From mboxrd@z Thu Jan 1 00:00:00 1970 From: Spam Subject: Re: silent semantic changes with reiser4 Date: Tue, 7 Sep 2004 23:29:35 +0200 Message-ID: <2010165891.20040907232935@tnonline.net> References: Message from Hans Reiser of "Tue, 07 Sep 2004 12:14:44 MST." <413E08A4.9020005@namesys.com> <200409072102.i87L2K4u005503@laptop11.inf.utfsm.cl> Reply-To: Spam Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: Hans Reiser , Christer Weinigel , David Masover , Tonnerre , Linus Torvalds , Pavel Machek , Jamie Lokier , Chris Wedgwood , , Christoph Hellwig , , , Alexander Lyamin aka FLX , ReiserFS List Return-path: list-help: list-unsubscribe: list-post: Errors-To: flx@namesys.com To: Horst von Brand In-Reply-To: <200409072102.i87L2K4u005503@laptop11.inf.utfsm.cl> List-Id: linux-fsdevel.vger.kernel.org > Hans Reiser said: >> Horst von Brand wrote: >> >Hans Reiser said: >> >>Horst von Brand wrote: >> >>>Spam said: >> >>>>Christer Weinigel said: > [...] >> >>>>>2. How do we want to expose named streams? >> >>>>> One suggestion is file-as-directory in some form. >> >>>Which is broken, as it forbids hard links to files. >> >>No, it forbids hard links to the directory aspect of the file-directory >> >>duality. >> >How do you distinguish a "hard link to the directory personality" from >> >"hard link to the file personality"? >> Put in (undoubtedly overly) simple terms, if you can do it to a file you >> can do it to the file personality, but if you currently can only do it >> to a directory and get an error from attempting it to a file then in the >> new scheme doing it to the hard link only gives the same error. > Let me sort this out: If it can't be done POSIXly to a directory, it can't > be done in Reiser4 to a file (which really is a directory too). So there > can be exactly _one_ hard link to a file. Way borken. But you can make a hard link to a file in reiser4, and you can access the metadata in both. I did this test: echo "moooo" > test ln test moo chmod +x moo test echo "0700" > test/metas/rwx dir moo test -rwx------ 2 root root 10 Sep 7 23:17 moo* -rwx------ 2 root root 10 Sep 7 23:17 test* echo "0777" > test/metas/rwx dir moo test -rwxrwxrwx 2 root root 10 Sep 7 23:17 moo* -rwxrwxrwx 2 root root 10 Sep 7 23:17 test* rm moo test mkdir test ln test moo ln: `test': hard link not allowed for directory If this is the intended behaviour I do not know, but it shows that hard links works as normal. You can also do linking to meta-data: echo moo > moo ln -s moo/metas/rwx test dir -rwxrwxrwx 1 root root 0 Sep 7 23:24 moo* lrwxrwxrwx 1 root root 13 Sep 7 23:25 test -> moo/metas/rwx echo 0700 > test dir moo -rwx------ 1 root root 0 Sep 7 23:24 moo* >> Or, we can ask Alexander to help us use his deadlock detection algorithm >> and try to do things right.... > Good luck with that one. I'd suspect if it can be made to work, it will > have _huge_ overhead, so much that it is useless. I'd love to be proven > wrong, but I won't hold my breath.