3233,19 @@ static inline bool __should_serialize_io(struct inode *inode,
 	return false;
 }
 
+static inline void account_writeback(struct inode *inode, bool inc)
+{
+	if (!f2fs_sb_has_compression(F2FS_I_SB(inode)))
+		return;
+
+	f2fs_down_read(&F2FS_I(inode)->i_sem);
+	if (inc)
+		atomic_inc(&F2FS_I(inode)->writeback);
+	else
+		atomic_dec(&F2FS_I(inode)->writeback);
+	f2fs_up_read(&F2FS_I(inode)->i_sem);
+}
+
 static int __f2fs_write_data_pages(struct address_space *mapping,
 						struct writeback_control *wbc,
 						enum iostat_type io_type)
@@ -3282,10 +3295,14 @@ static int __f2fs_write_data_pages(struct address_space *mapping,
 		locked = true;
 	}
 
+	account_writeback(inode, true);
+
 	blk_start_plug(&plug);
 	ret = f2fs_write_cache_pages(mapping, wbc, io_type);
 	blk_finish_plug(&plug);
 
+	account_writeback(inode, false);
+
 	if (locked)
 		mutex_unlock(&sbi->writepages);
 
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 4b295671df8b..b45f7ce568e6 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -863,6 +863,7 @@ struct f2fs_inode_info {
 	unsigned char i_compress_level;		/* compress level (lz4hc,zstd) */
 	unsigned char i_compress_flag;		/* compress flag */
 	unsigned int i_cluster_size;		/* cluster size */
+	atomic_t writeback;			/* count # of writeback thread */
 
 	unsigned int atomic_write_cnt;
 	loff_t original_i_size;		/* original i_size before atomic write */
@@ -4480,7 +4481,7 @@ static inline bool f2fs_disable_compressed_file(struct inode *inode)
 		f2fs_up_write(&F2FS_I(inode)->i_sem);
 		return true;
 	}
-	if (f2fs_is_mmap_file(inode) ||
+	if (f2fs_is_mmap_file(inode) || atomic_read(&fi->writeback) ||
 		(S_ISREG(inode->i_mode) && F2FS_HAS_BLOCKS(inode))) {
 		f2fs_up_write(&F2FS_I(inode)->i_sem);
 		return false;
diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index 7bdf0da5ba69..8cc0b7f5c35d 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -2042,8 +2042,9 @@ static int f2fs_setflags_common(struct inode *inode, u32 iflags, u32 mask)
 
 			f2fs_down_write(&F2FS_I(inode)->i_sem);
 			if (!f2fs_may_compress(inode) ||
-					(S_ISREG(inode->i_mode) &&
-					F2FS_HAS_BLOCKS(inode))) {
+				atomic_read(&fi->writeback) ||
+				(S_ISREG(inode->i_mode) &&
+				F2FS_HAS_BLOCKS(inode))) {
 				f2fs_up_write(&F2FS_I(inode)->i_sem);
 				return -EINVAL;
 			}
diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index 0523e21fa951..30b57755ceef 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -1410,6 +1410,7 @@ static struct inode *f2fs_alloc_inode(struct super_block *sb)
 	atomic_set(&fi->dirty_pages, 0);
 	atomic_set(&fi->i_compr_blocks, 0);
 	atomic_set(&fi->open_count, 0);
+	atomic_set(&fi->writeback, 0);
 	init_f2fs_rwsem(&fi->i_sem);
 	spin_lock_init(&fi->i_size_lock);
 	INIT_LIST_HEAD(&fi->dirty_list);
-- 
2.51.0[PATCH 6.6.y 4/4] f2fs: fix to avoid updating compression context during writebackSasha Levin <sashal@kernel.org> undefinedstable@vger.kernel.org undefined undefined undefined undefined undefined”„ĺC