From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ronghua Zhang <rz5b@cs.virginia.edu>
Subject: Re: problems in implementing a new file system
Date: Mon, 17 Feb 2003 17:53:29 -0500 (EST)
Sender: linux-fsdevel-owner@vger.kernel.org
Message-ID: <Pine.GSO.4.51.0302171748490.13225@mamba.cs.Virginia.EDU>
References: <Pine.GSO.4.51.0302171727420.13225@mamba.cs.Virginia.EDU>
Mime-Version: 1.0
Content-Type: TEXT/PLAIN; charset=US-ASCII
Return-path: <linux-fsdevel-owner@vger.kernel.org>
To: linux-fsdevel@vger.kernel.org, kernelnewbies@nl.linux.org
In-Reply-To: <Pine.GSO.4.51.0302171727420.13225@mamba.cs.Virginia.EDU>
List-Id: linux-fsdevel.vger.kernel.org

Oh, I just forgot to mention that the kernel is 2.4.19 and gcc version is
3.2. I also used uml to trace it, and I found that the 'magic' happens
within get_new_inode():
....
inode->i_sb = sb;
...
if (sb->s_op->read_inode2) sb->s_op->read_inode2(inode, opaque);
else sb->s_op->read_inode(inode);

just before sb->s_op_read_inode() is executed, inode->i_sb is still sb.
But once the function (which is snet_read_inode()) is called, inode->i_sb
just magically point to some other place.

rz