On Thu 27-05-21 21:56:40, Zhang Yi wrote:
> After we introduce a jbd2 shrinker to release checkpointed buffer's
> journal head, we could free buffer without bdev_try_to_free_page()
> under memory pressure. So this patch remove the whole
> bdev_try_to_free_page() callback directly. It also remove many
> use-after-free issues relate to it together.
>
> Signed-off-by: Zhang Yi <yi.zhang@xxxxxxxxxx>
Looks good. Feel free to add:
Reviewed-by: Jan Kara <jack@xxxxxxx>
Honza
> ---
> fs/ext4/super.c | 21 ---------------------
> 1 file changed, 21 deletions(-)
>
> diff --git a/fs/ext4/super.c b/fs/ext4/super.c
> index bf6d0085e1b7..b778236d06e6 100644
> --- a/fs/ext4/super.c
> +++ b/fs/ext4/super.c
> @@ -1442,26 +1442,6 @@ static int ext4_nfs_commit_metadata(struct inode *inode)
> return ext4_write_inode(inode, &wbc);
> }
>
> -/*
> - * Try to release metadata pages (indirect blocks, directories) which are
> - * mapped via the block device. Since these pages could have journal heads
> - * which would prevent try_to_free_buffers() from freeing them, we must use
> - * jbd2 layer's try_to_free_buffers() function to release them.
> - */
> -static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
> - gfp_t wait)
> -{
> - journal_t *journal = EXT4_SB(sb)->s_journal;
> -
> - WARN_ON(PageChecked(page));
> - if (!page_has_buffers(page))
> - return 0;
> - if (journal)
> - return jbd2_journal_try_to_free_buffers(journal, page);
> -
> - return try_to_free_buffers(page);
> -}
> -
> #ifdef CONFIG_FS_ENCRYPTION
> static int ext4_get_context(struct inode *inode, void *ctx, size_t len)
> {
> @@ -1656,7 +1636,6 @@ static const struct super_operations ext4_sops = {
> .quota_write = ext4_quota_write,
> .get_dquots = ext4_get_dquots,
> #endif
> - .bdev_try_to_free_page = bdev_try_to_free_page,
> };
>
> static const struct export_operations ext4_export_ops = {
> --
> 2.25.4
>
--
Jan Kara <jack@xxxxxxxx>
SUSE Labs, CR
