Re: [PATCH 1/2] f2fs: fix to preallocate block only aligned to 4K

[Chao Yu <yuchao0@huawei.com>]

Hi Jaegeuk,

On 2016/8/24 7:19, Jaegeuk Kim wrote:
> Hi Chao,
> 
> There is a bug when ki_pos = 1024, and iov_iter_count(from) = 1024 in xfstests.
> Could you check the below patch to fix your one?

Oh, you're right, thanks for fixing it. :)

Thanks,

> 
> ---
>  fs/f2fs/data.c | 11 +++++++++--
>  1 file changed, 9 insertions(+), 2 deletions(-)
> 
> diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
> index 37a59f7..7c8e219 100644
> --- a/fs/f2fs/data.c
> +++ b/fs/f2fs/data.c
> @@ -626,8 +626,12 @@ ssize_t f2fs_preallocate_blocks(struct kiocb *iocb, struct iov_iter *from)
>  	ssize_t ret = 0;
>  
>  	map.m_lblk = F2FS_BLK_ALIGN(iocb->ki_pos);
> -	map.m_len = F2FS_BYTES_TO_BLK(iocb->ki_pos + iov_iter_count(from)) -
> -								map.m_lblk;
> +	map.m_len = F2FS_BYTES_TO_BLK(iocb->ki_pos + iov_iter_count(from));
> +	if (map.m_len > map.m_lblk)
> +		map.m_len -= map.m_lblk;
> +	else
> +		map.m_len = 0;
> +
>  	map.m_next_pgofs = NULL;
>  
>  	if (f2fs_encrypted_inode(inode))
> @@ -673,6 +677,9 @@ int f2fs_map_blocks(struct inode *inode, struct f2fs_map_blocks *map,
>  	bool allocated = false;
>  	block_t blkaddr;
>  
> +	if (!maxblocks)
> +		return 0;
> +
>  	map->m_len = 0;
>  	map->m_flags = 0;
>  
>