silent semantic changes with reiser4

Christoph Hellwig
2004-08-24T20:25:28Z

After looking trough the code and mailinglists I'm quite unhappy with
a bunch of user-visible changes that Hans sneaked in and make reiser4
incompatible with other filesystems and have a slight potential to break
even in the kernel.

o files as directories
- O_DIRECTORY opens succeed on all files on reiser4. Besides breaking
.htaccess handling in apache and glibc compilation this also renders
this flag entirely useless and opens up the races it tries to
prevent against cmpletely useless
- meaning of the -x permission. This one has different meanings on
directories vs files on UNIX systems. If we want to support
directories as files we'll probably have to find a way to work
around this.
- dentry aliasing. I can't find a formal guarantee in the code this
can't happen

o metafiles - ..metas as a magic name that's just taken out of the
namespace doesn't sound like a good idea. If we want this it should
be a VFS-level option and there should be a translation-layer to
xattrs. Not doing this will again confuse applications greatly that
expect uniform filesystem behaviour.

Given these problems I request that these interfaces are removed from
reiser4 for the kernel merge, and if added later at the proper VFS level
after discussion on linux-kernel and linux-fsdevel, like we did for
xattrs.