Re: [PATCH 01/10] ext4: add did_zero output parameter to ext4_block_zero_page_range()

[Jan Kara]

On Tue 10-03-26 09:40:52, Zhang Yi wrote:
> From: Zhang Yi <yi.zhang@xxxxxxxxxx>
> 
> Add a bool *did_zero output parameter to ext4_block_zero_page_range()
> and __ext4_block_zero_page_range(). The parameter reports whether a
> partial block was zeroed out, which is needed for the upcoming iomap
> buffered I/O conversion.
> 
> Signed-off-by: Zhang Yi <yi.zhang@xxxxxxxxxx>

Looks good. Feel free to add:

Reviewed-by: Jan Kara <jack@xxxxxxx>

								Honza

> ---
>  fs/ext4/inode.c | 23 ++++++++++++++---------
>  1 file changed, 14 insertions(+), 9 deletions(-)
> 
> diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
> index 396dc3a5d16b..1e037a314dab 100644
> --- a/fs/ext4/inode.c
> +++ b/fs/ext4/inode.c
> @@ -4003,7 +4003,8 @@ void ext4_set_aops(struct inode *inode)
>   * racing writeback can come later and flush the stale pagecache to disk.
>   */
>  static int __ext4_block_zero_page_range(handle_t *handle,
> -		struct address_space *mapping, loff_t from, loff_t length)
> +		struct address_space *mapping, loff_t from, loff_t length,
> +		bool *did_zero)
>  {
>  	unsigned int offset, blocksize, pos;
>  	ext4_lblk_t iblock;
> @@ -4091,6 +4092,8 @@ static int __ext4_block_zero_page_range(handle_t *handle,
>  			err = ext4_jbd2_inode_add_write(handle, inode, from,
>  					length);
>  	}
> +	if (!err && did_zero)
> +		*did_zero = true;
>  
>  unlock:
>  	folio_unlock(folio);
> @@ -4106,7 +4109,8 @@ static int __ext4_block_zero_page_range(handle_t *handle,
>   * that corresponds to 'from'
>   */
>  static int ext4_block_zero_page_range(handle_t *handle,
> -		struct address_space *mapping, loff_t from, loff_t length)
> +		struct address_space *mapping, loff_t from, loff_t length,
> +		bool *did_zero)
>  {
>  	struct inode *inode = mapping->host;
>  	unsigned blocksize = inode->i_sb->s_blocksize;
> @@ -4120,10 +4124,11 @@ static int ext4_block_zero_page_range(handle_t *handle,
>  		length = max;
>  
>  	if (IS_DAX(inode)) {
> -		return dax_zero_range(inode, from, length, NULL,
> +		return dax_zero_range(inode, from, length, did_zero,
>  				      &ext4_iomap_ops);
>  	}
> -	return __ext4_block_zero_page_range(handle, mapping, from, length);
> +	return __ext4_block_zero_page_range(handle, mapping, from, length,
> +					    did_zero);
>  }
>  
>  /*
> @@ -4146,7 +4151,7 @@ static int ext4_block_truncate_page(handle_t *handle,
>  	blocksize = i_blocksize(inode);
>  	length = blocksize - (from & (blocksize - 1));
>  
> -	return ext4_block_zero_page_range(handle, mapping, from, length);
> +	return ext4_block_zero_page_range(handle, mapping, from, length, NULL);
>  }
>  
>  int ext4_zero_partial_blocks(handle_t *handle, struct inode *inode,
> @@ -4169,13 +4174,13 @@ int ext4_zero_partial_blocks(handle_t *handle, struct inode *inode,
>  	if (start == end &&
>  	    (partial_start || (partial_end != sb->s_blocksize - 1))) {
>  		err = ext4_block_zero_page_range(handle, mapping,
> -						 lstart, length);
> +						 lstart, length, NULL);
>  		return err;
>  	}
>  	/* Handle partial zero out on the start of the range */
>  	if (partial_start) {
> -		err = ext4_block_zero_page_range(handle, mapping,
> -						 lstart, sb->s_blocksize);
> +		err = ext4_block_zero_page_range(handle, mapping, lstart,
> +						 sb->s_blocksize, NULL);
>  		if (err)
>  			return err;
>  	}
> @@ -4183,7 +4188,7 @@ int ext4_zero_partial_blocks(handle_t *handle, struct inode *inode,
>  	if (partial_end != sb->s_blocksize - 1)
>  		err = ext4_block_zero_page_range(handle, mapping,
>  						 byte_end - partial_end,
> -						 partial_end + 1);
> +						 partial_end + 1, NULL);
>  	return err;
>  }
>  
> -- 
> 2.52.0
> 
-- 
Jan Kara <jack@xxxxxxxx>
SUSE Labs, CR