Linux: syncfs(2) should sync all cached files

While debugging problem with data not being synced on umount, we've noticed that even syncfs(2) doesn't help to get the data written out. It is because it doesn't actually sync any of the live znodes. Signed-off-by: Pavel Snajdr <[email protected]>
openzfs · Nov 29, 2024 · 88d1c8e · 88d1c8e
1 parent 0ffa6f3
commit 88d1c8e
Showing 1 changed file with 13 additions and 1 deletion.
diff --git a/module/os/linux/zfs/zpl_super.c b/module/os/linux/zfs/zpl_super.c
@@ -109,11 +109,23 @@ zpl_sync_fs(struct super_block *sb, int wait)
 {
 	fstrans_cookie_t cookie;
 	cred_t *cr = CRED();
+	znode_t *zp;
+	zfsvfs_t *zfsvfs = sb->s_fs_info;
 	int error;
 
 	crhold(cr);
 	cookie = spl_fstrans_mark();
-	error = -zfs_sync(sb, wait, cr);
+	mutex_enter(&zfsvfs->z_znodes_lock);
+	for (zp = list_head(&zfsvfs->z_all_znodes); zp;
+	    zp = list_next(&zfsvfs->z_all_znodes, zp)) {
+		if (zp->z_sa_hdl)
+			error = zpl_fsync(zp, 0, LLONG_MAX, wait);
+		if (error != 0)
+			break;
+	}
+	mutex_exit(&zfsvfs->z_znodes_lock);
+	if (error == 0)
+		error = -zfs_sync(sb, wait, cr);
 	spl_fstrans_unmark(cookie);
 	crfree(cr);
 	ASSERT3S(error, <=, 0);