Re: [PATCH v3 1/3] NFS: Rename readpage_async_filler to nfs_pageio_add_page

[Jeff Layton <jlayton@kernel.org>]

On Tue, 2022-08-30 at 20:50 -0400, Dave Wysochanski wrote:
> Rename readpage_async_filler to nfs_pageio_add_page to
> better reflect what this function does (add a page to
> the nfs_pageio_descriptor), and simplify arguments to
> this function by removing struct nfs_readdesc.
> 
> Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
> ---
>  fs/nfs/read.c | 60 +++++++++++++++++++++++++--------------------------
>  1 file changed, 30 insertions(+), 30 deletions(-)
> 
> diff --git a/fs/nfs/read.c b/fs/nfs/read.c
> index 8ae2c8d1219d..525e82ea9a9e 100644
> --- a/fs/nfs/read.c
> +++ b/fs/nfs/read.c
> @@ -127,11 +127,6 @@ static void nfs_readpage_release(struct nfs_page *req, int error)
>  	nfs_release_request(req);
>  }
>  
> -struct nfs_readdesc {
> -	struct nfs_pageio_descriptor pgio;
> -	struct nfs_open_context *ctx;
> -};
> -
>  static void nfs_page_group_set_uptodate(struct nfs_page *req)
>  {
>  	if (nfs_page_group_sync_on_bit(req, PG_UPTODATE))
> @@ -153,7 +148,8 @@ static void nfs_read_completion(struct nfs_pgio_header *hdr)
>  
>  		if (test_bit(NFS_IOHDR_EOF, &hdr->flags)) {
>  			/* note: regions of the page not covered by a
> -			 * request are zeroed in readpage_async_filler */
> +			 * request are zeroed in nfs_pageio_add_page
> +			 */
>  			if (bytes > hdr->good_bytes) {
>  				/* nothing in this request was good, so zero
>  				 * the full extent of the request */
> @@ -281,8 +277,10 @@ static void nfs_readpage_result(struct rpc_task *task,
>  		nfs_readpage_retry(task, hdr);
>  }
>  
> -static int
> -readpage_async_filler(struct nfs_readdesc *desc, struct page *page)
> +int
> +nfs_pageio_add_page(struct nfs_pageio_descriptor *pgio,
> +		    struct nfs_open_context *ctx,
> +		    struct page *page)
>  {
>  	struct inode *inode = page_file_mapping(page)->host;
>  	unsigned int rsize = NFS_SERVER(inode)->rsize;
> @@ -302,15 +300,15 @@ readpage_async_filler(struct nfs_readdesc *desc, struct page *page)
>  			goto out_unlock;
>  	}
>  
> -	new = nfs_create_request(desc->ctx, page, 0, aligned_len);
> +	new = nfs_create_request(ctx, page, 0, aligned_len);
>  	if (IS_ERR(new))
>  		goto out_error;
>  
>  	if (len < PAGE_SIZE)
>  		zero_user_segment(page, len, PAGE_SIZE);
> -	if (!nfs_pageio_add_request(&desc->pgio, new)) {
> +	if (!nfs_pageio_add_request(pgio, new)) {
>  		nfs_list_remove_request(new);
> -		error = desc->pgio.pg_error;
> +		error = pgio->pg_error;
>  		nfs_readpage_release(new, error);
>  		goto out;
>  	}
> @@ -332,7 +330,8 @@ readpage_async_filler(struct nfs_readdesc *desc, struct page *page)
>  int nfs_read_folio(struct file *file, struct folio *folio)
>  {
>  	struct page *page = &folio->page;
> -	struct nfs_readdesc desc;
> +	struct nfs_pageio_descriptor pgio;
> +	struct nfs_open_context *ctx;
>  	struct inode *inode = page_file_mapping(page)->host;
