From mboxrd@z Thu Jan 1 00:00:00 1970 From: Felipe Alfaro Solana Subject: Re: silent semantic changes with reiser4 Date: Thu, 26 Aug 2004 16:39:45 +0200 Message-ID: <200408261639.46951.lkml@felipe-alfaro.com> References: <1453776111.20040826131547@tnonline.net> <1714037053.20040826155924@tnonline.net> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Cc: Rik van Riel , Andrew Morton , wichert@wiggy.net, jra@samba.org, torvalds@osdl.org, reiser@namesys.com, hch@lst.de, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, flx@namesys.com, reiserfs-list@namesys.com Return-path: list-help: list-unsubscribe: list-post: Errors-To: flx@namesys.com To: Spam In-Reply-To: <1714037053.20040826155924@tnonline.net> Content-Disposition: inline List-Id: linux-fsdevel.vger.kernel.org On Thursday 26 August 2004 15:59, Spam wrote: > Backup to me is a special case, not simply a copy of files, but also > retaining all the extra data, info, attributes, etc, that comes with > the file. > > Enabling support to have all of this extra stuff below the > application level it will be possible to retain everything even > though applications do not support them. > > Backup tools, however, must know about these new features to be able > to backup them. And so will every tool that directly accesses the > filesystem instead of using the OS API for it. Thus, this kind of metadata API must be made accessible through the VFS layer, if we want to make it FS-independent (not tied to Reiser4). If the real FS does not support metadata operations, just ignore them (much like in ISO9660 ignoring write operations). > And from I learned in an earlier message, tools like cp actually > work on the fs level and themselves move the data to the new file > instead of letting the OS handle it. This seem to me as it could > be dangerous and could also prevent any kind of enhancements to the > FS unless every tool like cp is patched. I still don't understand why a copy_file() syscall is still missing.