Document mounting options for casefold support in tmpfs.
Signed-off-by: André Almeida <andrealmeid@xxxxxxxxxx>
---
Documentation/filesystems/tmpfs.rst | 37 +++++++++++++++++++++++++++++
1 file changed, 37 insertions(+)
diff --git a/Documentation/filesystems/tmpfs.rst b/Documentation/filesystems/tmpfs.rst
index 56a26c843dbe..ce24fb16979a 100644
--- a/Documentation/filesystems/tmpfs.rst
+++ b/Documentation/filesystems/tmpfs.rst
@@ -241,6 +241,41 @@ So 'mount -t tmpfs -o size=10G,nr_inodes=10k,mode=700 tmpfs /mytmpfs'
will give you tmpfs instance on /mytmpfs which can allocate 10GB
RAM/SWAP in 10240 inodes and it is only accessible by root.
+tmpfs has the following mounting options for case-insesitive lookups support:
+
+================= ==============================================================
+casefold Enable casefold support at this mount point using the given
+ argument as the encoding standard. Currently only utf8
+ encodings are supported.
+strict_encoding Enable strict encoding at this mount point (disabled by
+ default). This means that invalid sequences will be rejected
+ by the file system.
+================= ==============================================================
+
+Note that this option doesn't enable casefold by default; one needs to set
+casefold flag per directory, setting the +F attribute in an empty directory. New
+directories within a casefolded one will inherit the flag.
+
+Example::
+
+ $ mount -t tmpfs -o casefold=utf8-12.1.0,cf_strict fs_name /mytmpfs
+ $ cd /mytmpfs # case-sensitive by default
+ $ touch a; touch A
+ $ ls
+ A a
+ $ mkdir B
+ $ cd b
+ cd: The directory 'b' does not exist
+ $ mkdir casefold_dir
+ $ chattr +F casefold_dir/ # marking it as case-insensitive
+ $ cd
+ $ touch dir/a; touch dir/A
+ $ ls dir
+ a
+ $ mkdir B
+ $ cd b
+ $ pwd
+ /home/user/mytmpfs/casefold_dir/B
:Author:
Christoph Rohland <cr@xxxxxxx>, 1.12.01
@@ -250,3 +285,5 @@ RAM/SWAP in 10240 inodes and it is only accessible by root.
KOSAKI Motohiro, 16 Mar 2010
:Updated:
Chris Down, 13 July 2020
+:Updated:
+ André Almeida, 23 Aug 2024
--
2.46.0
