Re: [PATCH 6/6] xfs: refactor xfs_file_fallocate

[Brian Foster <bfoster@redhat.com>]

On Wed, Aug 21, 2024 at 08:30:32AM +0200, Christoph Hellwig wrote:
> Refactor xfs_file_fallocate into separate helpers for each mode,
> two factors for i_size handling and a single switch statement over the
> supported modes.
> 
> Signed-off-by: Christoph Hellwig <hch@lst.de>
> ---
>  fs/xfs/xfs_file.c | 327 +++++++++++++++++++++++++++++-----------------
>  1 file changed, 205 insertions(+), 122 deletions(-)
> 
> diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
> index 489bc1b173c268..9d3bac7731bdcb 100644
> --- a/fs/xfs/xfs_file.c
> +++ b/fs/xfs/xfs_file.c
> @@ -852,6 +852,189 @@ static inline bool xfs_file_sync_writes(struct file *filp)
>  	return false;
>  }
>  
...
> +
> +static int
> +xfs_falloc_unshare_range(
> +	struct file		*file,
> +	int			mode,
> +	loff_t			offset,
> +	loff_t			len)
> +{
> +	struct inode		*inode = file_inode(file);
> +	loff_t			new_size = 0;
> +	int			error;
> +
> +	error = xfs_falloc_newsize(file, mode, offset, len, &new_size);
> +	if (error)
> +		return error;
> +
> +	error = xfs_reflink_unshare(XFS_I(inode), offset, len);
> +	if (error)
> +		return error;
> +

Doesn't unshare imply alloc?

> +	return xfs_falloc_setsize(file, new_size);
> +}
> +
...
> @@ -894,129 +1075,31 @@ xfs_file_fallocate(
>  	if (error)
>  		goto out_unlock;
>  
> -	if (mode & FALLOC_FL_PUNCH_HOLE) {
> +	switch (mode & FALLOC_FL_MODE_MASK) {
> +	case FALLOC_FL_PUNCH_HOLE:
>  		error = xfs_free_file_space(ip, offset, len);
...
> +		break;
> +	case FALLOC_FL_COLLAPSE_RANGE:
> +		error = xfs_falloc_collapse_range(file, offset, len);
> +		break;
> +	case FALLOC_FL_INSERT_RANGE:
> +		error = xfs_falloc_insert_range(file, offset, len);
> +		break;
> +	case FALLOC_FL_ZERO_RANGE:
> +		error = xfs_falloc_zero_range(file, mode, offset, len);
> +		break;
> +	case FALLOC_FL_UNSHARE_RANGE:
> +		error = xfs_falloc_unshare_range(file, mode, offset, len);
> +		break;
> +	case FALLOC_FL_ALLOCATE_RANGE:
> +		error = xfs_falloc_allocate_range(file, mode, offset, len);
> +		break;
> +	default:
> +		error = -EOPNOTSUPP;
> +		break;
>  	}
>  
> -	if (xfs_file_sync_writes(file))
> +	if (!error && xfs_file_sync_writes(file))
>  		error = xfs_log_force_inode(ip);

I'd think if you hit -ENOSPC or something after doing a partial alloc to
a sync inode, you'd still want to flush the changes that were made..?

Brian

>  
>  out_unlock:
> -- 
> 2.43.0
> 
>