Re: [PATCH 06/12] swap,block: move the block device swapon code into block/fops.c

["Darrick J. Wong" <djwong@kernel.org>]

On Tue, May 12, 2026 at 07:35:22AM +0200, Christoph Hellwig wrote:
> Make use of the abstractions we have.  This is a preparation for
> moving more special casing down into block/.
> 
> Signed-off-by: Christoph Hellwig <hch@lst.de>

Nice straightforward hoist.

Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>

--D

> ---
>  block/fops.c  | 6 ++++++
>  mm/swapfile.c | 5 -----
>  2 files changed, 6 insertions(+), 5 deletions(-)
> 
> diff --git a/block/fops.c b/block/fops.c
> index bb6642b45937..453141801684 100644
> --- a/block/fops.c
> +++ b/block/fops.c
> @@ -949,6 +949,11 @@ static int blkdev_mmap_prepare(struct vm_area_desc *desc)
>  	return generic_file_mmap_prepare(desc);
>  }
>  
> +static int blkdev_swap_activate(struct file *file, struct swap_info_struct *sis)
> +{
> +	return add_swap_extent(sis, sis->max, 0);
> +}
> +
>  const struct file_operations def_blk_fops = {
>  	.open		= blkdev_open,
>  	.release	= blkdev_release,
> @@ -965,6 +970,7 @@ const struct file_operations def_blk_fops = {
>  	.splice_read	= filemap_splice_read,
>  	.splice_write	= iter_file_splice_write,
>  	.fallocate	= blkdev_fallocate,
> +	.swap_activate	= blkdev_swap_activate,
>  	.uring_cmd	= blkdev_uring_cmd,
>  	.fop_flags	= FOP_BUFFER_RASYNC,
>  };
> diff --git a/mm/swapfile.c b/mm/swapfile.c
> index 1b7fc03612f4..fbf11c8c5c69 100644
> --- a/mm/swapfile.c
> +++ b/mm/swapfile.c
> @@ -2781,13 +2781,8 @@ EXPORT_SYMBOL_GPL(add_swap_extent);
>  static int setup_swap_extents(struct swap_info_struct *sis,
>  			      struct file *swap_file)
>  {
> -	struct address_space *mapping = swap_file->f_mapping;
> -	struct inode *inode = mapping->host;
>  	int ret, error = 0;
>  
> -	if (S_ISBLK(inode->i_mode))
> -		return add_swap_extent(sis, sis->max, 0);
> -
>  	if (swap_file->f_op->swap_activate)
>  		ret = swap_file->f_op->swap_activate(swap_file, sis);
>  	else
> -- 
> 2.53.0
> 
>