>  	int ret;
>  
> @@ -358,29 +357,29 @@ int nfs_read_folio(struct file *file, struct folio *folio)
>  
>  	if (file == NULL) {
>  		ret = -EBADF;
> -		desc.ctx = nfs_find_open_context(inode, NULL, FMODE_READ);
> -		if (desc.ctx == NULL)
> +		ctx = nfs_find_open_context(inode, NULL, FMODE_READ);
> +		if (ctx == NULL)
>  			goto out_unlock;
>  	} else
> -		desc.ctx = get_nfs_open_context(nfs_file_open_context(file));
> +		ctx = get_nfs_open_context(nfs_file_open_context(file));
>  
> -	xchg(&desc.ctx->error, 0);
> -	nfs_pageio_init_read(&desc.pgio, inode, false,
> +	xchg(&ctx->error, 0);
> +	nfs_pageio_init_read(&pgio, inode, false,
>  			     &nfs_async_read_completion_ops);
>  
> -	ret = readpage_async_filler(&desc, page);
> +	ret = nfs_pageio_add_page(&pgio, ctx, page);
>  	if (ret)
>  		goto out;
>  
> -	nfs_pageio_complete_read(&desc.pgio);
> -	ret = desc.pgio.pg_error < 0 ? desc.pgio.pg_error : 0;
> +	nfs_pageio_complete_read(&pgio);
> +	ret = pgio.pg_error < 0 ? pgio.pg_error : 0;
>  	if (!ret) {
>  		ret = wait_on_page_locked_killable(page);
>  		if (!PageUptodate(page) && !ret)
> -			ret = xchg(&desc.ctx->error, 0);
> +			ret = xchg(&ctx->error, 0);
>  	}
>  out:
> -	put_nfs_open_context(desc.ctx);
> +	put_nfs_open_context(ctx);
>  	trace_nfs_aop_readpage_done(inode, page, ret);
>  	return ret;
>  out_unlock:
> @@ -391,9 +390,10 @@ int nfs_read_folio(struct file *file, struct folio *folio)
>  
>  void nfs_readahead(struct readahead_control *ractl)
>  {
> +	struct nfs_pageio_descriptor pgio;
> +	struct nfs_open_context *ctx;
>  	unsigned int nr_pages = readahead_count(ractl);
>  	struct file *file = ractl->file;
> -	struct nfs_readdesc desc;
>  	struct inode *inode = ractl->mapping->host;
>  	struct page *page;
>  	int ret;
> @@ -407,25 +407,25 @@ void nfs_readahead(struct readahead_control *ractl)
>  
>  	if (file == NULL) {
>  		ret = -EBADF;
> -		desc.ctx = nfs_find_open_context(inode, NULL, FMODE_READ);
> -		if (desc.ctx == NULL)
> +		ctx = nfs_find_open_context(inode, NULL, FMODE_READ);
> +		if (ctx == NULL)
>  			goto out;
>  	} else
> -		desc.ctx = get_nfs_open_context(nfs_file_open_context(file));
> +		ctx = get_nfs_open_context(nfs_file_open_context(file));
>  
> -	nfs_pageio_init_read(&desc.pgio, inode, false,
> +	nfs_pageio_init_read(&pgio, inode, false,
>  			     &nfs_async_read_completion_ops);
>  
>  	while ((page = readahead_page(ractl)) != NULL) {
> -		ret = readpage_async_filler(&desc, page);
> +		ret = nfs_pageio_add_page(&pgio, ctx, page);
>  		put_page(page);
>  		if (ret)
>  			break;
>  	}
>  
> -	nfs_pageio_complete_read(&desc.pgio);
> +	nfs_pageio_complete_read(&pgio);
>  
> -	put_nfs_open_context(desc.ctx);
> +	put_nfs_open_context(ctx);
>  out:
>  	trace_nfs_aop_readahead_done(inode, nr_pages, ret);
>  }

Yeah, a special args struct only with 2 fields in it does seem sort of
pointless:

Reviewed-by: Jeff Layton <jlayton@kernel.org>