Re: [PATCH 36/49] ext4: Add EXT4_IOC_MIGRATE ioctl

Aneesh Kumar K.V
2008-01-26T08:42:59Z

On Fri, Jan 25, 2008 at 11:15:00PM -0500, Theodore Tso wrote:
> On Thu, Jan 24, 2008 at 11:25:32AM +0530, Aneesh Kumar K.V wrote:
> > +static int free_ext_idx(handle_t *handle, struct inode *inode,
> > + struct ext4_extent_idx *ix)
> > +{
> > + int i, retval = 0;
> > + ext4_fsblk_t block;
> > + struct buffer_head *bh;
> > + struct ext4_extent_header *eh;
> > +
> > + block = idx_pblock(ix);
> > + bh = sb_bread(inode->i_sb, block);
> > + if (!bh)
> > + return -EIO;
> > +
> > + eh = (struct ext4_extent_header *)bh->b_data;
> > + if (eh->eh_depth == 0) {
> > + brelse(bh);
> > + ext4_free_blocks(handle, inode, block, 1);
> > + } else {
> > + ix = EXT_FIRST_INDEX(eh);
> > + for (i = 0; i < le16_to_cpu(eh->eh_entries); i++, ix++) {
> > + retval = free_ext_idx(handle, inode, ix);
> > + if (retval)
> > + return retval;
> > + }
> > + }
> > + return retval;
> > +}
>
> Aneesh, looks like if eh->eh_depth is != 0, bh gets leaked. This is
> how I plan to fix it up:
>
> +static int free_ext_idx(handle_t *handle, struct inode *inode,
> + struct ext4_extent_idx *ix)
> +{
> + int i, retval = 0;
> + ext4_fsblk_t block;
> + struct buffer_head *bh;
> + struct ext4_extent_header *eh;
> +
> + block = idx_pblock(ix);
> + bh = sb_bread(inode->i_sb, block);
> + if (!bh)
> + return -EIO;
> +
> + eh = (struct ext4_extent_header *)bh->b_data;
> + if (eh->eh_depth == 0)
> + ext4_free_blocks(handle, inode, block, 1);
> + else {
> + ix = EXT_FIRST_INDEX(eh);
> + for (i = 0; i < le16_to_cpu(eh->eh_entries); i++, ix++) {
> + retval = free_ext_idx(handle, inode, ix);
> + if (retval)
> + break;
> + }
> + }
> + put_bh(bh);

We need to mark the index block as free.
via ext4_free_blocks(handle, inode, block, 1);

I remember making this change. May be it was related to dind/tind
blocks.

-aneesh