Re: [PATCHv2 3/3] reiser4: mark pages created during tail2extent conversion as dirty.

[Edward Shishkin <edward.shishkin@gmail.com>]

On 10/25/2015 01:02 AM, Ivan Shapovalov wrote:
> This is responsible for an oops in v4.2 in
> write_jnodes_to_disk_extent() -> set_page_writeback().
>
> The pages needs to be marked dirty before marked writeback.
>
>  From a similar problem in f2fs:
> "The cgroup attaches inode->i_wb via mark_inode_dirty and when
> set_page_writeback is called, __inc_wb_stat() updates i_wb's stat.
>
> So, we need to explicitly call set_page_dirty->__mark_inode_dirty in
> prior to any writebacking pages."
>
> Signed-off-by: Ivan Shapovalov <intelfx100@gmail.com>
> ---
>   fs/reiser4/plugin/file/tail_conversion.c | 1 +
>   1 file changed, 1 insertion(+)
>
> diff --git a/fs/reiser4/plugin/file/tail_conversion.c b/fs/reiser4/plugin/file/tail_conversion.c
> index 7542c03..c856b73 100644
> --- a/fs/reiser4/plugin/file/tail_conversion.c
> +++ b/fs/reiser4/plugin/file/tail_conversion.c
> @@ -175,6 +175,7 @@ static int replace(struct inode *inode, struct page **pages, unsigned nr_pages,
>   								i_mapping));
>   		if (result)
>   			break;
> +		set_page_dirty_notag(pages[i]);


So, at this point the page is dirty but not uptodate.
I am confused with this. Why not to set the page
uptodate right before setting it dirty? At this point
everything has been copied already, so the page is
in fact uptodate. Could you please try this?

Thanks,
Edward.


>   		unlock_page(pages[i]);
>   		result = find_or_create_extent(pages[i]);
>   		if (result) {