f2fs: compress: fix to guarantee persisting compressed blocks by CP

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: 4c8ff709 ("f2fs: support data compression")
Reviewed-by: Daeho Jeong <daehojeong@google.com>
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

fs/f2fs/compress.c

@@ -1418,6 +1418,8 @@ 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,
+				f2fs_is_compressed_page(page));
 	int i;
 
 	if (unlikely(bio->bi_status))
@@ -1425,7 +1427,7 @@ 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;

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;
@@ -65,8 +65,6 @@ static bool __is_cp_guaranteed(struct page *page)
 			S_ISDIR(inode->i_mode))
 		return true;
 
-	if (f2fs_is_compressed_page(page))
-		return false;
 	if ((S_ISREG(inode->i_mode) && IS_NOQUOTA(inode)) ||
 			page_private_gcing(page))
 		return true;
@@ -338,7 +336,7 @@ static void f2fs_write_end_io(struct bio *bio)
 
 	bio_for_each_segment_all(bvec, bio, iter_all) {
 		struct page *page = bvec->bv_page;
-		enum count_type type = WB_DATA_TYPE(page);
+		enum count_type type = WB_DATA_TYPE(page, false);
 
 		if (page_private_dummy(page)) {
 			clear_page_private_dummy(page);
@@ -762,7 +760,7 @@ int f2fs_submit_page_bio(struct f2fs_io_info *fio)
 		wbc_account_cgroup_owner(fio->io_wbc, fio->page, PAGE_SIZE);
 
 	inc_page_count(fio->sbi, is_read_io(fio->op) ?
-			__read_io_type(page) : WB_DATA_TYPE(fio->page));
+			__read_io_type(page) : WB_DATA_TYPE(fio->page, false));
 
 	if (is_read_io(bio_op(bio)))
 		f2fs_submit_read_bio(fio->sbi, bio, fio->type);
@@ -973,7 +971,7 @@ int f2fs_merge_page_bio(struct f2fs_io_info *fio)
 	if (fio->io_wbc)
 		wbc_account_cgroup_owner(fio->io_wbc, fio->page, PAGE_SIZE);
 
-	inc_page_count(fio->sbi, WB_DATA_TYPE(page));
+	inc_page_count(fio->sbi, WB_DATA_TYPE(page, false));
 
 	*fio->last_block = fio->new_blkaddr;
 	*fio->bio = bio;
@@ -1007,6 +1005,7 @@ 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 +1045,8 @@ 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, fio->compressed_page);
+	inc_page_count(sbi, type);
 
 	if (io->bio &&
 	    (!io_is_mergeable(sbi, io->bio, io, fio, io->last_block_in_bio,
@@ -1059,7 +1059,8 @@ void f2fs_submit_page_write(struct f2fs_io_info *fio)
 		if (F2FS_IO_ALIGNED(sbi) &&
 				(fio->type == DATA || fio->type == NODE) &&
 				fio->new_blkaddr & F2FS_IO_SIZE_MASK(sbi)) {
-			dec_page_count(sbi, WB_DATA_TYPE(bio_page));
+			dec_page_count(sbi, WB_DATA_TYPE(bio_page,
+						fio->compressed_page));
 			fio->retry = 1;
 			goto skip;
 		}

fs/f2fs/f2fs.h

@@ -1080,7 +1080,8 @@ 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, f)			\
+	(f || f2fs_is_cp_guaranteed(p) ? F2FS_WB_CP_DATA : F2FS_WB_DATA)
 enum count_type {
 	F2FS_DIRTY_DENTS,
 	F2FS_DIRTY_DATA,
@@ -3804,6 +3805,7 @@ 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,