[PATCH v3 3/4] f2fs: atomic: fix to truncate pagecache before on-disk metadata truncation

[Chao Yu]

We should always truncate pagecache while truncating on-disk data.

Fixes: a46bebd502fe ("f2fs: synchronize atomic write aborts")
Signed-off-by: Chao Yu <chao@xxxxxxxxxx>
---
v3:
- check dirty page before truncation
- use invalidate_mapping_pages() instead of truncate_inode_pages()
- set i_size to zero after truncation
 fs/f2fs/file.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index ac61c88f7688..a316c21539d1 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -2199,11 +2199,17 @@ static int f2fs_ioc_start_atomic_write(struct file *filp, bool truncate)
 		F2FS_I(fi->cow_inode)->atomic_inode = inode;
 	} else {
 		/* Reuse the already created COW inode */
+		f2fs_bug_on(sbi, get_dirty_pages(fi->cow_inode));
+
+		invalidate_mapping_pages(fi->cow_inode->i_mapping, 0, -1);
+
 		ret = f2fs_do_truncate_blocks(fi->cow_inode, 0, true);
 		if (ret) {
 			f2fs_up_write(&fi->i_gc_rwsem[WRITE]);
 			goto out;
 		}
+
+		i_size_write(fi->cow_inode, 0);
 	}
 
 	f2fs_write_inode(inode, NULL);
-- 
2.40.1