Re: [PATCH v3 7/7] cachefiles: use kiocb_{start,end}_write() helpers

[Jan Kara <jack@suse.cz>]

On Thu 17-08-23 17:13:37, Amir Goldstein wrote:
> Use helpers instead of the open coded dance to silence lockdep warnings.
> 
> Suggested-by: Jan Kara <jack@suse.cz>
> Signed-off-by: Amir Goldstein <amir73il@gmail.com>

Looks good. Feel free to add:

Reviewed-by: Jan Kara <jack@suse.cz>

								Honza

> ---
>  fs/cachefiles/io.c | 16 +++-------------
>  1 file changed, 3 insertions(+), 13 deletions(-)
> 
> diff --git a/fs/cachefiles/io.c b/fs/cachefiles/io.c
> index 175a25fcade8..009d23cd435b 100644
> --- a/fs/cachefiles/io.c
> +++ b/fs/cachefiles/io.c
> @@ -259,9 +259,7 @@ static void cachefiles_write_complete(struct kiocb *iocb, long ret)
>  
>  	_enter("%ld", ret);
>  
> -	/* Tell lockdep we inherited freeze protection from submission thread */
> -	__sb_writers_acquired(inode->i_sb, SB_FREEZE_WRITE);
> -	__sb_end_write(inode->i_sb, SB_FREEZE_WRITE);
> +	kiocb_end_write(iocb);
>  
>  	if (ret < 0)
>  		trace_cachefiles_io_error(object, inode, ret,
> @@ -286,7 +284,6 @@ int __cachefiles_write(struct cachefiles_object *object,
>  {
>  	struct cachefiles_cache *cache;
>  	struct cachefiles_kiocb *ki;
> -	struct inode *inode;
>  	unsigned int old_nofs;
>  	ssize_t ret;
>  	size_t len = iov_iter_count(iter);
> @@ -322,19 +319,12 @@ int __cachefiles_write(struct cachefiles_object *object,
>  		ki->iocb.ki_complete = cachefiles_write_complete;
>  	atomic_long_add(ki->b_writing, &cache->b_writing);
>  
> -	/* Open-code file_start_write here to grab freeze protection, which
> -	 * will be released by another thread in aio_complete_rw().  Fool
> -	 * lockdep by telling it the lock got released so that it doesn't
> -	 * complain about the held lock when we return to userspace.
> -	 */
> -	inode = file_inode(file);
> -	__sb_start_write(inode->i_sb, SB_FREEZE_WRITE);
> -	__sb_writers_release(inode->i_sb, SB_FREEZE_WRITE);
> +	kiocb_start_write(&ki->iocb);
>  
>  	get_file(ki->iocb.ki_filp);
>  	cachefiles_grab_object(object, cachefiles_obj_get_ioreq);
>  
> -	trace_cachefiles_write(object, inode, ki->iocb.ki_pos, len);
> +	trace_cachefiles_write(object, file_inode(file), ki->iocb.ki_pos, len);
>  	old_nofs = memalloc_nofs_save();
>  	ret = cachefiles_inject_write_error();
>  	if (ret == 0)
> -- 
> 2.34.1
> 
-- 
Jan Kara <jack@suse.com>
SUSE Labs, CR