From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Peter Teoh" Subject: Re: "Write once only but read many" filesystem Date: Sat, 22 Mar 2008 23:55:53 +0800 Message-ID: <804dabb00803220855q1aa41fc7mc30c7ce7951fe98@mail.gmail.com> References: <804dabb00803140917o2abebd2dh12c77b21a48094c4@mail.gmail.com> <20080314232403.GI3542@webber.adilger.int> <47E48D84.7070701@gmail.com> <20080322102331.GA19347@logfs.org> <804dabb00803220752h670757d8o9c1b7fa3696467bc@mail.gmail.com> <20080322150626.GB19347@logfs.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: kernelnewbies , linux-fsdevel@vger.kernel.org, ext3-users@redhat.com To: "=?ISO-8859-1?Q?J=F6rn_Engel?=" Return-path: Received: from wf-out-1314.google.com ([209.85.200.173]:44262 "EHLO wf-out-1314.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750898AbYCVPzy convert rfc822-to-8bit (ORCPT ); Sat, 22 Mar 2008 11:55:54 -0400 Received: by wf-out-1314.google.com with SMTP id 28so2109490wff.4 for ; Sat, 22 Mar 2008 08:55:53 -0700 (PDT) In-Reply-To: <20080322150626.GB19347@logfs.org> Content-Disposition: inline Sender: linux-fsdevel-owner@vger.kernel.org List-ID: Thank you for your reply :-). On Sat, Mar 22, 2008 at 11:06 PM, J=F6rn Engel wrote: > On Sat, 22 March 2008 22:52:12 +0800, Peter Teoh wrote: > > > > what are the difference in terms of final features provided by the= se > > two different filesystem? what is this "garbage collection"? u > > still have features like creating different directories, and creat= ing > > different files, and writing the files? How about setting the fi= le > > attributes...it should be set before writing right (so that after > > writing and handle is closed it becomes permanently not > > modifiable)..but creating a subdirectory below the current dir sho= uld > > be possible right (even after closing the previous directory)? > > Your requirements aren't quite clear to me. Do you want the complet= e > filesystem to be read-only after being written once? YES.... > Or do you want individual files/directories to be immutable - chatt= r? chattr is not good enough, as root can still modify it. So if current feature is not there, then some small development may be needed. > And in either case, what problem do you want to solve with a read-on= ly filesystem? Simple: i want to record down everything that a user does, or a database does, or any applications running - just record down its state permanently securely into the filesystem, knowing that for sure, there is not way to modify the data, short of recreating the filesystem again. Sound logical? Or is there any loophole in this concept? In summary, are there any strong demand for such a concept/filesystem? I may take the plunge to implementing it, if justfiable and everybody is interested..:-)... --=20 Regards, Peter Teoh -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel= " in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html