From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Vladimir V. Saveliev" Subject: Re: keys and inodes Date: Sun, 04 Jul 2004 12:46:26 +0400 Message-ID: <40E7C3E2.10509@namesys.com> References: <1088802102.6434.80.camel@murdock.llnl.gov> <40E67C3D.6070609@namesys.com> <200407031650.55869.marcelo@macp.eti.br> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: list-help: list-unsubscribe: list-post: Errors-To: flx@namesys.com In-Reply-To: <200407031650.55869.marcelo@macp.eti.br> List-Id: Content-Type: text/plain; charset="us-ascii"; format="flowed" To: Marcelo Pacheco Cc: reiserfs-list@namesys.com Hello Marcelo Pacheco wrote: > So, inode numbers on Reiser are alocated on the fly, as files are used, and > those numbers will change, so for example, ls -i is useless with reiser, as > that number given for each file will change once the vfs structure gets > released and later the file gets used again ? > No, once file is created ls -i will always return the same inode number for it. > Just checking, > > Marcelo Pacheco > > On Saturday 03 July 2004 06:28, Vladimir V. Saveliev wrote: > >>Hello >> >>jenn sirp wrote: >> >>>Hi, >>> >>>I was hoping someone might be able to answer a couple of questions about >>>inodes is Reiser(v3). >>> >>>I would like to know how ReiserFS inodes and the VFS inodes in the >>>d_cache correspond with each other. >> >>You might want to read about dentry-inode relationship in >>linux/Documentation/filesystem/vfs.txt. >> >> Specifically, how and where it is >> >> >>>that 'keys' get mapped to inodes in the system? >> >>Reiserfs provides set of vfs operations. The one which is responsible >>for mapping keys to inode is lookup method. reiserfs implementation is >>reiserfs_lookup. It searches for the file name in filesystem tree. If >>name is found - file key is extracted from it and VFS inode is created >>(connected to d_cache dentry). >>File key is stored in reiserfs specific portion of VFS inode. >> >> >>>Do ReiserFS keys change or get reconstructed when tails are packed or >>>when the tree gets re-balanced? >> >>No. Once file is created - its key never changes. However, each position >>in a file has its own key. For instance, 0-th byte of a file has key X, >>Y, 1. 100-th byte of a file should be looked for with key X, Y, 101. >>[X, Y] is the same for any part of file. This is what is extracted from >>file name on lookup. Key of any other position within a file can be >>easily calculated as we saw. >> >>Or do keys remain consistent throughout >> >> >>>a file's lifetime in the system? >> >>Yes. >> >> >>>Even the quickest response would be greatly appreciated. >>> >>>Thanks, >>> >>>Jenn > > >