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

Theodore Tso
2008-01-26T04:15:30Z

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);
+ return retval;
+}

- Ted