[Cluster-devel] [GFS2 PATCH] gfs2: Combine transaction from gfs2_dir_exhash_dealloc

[Steven Whitehouse <swhiteho@redhat.com>]

Hi,

Looks good,

Steve.

On Tue, 2011-03-22 at 13:54 -0400, Bob Peterson wrote:
> Hi,
> 
> At the end of function gfs2_dir_exhash_dealloc, it was setting the dinode
> type to "file" to prevent directory corruption in case of a crash.
> It was doing so in its own journal transaction.  This patch makes the
> change occur when the last call is make to leaf_dealloc, since it needs
> to rewrite the directory dinode at that time anyway.
> 
> Regards,
> 
> Bob Peterson
> Red Hat File Systems
> 
> Signed-off-by: Bob Peterson <rpeterso@redhat.com> 
> --
> diff --git a/fs/gfs2/dir.c b/fs/gfs2/dir.c
> index 10a4bbe..6791e49 100644
> --- a/fs/gfs2/dir.c
> +++ b/fs/gfs2/dir.c
> @@ -86,7 +86,7 @@ typedef int (*gfs2_dscan_t)(const struct gfs2_dirent *dent,
>  			    const struct qstr *name, void *opaque);
>  
>  static int leaf_dealloc(struct gfs2_inode *dip, u32 index, u32 len,
> -			u64 leaf_no);
> +			u64 leaf_no, int last_dealloc);
>  
>  int gfs2_dir_get_new_buffer(struct gfs2_inode *ip, u64 block,
>  			    struct buffer_head **bhp)
> @@ -1781,10 +1781,10 @@ static int foreach_leaf(struct gfs2_inode *dip)
>  	struct gfs2_leaf *leaf;
>  	u32 hsize, len;
>  	u32 ht_offset, lp_offset, ht_offset_cur = -1;
> -	u32 index = 0;
> +	u32 index = 0, next_index;
>  	__be64 *lp;
>  	u64 leaf_no;
> -	int error = 0;
> +	int error = 0, last;
>  
>  	hsize = 1 << dip->i_depth;
>  	if (hsize * sizeof(u64) != i_size_read(&dip->i_inode)) {
> @@ -1819,13 +1819,13 @@ static int foreach_leaf(struct gfs2_inode *dip)
>  				goto out;
>  			leaf = (struct gfs2_leaf *)bh->b_data;
>  			len = 1 << (dip->i_depth - be16_to_cpu(leaf->lf_depth));
> +			next_index = (index & ~(len - 1)) + len;
> +			last = ((next_index >= hsize) ? 1 : 0);
>  			brelse(bh);
> -
> -			error = leaf_dealloc(dip, index, len, leaf_no);
> +			error = leaf_dealloc(dip, index, len, leaf_no, last);
>  			if (error)
>  				goto out;
> -
> -			index = (index & ~(len - 1)) + len;
> +			index = next_index;
>  		} else
>  			index++;
>  	}
> @@ -1847,13 +1847,13 @@ out:
>   * @index: the hash table offset in the directory
>   * @len: the number of pointers to this leaf
>   * @leaf_no: the leaf number
> - * @data: not used
> + * last_dealloc: 1 if this is the final dealloc for the leaf, else 0
>   *
>   * Returns: errno
>   */
>  
>  static int leaf_dealloc(struct gfs2_inode *dip, u32 index, u32 len,
> -			u64 leaf_no)
> +			u64 leaf_no, int last_dealloc)
>  {
>  	struct gfs2_sbd *sdp = GFS2_SB(&dip->i_inode);
>  	struct gfs2_leaf *tmp_leaf;
> @@ -1940,6 +1940,10 @@ static int leaf_dealloc(struct gfs2_inode *dip, u32 index, u32 len,
>  		goto out_end_trans;
>  
>  	gfs2_trans_add_bh(dip->i_gl, dibh, 1);
> +	/* On the last dealloc, make this a regular file in case we crash.
> +	   (We don't want to free these blocks a second time.)  */
> +	if (last_dealloc)
> +		dip->i_inode.i_mode = S_IFREG;
>  	gfs2_dinode_out(dip, dibh->b_data);
>  	brelse(dibh);
>  
> @@ -1971,33 +1975,8 @@ out:
>  
>  int gfs2_dir_exhash_dealloc(struct gfs2_inode *dip)
>  {
> -	struct gfs2_sbd *sdp = GFS2_SB(&dip->i_inode);
> -	struct buffer_head *bh;
> -	int error;
> -
>  	/* Dealloc on-disk leaves to FREEMETA state */
> -	error = foreach_leaf(dip);
> -	if (error)
> -		return error;
> -
> -	/* Make this a regular file in case we crash.
> -	   (We don't want to free these blocks a second time.)  */
> -
> -	error = gfs2_trans_begin(sdp, RES_DINODE, 0);
> -	if (error)
> -		return error;
> -
> -	error = gfs2_meta_inode_buffer(dip, &bh);
> -	if (!error) {
> -		gfs2_trans_add_bh(dip->i_gl, bh, 1);
> -		((struct gfs2_dinode *)bh->b_data)->di_mode =
> -						cpu_to_be32(S_IFREG);
> -		brelse(bh);
> -	}
> -
> -	gfs2_trans_end(sdp);
> -
> -	return error;
> +	return foreach_leaf(dip);
>  }
>  
>  /**
>