Implement overlayfs' ->writepages operation so that
we can sync dirty data/metadata to upper filesystem.
Signed-off-by: Chengguang Xu <cgxu519@xxxxxxxxxxxx>
---
fs/overlayfs/inode.c | 13 +++++++++++++
1 file changed, 13 insertions(+)
diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c
index 832b17589733..d854e59a3710 100644
--- a/fs/overlayfs/inode.c
+++ b/fs/overlayfs/inode.c
@@ -659,9 +659,22 @@ static const struct inode_operations ovl_special_inode_operations = {
.update_time = ovl_update_time,
};
+static int ovl_writepages(struct address_space *mapping,
+ struct writeback_control *wbc)
+{
+ struct inode *inode = mapping->host;
+ struct ovl_fs *ofs = inode->i_sb->s_fs_info;
+ struct inode *upper = ovl_inode_upper(inode);
+
+ if (!ovl_should_sync(ofs))
+ return 0;
+ return filemap_fdatawrite_wbc(upper->i_mapping, wbc);
+}
+
static const struct address_space_operations ovl_aops = {
/* For O_DIRECT dentry_open() checks f_mapping->a_ops->direct_IO */
.direct_IO = noop_direct_IO,
+ .writepages = ovl_writepages,
};
/*
--
2.27.0
