From mboxrd@z Thu Jan 1 00:00:00 1970 From: Edward Shishkin Subject: Re: The... reiser4 with no ambiguity Date: Sun, 14 Dec 2008 22:17:04 +0300 Message-ID: <49455BB0.7000300@gmail.com> References: <494035ED.4000706@gmx.de> <49404165.6050806@gmail.com> <49405D98.7000402@gmx.de> <4941467B.30308@gmail.com> <49414FC3.1040206@gmx.de> <494157FD.5020708@gmail.com> <49419A90.4020906@gmail.com> <49440D64.9050900@gmail.com> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: reiserfs-devel-owner@vger.kernel.org List-ID: Content-Type: text/plain; charset="us-ascii" To: Ralph Ulrich Cc: reiserfs-devel@vger.kernel.org Ralph Ulrich wrote: > Edward Shishkin Samstag 13 Dezember 2008 20:30: > >> I don't know such vfs doctrine. Who is the keeper of this doctrine? >> :-))) >> > Please, do not be too ironicle here, because I am not an insider and english is not my motherlanguage. I meant there was a discussion that in the linux mainline kernel there should not be a filesystem which has files that can have files. A file as directory was introduced to unifiy namespace by namesys. > > >> Subfiles mean one more step in the procedure of name resolution. >> You should return an allocated inode to vfs for every such subfile. >> So subfiles also can not be hidden. There is a temptation to cheat >> vfs, so it will think that it deals with usual files, but such >> cheating doesn't lead to happy end.. >> >> xattrs is ugly, but working solution, >> subfiles are nice, but it doesn't work.. ;) >> > > First of all I have to understand reiser4 with no ambiguity: > > Are reiser4 file-plugins _only_ to handle data effective at low-level (like your compression plugin). Nop. There can be new features, which . come from vfs; . are not related to data storage improvements; . require a new reiser4 plugin. A good example - xattrs. > I know you stress this quiet often in your mails. Or is it just your focussing for now to get reiser4 mainline? > > Is it not possible to introduce new extended features in reiser4 and hide these features vfs? > Yes, it is possible, but, again, those features should implement some new (optimal, efficient, safe, reliable, etc.) form of data storage. > In reiser4 there is no such possibility to introduce a new kind of file which is hidden from vfs? > Yes, it is. For example, there are two regular file plugins in reiser4. Both are intensively used, but vfs doesn't know about them. > Semantics of reiser5 are totally out of scope here, but I thought of them as implementable above/on reiser4 Yes, I have pushed some technical concepts of r5 to r4 a year ago.. > - reiser4 as the technical grounds for reiser5 (as announced by namesys). > > Ralph > > -- > To unsubscribe from this list: send the line "unsubscribe reiserfs-devel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > >