fs/ntfs3: fsync files by syncing parent inodes

Some xfstests expect fsync() on a file or directory to also persist
directory metadata up the parent chain. Using generic_file_fsync() is not
sufficient for ntfs, because parent directories are not explicitly
written out.

Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>

Author: aalexandrovich

fs/ntfs3/dir.c

@@ -668,7 +668,7 @@ const struct file_operations ntfs_dir_operations = {
 	.llseek		= generic_file_llseek,
 	.read		= generic_read_dir,
 	.iterate_shared	= ntfs_readdir,
-	.fsync		= generic_file_fsync,
+	.fsync		= ntfs_file_fsync,
 	.open		= ntfs_file_open,
 	.unlocked_ioctl = ntfs_ioctl,
 #ifdef CONFIG_COMPAT

fs/ntfs3/file.c

@@ -1443,13 +1443,37 @@ static ssize_t ntfs_file_splice_write(struct pipe_inode_info *pipe,
 /*
  * ntfs_file_fsync - file_operations::fsync
  */
-static int ntfs_file_fsync(struct file *file, loff_t start, loff_t end, int datasync)
+int ntfs_file_fsync(struct file *file, loff_t start, loff_t end, int datasync)
 {
 	struct inode *inode = file_inode(file);
-	if (unlikely(ntfs3_forced_shutdown(inode->i_sb)))
+	struct super_block *sb = inode->i_sb;
+	struct ntfs_sb_info *sbi = sb->s_fs_info;
+	int err, ret;
+
+	if (unlikely(ntfs3_forced_shutdown(sb)))
 		return -EIO;
 
-	return generic_file_fsync(file, start, end, datasync);
+	ret = file_write_and_wait_range(file, start, end);
+	if (ret)
+		return ret;
+
+	ret = write_inode_now(inode, !datasync);
+
+	if (!ret) {
+		ret = ni_write_parents(ntfs_i(inode), !datasync);
+	}
+
+	if (!ret) {
+		ntfs_set_state(sbi, NTFS_DIRTY_CLEAR);
+		ntfs_update_mftmirr(sbi, false);
+	}
+
+	err = sync_blockdev(sb->s_bdev);
+	if (unlikely(err && !ret))
+		ret = err;
+	if (!ret)
+		blkdev_issue_flush(sb->s_bdev);
+	return ret;
 }
 
 // clang-format off

fs/ntfs3/frecord.c

@@ -3001,6 +3001,57 @@ bool ni_is_dirty(struct inode *inode)
 	return false;
 }
 
+/*
+ * ni_write_parents
+ *
+ * Helper function for ntfs_file_fsync.
+ */
+int ni_write_parents(struct ntfs_inode *ni, int sync)
+{
+	int err = 0;
+	struct ATTRIB *attr = NULL;
+	struct ATTR_LIST_ENTRY *le = NULL;
+	struct ntfs_sb_info *sbi = ni->mi.sbi;
+	struct super_block *sb = sbi->sb;
+
+	while ((attr = ni_find_attr(ni, attr, &le, ATTR_NAME, NULL, 0, NULL,
+				    NULL))) {
+		struct inode *dir;
+		struct ATTR_FILE_NAME *fname;
+
+		fname = resident_data_ex(attr, SIZEOF_ATTRIBUTE_FILENAME);
+		if (!fname)
+			continue;
+
+		/* Check simple case when parent inode equals current inode. */
+		if (ino_get(&fname->home) == ni->vfs_inode.i_ino) {
+			if (MFT_REC_ROOT != ni->vfs_inode.i_ino) {
+				ntfs_set_state(sbi, NTFS_DIRTY_ERROR);
+				err = -EINVAL;
+			}
+			continue;
+		}
+
+		dir = ntfs_iget5(sb, &fname->home, NULL);
+		if (IS_ERR(dir)) {
+			ntfs_inode_warn(
+				&ni->vfs_inode,
+				"failed to open parent directory r=%lx to write",
+				(long)ino_get(&fname->home));
+			continue;
+		}
+
+		if (!is_bad_inode(dir)) {
+			int err2 = write_inode_now(dir, sync);
+			if (!err)
+				err = err2;
+		}
+		iput(dir);
+	}
+
+	return err;
+}
+
 /*
  * ni_update_parent
  *

fs/ntfs3/ntfs_fs.h

@@ -512,6 +512,7 @@ int ntfs_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
 int ntfs_file_open(struct inode *inode, struct file *file);
 int ntfs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
 		__u64 start, __u64 len);
+int ntfs_file_fsync(struct file *file, loff_t start, loff_t end, int datasync);
 long ntfs_ioctl(struct file *filp, u32 cmd, unsigned long arg);
 long ntfs_compat_ioctl(struct file *filp, u32 cmd, unsigned long arg);
 extern const struct inode_operations ntfs_special_inode_operations;
@@ -590,6 +591,7 @@ int ni_rename(struct ntfs_inode *dir_ni, struct ntfs_inode *new_dir_ni,
 	      struct NTFS_DE *new_de);
 
 bool ni_is_dirty(struct inode *inode);
+int ni_write_parents(struct ntfs_inode *ni, int sync);
 
 /* Globals from fslog.c */
 bool check_index_header(const struct INDEX_HDR *hdr, size_t bytes);