Re: [PATCH v2 8/9] iomap: Convert iomap_write_end types

[Darrick J. Wong]

On Fri, Sep 11, 2020 at 12:47:06AM +0100, Matthew Wilcox (Oracle) wrote:
> iomap_write_end cannot return an error, so switch it to return
> size_t instead of int and remove the error checking from the callers.
> Also convert the arguments to size_t from unsigned int, in case anyone
> ever wants to support a page size larger than 2GB.
> 
> Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
> Reviewed-by: Christoph Hellwig <hch@xxxxxx>

LGTM
Reviewed-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>

--D

> ---
>  fs/iomap/buffered-io.c | 31 ++++++++++++-------------------
>  1 file changed, 12 insertions(+), 19 deletions(-)
> 
> diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c
> index 64a5cb383f30..cb25a7b70401 100644
> --- a/fs/iomap/buffered-io.c
> +++ b/fs/iomap/buffered-io.c
> @@ -663,9 +663,8 @@ iomap_set_page_dirty(struct page *page)
>  }
>  EXPORT_SYMBOL_GPL(iomap_set_page_dirty);
>  
> -static int
> -__iomap_write_end(struct inode *inode, loff_t pos, unsigned len,
> -		unsigned copied, struct page *page)
> +static size_t __iomap_write_end(struct inode *inode, loff_t pos, size_t len,
> +		size_t copied, struct page *page)
>  {
>  	flush_dcache_page(page);
>  
> @@ -687,9 +686,8 @@ __iomap_write_end(struct inode *inode, loff_t pos, unsigned len,
>  	return copied;
>  }
>  
> -static int
> -iomap_write_end_inline(struct inode *inode, struct page *page,
> -		struct iomap *iomap, loff_t pos, unsigned copied)
> +static size_t iomap_write_end_inline(struct inode *inode, struct page *page,
> +		struct iomap *iomap, loff_t pos, size_t copied)
>  {
>  	void *addr;
>  
> @@ -705,13 +703,14 @@ iomap_write_end_inline(struct inode *inode, struct page *page,
>  	return copied;
>  }
>  
> -static int
> -iomap_write_end(struct inode *inode, loff_t pos, unsigned len, unsigned copied,
> -		struct page *page, struct iomap *iomap, struct iomap *srcmap)
> +/* Returns the number of bytes copied.  May be 0.  Cannot be an errno. */
> +static size_t iomap_write_end(struct inode *inode, loff_t pos, size_t len,
> +		size_t copied, struct page *page, struct iomap *iomap,
> +		struct iomap *srcmap)
>  {
>  	const struct iomap_page_ops *page_ops = iomap->page_ops;
>  	loff_t old_size = inode->i_size;
> -	int ret;
> +	size_t ret;
>  
>  	if (srcmap->type == IOMAP_INLINE) {
>  		ret = iomap_write_end_inline(inode, page, iomap, pos, copied);
> @@ -790,11 +789,8 @@ iomap_write_actor(struct inode *inode, loff_t pos, loff_t length, void *data,
>  
>  		copied = iov_iter_copy_from_user_atomic(page, i, offset, bytes);
>  
> -		status = iomap_write_end(inode, pos, bytes, copied, page, iomap,
> +		copied = iomap_write_end(inode, pos, bytes, copied, page, iomap,
>  				srcmap);
> -		if (unlikely(status < 0))
> -			break;
> -		copied = status;
>  
>  		cond_resched();
>  
> @@ -868,11 +864,8 @@ iomap_unshare_actor(struct inode *inode, loff_t pos, loff_t length, void *data,
>  
>  		status = iomap_write_end(inode, pos, bytes, bytes, page, iomap,
>  				srcmap);
> -		if (unlikely(status <= 0)) {
> -			if (WARN_ON_ONCE(status == 0))
> -				return -EIO;
> -			return status;
> -		}
> +		if (WARN_ON_ONCE(status == 0))
> +			return -EIO;
>  
>  		cond_resched();
>  
> -- 
> 2.28.0
>