Re: [PATCH 1/6] f2fs: compress: fix to guarantee persisting compressed blocks by CP

[Jaegeuk Kim]

On 12/20, Chao Yu wrote:
> If data block in compressed cluster is not persisted with metadata
> during checkpoint, after SPOR, the data may be corrupted, let's
> guarantee to write compressed page by checkpoint.
> 
> Fixes: 4c8ff7095bef ("f2fs: support data compression")
> Signed-off-by: Chao Yu <chao@xxxxxxxxxx>
> ---
>  fs/f2fs/compress.c |  3 ++-
>  fs/f2fs/data.c     | 12 +++++++++---
>  fs/f2fs/f2fs.h     |  3 ++-
>  3 files changed, 13 insertions(+), 5 deletions(-)
> 
> diff --git a/fs/f2fs/compress.c b/fs/f2fs/compress.c
> index 5b076329e9bf..1122db8cc0b0 100644
> --- a/fs/f2fs/compress.c
> +++ b/fs/f2fs/compress.c
> @@ -1442,6 +1442,7 @@ void f2fs_compress_write_end_io(struct bio *bio, struct page *page)
>  	struct f2fs_sb_info *sbi = bio->bi_private;
>  	struct compress_io_ctx *cic =
>  			(struct compress_io_ctx *)page_private(page);
> +	enum count_type type = WB_DATA_TYPE(page);
>  	int i;
>  
>  	if (unlikely(bio->bi_status))
> @@ -1449,7 +1450,7 @@ void f2fs_compress_write_end_io(struct bio *bio, struct page *page)
>  
>  	f2fs_compress_free_page(page);
>  
> -	dec_page_count(sbi, F2FS_WB_DATA);
> +	dec_page_count(sbi, type);
>  
>  	if (atomic_dec_return(&cic->pending_pages))
>  		return;
> diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
> index d28c97282e68..6c72a6e86ba8 100644
> --- a/fs/f2fs/data.c
> +++ b/fs/f2fs/data.c
> @@ -48,7 +48,7 @@ void f2fs_destroy_bioset(void)
>  	bioset_exit(&f2fs_bioset);
>  }
>  
> -static bool __is_cp_guaranteed(struct page *page)
> +bool f2fs_is_cp_guaranteed(struct page *page)
>  {
>  	struct address_space *mapping = page->mapping;
>  	struct inode *inode;
> @@ -66,7 +66,7 @@ static bool __is_cp_guaranteed(struct page *page)
>  		return true;
>  
>  	if (f2fs_is_compressed_page(page))
> -		return false;
> +		return true;
>  	if ((S_ISREG(inode->i_mode) && IS_NOQUOTA(inode)) ||
>  			page_private_gcing(page))
>  		return true;
> @@ -1007,6 +1007,7 @@ void f2fs_submit_page_write(struct f2fs_io_info *fio)
>  	enum page_type btype = PAGE_TYPE_OF_BIO(fio->type);
>  	struct f2fs_bio_info *io = sbi->write_io[btype] + fio->temp;
>  	struct page *bio_page;
> +	enum count_type type;
>  
>  	f2fs_bug_on(sbi, is_read_io(fio->op));
>  
> @@ -1046,7 +1047,12 @@ void f2fs_submit_page_write(struct f2fs_io_info *fio)
>  	/* set submitted = true as a return value */
>  	fio->submitted = 1;
>  
> -	inc_page_count(sbi, WB_DATA_TYPE(bio_page));
> +	type = WB_DATA_TYPE(bio_page);
> +	/* override count type if page is compressed one */
> +	if (fio->compressed_page)
> +		type = WB_DATA_TYPE(fio->compressed_page);

Doesn't bio_page already point fio->compressed_page?

> +
> +	inc_page_count(sbi, type);
>  
>  	if (io->bio &&
>  	    (!io_is_mergeable(sbi, io->bio, io, fio, io->last_block_in_bio,
> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
> index 76e9a8682e38..bcb3940ab5ba 100644
> --- a/fs/f2fs/f2fs.h
> +++ b/fs/f2fs/f2fs.h
> @@ -1092,7 +1092,7 @@ struct f2fs_sm_info {
>   * f2fs monitors the number of several block types such as on-writeback,
>   * dirty dentry blocks, dirty node blocks, and dirty meta blocks.
>   */
> -#define WB_DATA_TYPE(p)	(__is_cp_guaranteed(p) ? F2FS_WB_CP_DATA : F2FS_WB_DATA)
> +#define WB_DATA_TYPE(p)	(f2fs_is_cp_guaranteed(p) ? F2FS_WB_CP_DATA : F2FS_WB_DATA)
>  enum count_type {
>  	F2FS_DIRTY_DENTS,
>  	F2FS_DIRTY_DATA,
> @@ -3824,6 +3824,7 @@ void f2fs_init_ckpt_req_control(struct f2fs_sb_info *sbi);
>   */
>  int __init f2fs_init_bioset(void);
>  void f2fs_destroy_bioset(void);
> +bool f2fs_is_cp_guaranteed(struct page *page);
>  int f2fs_init_bio_entry_cache(void);
>  void f2fs_destroy_bio_entry_cache(void);
>  void f2fs_submit_read_bio(struct f2fs_sb_info *sbi, struct bio *bio,
> -- 
> 2.40.1