Re: [PATCH 1/6] fs: remove an outdated comment on mpage_writepages

Jan Kara
2023-01-02T12:13:32Z

On Thu 29-12-22 06:10:26, Christoph Hellwig wrote:
> mpage_writepages doesn't do any of the page locking itself, so remove
> and outdated comment on the locking pattern there.
>
> Signed-off-by: Christoph Hellwig <hch@lst.de>

Looks good. Feel free to add:

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

Honza

> ---
> fs/mpage.c | 8 --------
> 1 file changed, 8 deletions(-)
>
> diff --git a/fs/mpage.c b/fs/mpage.c
> index 0f8ae954a57903..910cfe8a60d2e4 100644
> --- a/fs/mpage.c
> +++ b/fs/mpage.c
> @@ -641,14 +641,6 @@ static int __mpage_writepage(struct page *page, struct writeback_control *wbc,
> *
> * This is a library function, which implements the writepages()
> * address_space_operation.
> - *
> - * If a page is already under I/O, generic_writepages() skips it, even
> - * if it's dirty. This is desirable behaviour for memory-cleaning writeback,
> - * but it is INCORRECT for data-integrity system calls such as fsync(). fsync()
> - * and msync() need to guarantee that all the data which was dirty at the time
> - * the call was made get new I/O started against them. If wbc->sync_mode is
> - * WB_SYNC_ALL then we were called for data integrity and we must wait for
> - * existing IO to complete.
> */
> int
> mpage_writepages(struct address_space *mapping,
> --
> 2.35.1
>
--
Jan Kara <jack@suse.com>
SUSE Labs, CR