files: Add fdinfo_list_entry::stage

Add fle open stages. Set a stage after every operation.

v2: Do not merge filetype specific state with generic.

travis-ci: success for Rework file opening scheme to make it asynchronous (rev5)
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

criu/files.c

@@ -1005,12 +1005,16 @@ static int post_open_fd(int pid, struct fdinfo_list_entry *fle)
 			return -1;
 		}
 		if (!is_service_fd(fle->fe->fd, CTL_TTY_OFF))
-			return 0;
+			goto out;
 	}
 
 	if (!d->ops->post_open)
-		return 0;
-	return d->ops->post_open(d, fle->fe->fd);
+		goto out;
+	if (d->ops->post_open(d, fle->fe->fd))
+		return -1;
+out:
+	fle->stage = FLE_RESTORED;
+	return 0;
 }
 
 
@@ -1058,6 +1062,8 @@ static int open_fd(int pid, struct fdinfo_list_entry *fle)
 		return -1;
 	}
 
+	fle->stage = FLE_OPEN;
+
 	return serve_out_fd(pid, fle->fe->fd, d);
 }
 

criu/include/files.h

@@ -64,6 +64,12 @@ extern int fill_fdlink(int lfd, const struct fd_parms *p, struct fd_link *link);
 
 struct file_desc;
 
+enum {
+	FLE_INITIALIZED,
+	FLE_OPEN,
+	FLE_RESTORED,
+};
+
 struct fdinfo_list_entry {
 	struct list_head	desc_list;	/* To chain on  @fd_info_head */
 	struct file_desc	*desc;		/* Associated file descriptor */
@@ -72,6 +78,7 @@ struct fdinfo_list_entry {
 	int			pid;
 	FdinfoEntry		*fe;
 	u8			received:1;
+	u8			stage:3;
 };
 
 static inline void fle_init(struct fdinfo_list_entry *fle, int pid, FdinfoEntry *fe)
@@ -79,6 +86,7 @@ static inline void fle_init(struct fdinfo_list_entry *fle, int pid, FdinfoEntry
 	fle->pid = pid;
 	fle->fe = fe;
 	fle->received = 0;
+	fle->stage = FLE_INITIALIZED;
 }
 
 /* reports whether fd_a takes prio over fd_b */