fat: Add allow_utime option
Normally utime(2) checks current process is owner of the file, or it
has CAP_FOWNER capability. But FAT filesystem doesn't have uid/gid as
on disk info, so normal check is too unflexible.
With this option you can relax it.
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/Documentation/filesystems/vfat.txt b/Documentation/filesystems/vfat.txt
index fcc123f..2d5e1e5 100644
--- a/Documentation/filesystems/vfat.txt
+++ b/Documentation/filesystems/vfat.txt
@@ -17,6 +17,21 @@
fmask=### -- The permission mask for files.
The default is the umask of current process.
+allow_utime=### -- This option controls the permission check of mtime/atime.
+
+ 20 - If current process is in group of file's group ID,
+ you can change timestamp.
+ 2 - Other users can change timestamp.
+
+ The default is set from `dmask' option. (If the directory is
+ writable, utime(2) is also allowed. I.e. ~dmask & 022)
+
+ Normally utime(2) checks current process is owner of
+ the file, or it has CAP_FOWNER capability. But FAT
+ filesystem doesn't have uid/gid on disk, so normal
+ check is too unflexible. With this option you can
+ relax it.
+
codepage=### -- Sets the codepage number for converting to shortname
characters on FAT filesystem.
By default, FAT_DEFAULT_CODEPAGE setting is used.