Re: [PATCH] fat: ignore .. subdir and always add a link to dirs

From: Thadeu Lima de Souza Cascardo
Date: Thu Feb 22 2024 - 21:02:38 EST


On Fri, Feb 23, 2024 at 10:52:12AM +0900, OGAWA Hirofumi wrote:
> Thadeu Lima de Souza Cascardo <cascardo@xxxxxxxxxx> writes:
>
> > The tools used for creating images for the Lego Mindstrom EV3 are not
> > adding '.' and '..' entry in the 'Projects' directory.
> >
> > Without this fix, the kernel can not fill the inode structure for
> > 'Projects' directory.
> >
> > See https://github.com/microsoft/pxt-ev3/issues/980
> > And https://github.com/microsoft/uf2-linux/issues/6
> >
> > When counting the number of subdirs, ignore .. subdir and add one when
> > setting the initial link count for directories. This way, when .. is
> > present, it is still accounted for, and when neither . or .. are present, a
> > single link is still done, as it should, since this link would be the one
> > from the parent directory.
> >
> > With this fix applied, we can mount an image with such empty directories,
> > access them, create subdirectories and remove them.
>
> This looks like the bug of those tools, isn't it?
>
> Thanks.
> --
> OGAWA Hirofumi <hirofumi@xxxxxxxxxxxxxxxxxx>

Which they refused to fix, arguing that there are already filesystems out there
in the world like that. Also, there is argument that this works on Windows,
though I haven't been able to test this.

https://github.com/microsoft/pxt-ev3/issues/980
https://github.com/microsoft/uf2-linux/issues/6

Thanks.
Cascardo.