Default 0 (root).
+  gid=nnn      All files in the partition will be in group
+               nnn.  Default 0 (root).
+  ownmask=nnn  The permission mask for ADFS 'owner' permissions
+               will be nnn.  Default 0700.
+  othmask=nnn  The permission mask for ADFS 'other' permissions
+               will be nnn.  Default 0077.
+  ftsuffix=n   When ftsuffix=0, no file type suffix will be applied.
+               When ftsuffix=1, a hexadecimal suffix corresponding to
+               the RISC OS file type will be added.  Default 0.
+  ============  ======================================================
+
+Mapping of ADFS permissions to Linux permissions
+------------------------------------------------
+
+  ADFS permissions consist of the following:
+
+       - Owner read
+       - Owner write
+       - Other read
+       - Other write
+
+  (In older versions, an 'execute' permission did exist, but this
+  does not hold the same meaning as the Linux 'execute' permission
+  and is now obsolete).
+
+  The mapping is performed as follows::
+
+       Owner read                              -> -r--r--r--
+       Owner write                             -> --w--w---w
+       Owner read and filetype UnixExec        -> ---x--x--x
+    These are then masked by ownmask, eg 700   -> -rwx------
+       Possible owner mode permissions         -> -rwx------
+
+       Other read                              -> -r--r--r--
+       Other write                             -> --w--w--w-
+       Other read and filetype UnixExec        -> ---x--x--x
+    These are then masked by othmask, eg 077   -> ----rwxrwx
+       Possible other mode permissions         -> ----rwxrwx
+
+  Hence, with the default masks, if a file is owner read/write, and
+  not a UnixExec filetype, then the permissions will be::
+
+                       -rw-------
+
+  However, if the masks were ownmask=0770,othmask=0007, then this would
+  be modified to::
+
+                       -rw-rw----
+
+  There is no restriction on what you can do with these masks.  You may
+  wish that either read bits give read access to the file for all, but
+  keep the default write protection (ownmask=0755,othmask=0577)::
+
+                       -rw-r--r--
+
+  You can therefore tailor the permission translation to whatever you
+  desire the permissions should be under Linux.
+
+RISC OS file type suffix
+------------------------
+
+  RISC OS file types are stored in bits 19..8 of the file load address.
+
+  To enable non-RISC OS systems to be used to store files without losing
+  file type information, a file naming convention was devised (initially
+  for use with NFS) such that a hexadecimal suffix of the form ,xyz
+  denoted the file type: e.g. BasicFile,ffb is a BASIC (0xffb) file.  This
+  naming convention is now also used by RISC OS emulators such as RPCEmu.
+
+  Mounting an ADFS disc with option ftsuffix=1 will cause appropriate file
+  type suffixes to be appended to file names read from a directory.  If the
+  ftsuffix option is zero or omitted, no file type suffixes will be added.

diff --git a/Documentation/filesystems/adfs.txt b/Documentation/filesystems/adfs.txt
deleted file mode 100644 (file)
index 0baa8e8..0000000
--- a/Documentation/filesystems/adfs.txt
+++ /dev/null
@@ -1,99 +0,0 @@
-Filesystems supported by ADFS
------------------------------
-
-The ADFS module supports the following Filecore formats which have:
-
-- new maps
-- new directories or big directories
-
-In terms of the named formats, this means we support:
-
-- E and E+, with or without boot block
-- F and F+
-
-We fully support reading files from these filesystems, and writing to
-existing files within their existing allocation.  Essentially, we do
-not support changing any of the filesystem metadata.
-
-This is intended to support loopback mounted Linux native filesystems
-on a RISC OS Filecore filesystem, but will allow the data within files
-to be changed.
-
-If write support (ADFS_FS_RW) is configured, we allow rudimentary
-directory updates, specifically updating the access mode and timestamp.
-
-Mount options for ADFS
-----------------------
-
-  uid=nnn      All files in the partition will be owned by
-               user id nnn.  Default 0 (root).
-  gid=nnn      All files in the partition will be in group
-               nnn.  Default 0 (root).
-  ownmask=nnn  The permission mask for ADFS 'owner' permissions
-               will be nnn.  Default 0700.
-  othmask=nnn  The permission mask for ADFS 'other' permissions
-               will be nnn.  Default 0077.
-  ftsuffix=n   When ftsuffix=0, no file type suffix will be applied.
-               When ftsuffix=1, a hexadecimal suffix corresponding to
-               the RISC OS file type will be added.  Default 0.
-
-Mapping of ADFS permissions to Linux permissions
-------------------------------------------------
-
-  ADFS permissions consist of the following:
-
-       Owner read
-       Owner write
-       Other read
-       Other write
-
-  (In older versions, an 'execute' permission did exist, but this
-   does not hold the same meaning as the Linux 'execute' permission
-   and is now obsolete).
-
-  The mapping is performed as follows:
-
-       Owner read                              -> -r--r--r--
-       Owner write                             -> --w--w---w
-       Owner read and filetype UnixExec        -> ---x--x--x
-    These are then masked by ownmask, eg 700   -> -rwx------
-       Possible owner mode permissions         -> -rwx------
-
-       Other read                              -> -r--r--r--
-       Other write                             -> --w--w--w-
-       Other read and filetype UnixExec        -> ---x--x--x
-    These are then masked by othmask, eg 077   -> ----rwxrwx
-       Possible other mode permissions         -> ----rwxrwx
-
-  Hence, with the default masks, if a file is owner read/write, and
-  not a UnixExec filetype, then the permissions will be:
-
-                       -rw-------
-
-  However, if the masks were ownmask=0770,othmask=0007, then this would
-  be modified to:
-                       -rw-rw----
-
-  There is no restriction on what you can do with these masks.  You may
-  wish that either read bits give read access to the file for all, but
-  keep the default write protection (ownmask=0755,othmask=0577):
-
-                       -rw-r--r--
-
-  You can therefore tailor the permission translation to whatever you
-  desire the permissions should be under Linux.
-
-RISC OS file type suffix
-------------------------
-
-  RISC OS file types are stored in bits 19..8 of the file load address.
-
-  To enable non-RISC OS systems to be used to store files without losing
-  file type information, a file naming convention was devised (initially
-  for use with NFS) such that a hexadecimal suffix of the form ,xyz
-  denoted the file type: e.g. BasicFile,ffb is a BASIC (0xffb) file.  This
-  naming convention is now also used by RISC OS emulators such as RPCEmu.
-
-  Mounting an ADFS disc with option ftsuffix=1 will cause appropriate file
-  type suffixes to be appended to file names read from a directory.  If the
-  ftsuffix option is zero or omitted, no file type suffixes will be added.

diff --git a/Documentation/filesystems/index.rst b/Documentation/filesystems/index.rst
index a9330c3f8c2ee7e71ced65f711e3d59f57c6a114..14dc89c948226f4c0f4c7a9c536cb4647461f7df 100644 (file)
--- a/Documentation/filesystems/index.rst
+++ b/Documentation/filesystems/index.rst
@@ -47,6 +47,7 @@ Documentation for filesystem implementations.
    :maxdepth: 2
 
    9p
+   adfs
    autofs
    fuse
    overlayfs