On Mon 22-05-17 18:34:41, Eric Biggers wrote:
> From: Eric Biggers <ebiggers@xxxxxxxxxx>
>
> The 'lend' argument of filemap_write_and_wait_range() is inclusive, so
> we need to subtract 1 from pos + count.
>
> Note that 'count' is guaranteed to be nonzero since
> ext4_file_read_iter() returns early when given a 0 count.
>
> Fixes: 16c54688592c ("ext4: Allow parallel DIO reads")
> Signed-off-by: Eric Biggers <ebiggers@xxxxxxxxxx>
Yeah. You can add:
Reviewed-by: Jan Kara <jack@xxxxxxx>
Honza
> ---
> fs/ext4/inode.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
> index 7c6e715b4d2e..3080ea82dd6d 100644
> --- a/fs/ext4/inode.c
> +++ b/fs/ext4/inode.c
> @@ -3710,7 +3710,7 @@ static ssize_t ext4_direct_IO_read(struct kiocb *iocb, struct iov_iter *iter)
> */
> inode_lock_shared(inode);
> ret = filemap_write_and_wait_range(mapping, iocb->ki_pos,
> - iocb->ki_pos + count);
> + iocb->ki_pos + count - 1);
> if (ret)
> goto out_unlock;
> ret = __blockdev_direct_IO(iocb, inode, inode->i_sb->s_bdev,
> --
> 2.13.0.219.gdb65acc882-goog
>
--
Jan Kara <jack@xxxxxxxx>
SUSE Labs, CR
