From: "Anthony Chee" <anthony.chee@polyu.edu.hk>
Subject: Question on deleting file
Date: Tue, 9 Apr 2002 10:38:30 +0800
Sender: linux-fsdevel-owner@vger.kernel.org
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I made some modification inode.c for my purpose. I defined myfunc() for my
own use

I modified write_inode as following. My purpose is to use a function to
determine such inode should pass to lower to lower file system (ext2, vfat,
etc) for writing on disk.

static inline void write_inode(struct inode *inode, int sync)
{
    if (myfunc() == 0) {
              if (inode->i_sb && inode->i_sb->s_op &&
inode->i_sb->s_op->write_inode && !is_bad_inode(inode)) {
                    inode->i_sb->s_op->write_inode(inode, sync);

  } else {
            if (inode->i_sb && inode->i_sb->s_op &&
inode->i_sb->s_op->write_inode && !is_bad_inode(inode)) {
                    inode->i_sb->s_op->write_inode(inode, sync);
            die(inode);
  }
 }
}

static inline void die(inode) {
    iput(inode);
}

I used iput(inode) in this case. Is it right? I supposed the inode will
immediatly deleted after written on disk, and release the block used. But I
found that I still can see such file when I press "ls".
I also tried to add inode->i_nlink = 0 and atomic_set(&inode->i_count, 0) in
die(inode) function before iput(inode), but not success. It may also have
input/output error on that file after I reboot system and "ls".

Or any method to drop the inode (do not pass to lower file system layer,
just delete it in VFS layer) when myfunc() != 0?

Any one can give suggestion on it? Thanks for help. :D