[CRIU] [PATCH 3/4] soccr: Move queue pointers from _data

[Pavel Emelyanov]

Signed-off-by: Pavel Emelyanov <xemul at virtuozzo.com>
---
 criu/sk-tcp.c |  9 +--------
 soccr/soccr.c | 46 ++++++++++++++++++++++++++++++++++++++++------
 soccr/soccr.h | 12 +++++++++---
 3 files changed, 50 insertions(+), 17 deletions(-)

diff --git a/criu/sk-tcp.c b/criu/sk-tcp.c
index f7eef52..bfc5cb9 100644
--- a/criu/sk-tcp.c
+++ b/criu/sk-tcp.c
@@ -257,12 +257,7 @@ static int read_tcp_queue(struct libsoccr_sk *sk, struct libsoccr_sk_data *data,
 	if (read_img_buf(img, buf, len) < 0)
 		goto err;
 
-	if (queue == TCP_SEND_QUEUE)
-		data->outq_data = buf;
-	else
-		data->inq_data = buf;
-
-	return 0;
+	return libsoccr_set_queue_bytes(sk, queue, buf, SOCCR_MEM_EXCL);
 
 err:
 	xfree(buf);
@@ -379,8 +374,6 @@ static int restore_tcp_conn_state(int sk, struct libsoccr_sk *socr, struct inet_
 	return 0;
 
 err_c:
-	xfree(data.inq_data);
-	xfree(data.outq_data);
 	tcp_stream_entry__free_unpacked(tse, NULL);
 	close_image(img);
 err:
diff --git a/soccr/soccr.c b/soccr/soccr.c
index d0c8668..11ac28c 100644
--- a/soccr/soccr.c
+++ b/soccr/soccr.c
@@ -104,10 +104,14 @@ static int tcp_repair_off(int fd)
 
 struct libsoccr_sk {
 	int fd;
+	unsigned flags;
 	char *recv_queue;
 	char *send_queue;
 };
 
+#define SK_FLAG_FREE_RQ		0x1
+#define SK_FLAG_FREE_SQ		0x2
+
 struct libsoccr_sk *libsoccr_pause(int fd)
 {
 	struct libsoccr_sk *ret;
@@ -121,6 +125,7 @@ struct libsoccr_sk *libsoccr_pause(int fd)
 		return NULL;
 	}
 
+	ret->flags = 0;
 	ret->recv_queue = NULL;
 	ret->send_queue = NULL;
 	ret->fd = fd;
@@ -130,8 +135,10 @@ struct libsoccr_sk *libsoccr_pause(int fd)
 void libsoccr_resume(struct libsoccr_sk *sk)
 {
 	tcp_repair_off(sk->fd);
-	free(sk->send_queue);
-	free(sk->recv_queue);
+	if (sk->flags & SK_FLAG_FREE_RQ)
+		free(sk->recv_queue);
+	if (sk->flags & SK_FLAG_FREE_SQ)
+		free(sk->send_queue);
 	free(sk);
 }
 
@@ -345,6 +352,8 @@ int libsoccr_save(struct libsoccr_sk *sk, struct libsoccr_sk_data *data, unsigne
 	if (get_window(sk, data))
 		return -4;
 
+	sk->flags |= SK_FLAG_FREE_SQ | SK_FLAG_FREE_RQ;
+
 	if (get_queue(sk->fd, TCP_RECV_QUEUE, &data->inq_seq, data->inq_len, &sk->recv_queue))
 		return -4;
 
@@ -623,7 +632,7 @@ static int restore_fin_in_snd_queue(int sk, int acked)
 	return ret;
 }
 
-static int libsoccr_set_queue_bytes(struct libsoccr_sk *sk, struct libsoccr_sk_data *data, unsigned data_size,
+static int libsoccr_restore_queue(struct libsoccr_sk *sk, struct libsoccr_sk_data *data, unsigned data_size,
 		int queue, char *buf);
 
 int libsoccr_restore(struct libsoccr_sk *sk,
@@ -634,10 +643,10 @@ int libsoccr_restore(struct libsoccr_sk *sk,
 	if (libsoccr_set_sk_data_noq(sk, data, data_size))
 		return -1;
 
-	if (libsoccr_set_queue_bytes(sk, data, sizeof(*data), TCP_RECV_QUEUE, data->inq_data))
+	if (libsoccr_restore_queue(sk, data, sizeof(*data), TCP_RECV_QUEUE, sk->recv_queue))
 		return -1;
 
-	if (libsoccr_set_queue_bytes(sk, data, sizeof(*data), TCP_SEND_QUEUE, data->outq_data))
+	if (libsoccr_restore_queue(sk, data, sizeof(*data), TCP_SEND_QUEUE, sk->send_queue))
 		return -1;
 
 	if (data->flags & SOCCR_FLAGS_WINDOW) {
@@ -749,9 +758,12 @@ static int send_queue(struct libsoccr_sk *sk, int queue, char *buf, __u32 len)
 	return __send_queue(sk, queue, buf, len);
 }
 
-static int libsoccr_set_queue_bytes(struct libsoccr_sk *sk, struct libsoccr_sk_data *data, unsigned data_size,
+static int libsoccr_restore_queue(struct libsoccr_sk *sk, struct libsoccr_sk_data *data, unsigned data_size,
 		int queue, char *buf)
 {
+	if (!buf)
+		return 0;
+
 	if (!data || data_size < SOCR_DATA_MIN_SIZE)
 		return -1;
 
@@ -793,3 +805,25 @@ static int libsoccr_set_queue_bytes(struct libsoccr_sk *sk, struct libsoccr_sk_d
 
 	return -5;
 }
+
+#define SET_Q_FLAGS	(SOCCR_MEM_EXCL)
+int libsoccr_set_queue_bytes(struct libsoccr_sk *sk, int queue_id, char *bytes, unsigned flags)
+{
+	if (flags & ~SET_Q_FLAGS)
+		return -1;
+
+	switch (queue_id) {
+		case TCP_RECV_QUEUE:
+			sk->recv_queue = bytes;
+			if (flags & SOCCR_MEM_EXCL)
+				sk->flags |= SK_FLAG_FREE_RQ;
+			break;
+		case TCP_SEND_QUEUE:
+			sk->send_queue = bytes;
+			if (flags & SOCCR_MEM_EXCL)
+				sk->flags |= SK_FLAG_FREE_SQ;
+			return 0;
+	}
+
+	return -1;
+}
diff --git a/soccr/soccr.h b/soccr/soccr.h
index 1e4bfb3..cd73271 100644
--- a/soccr/soccr.h
+++ b/soccr/soccr.h
@@ -91,9 +91,6 @@ struct libsoccr_sk_data {
 	__u32	rcv_wnd;
 	__u32	rcv_wup;
 
-	char *inq_data;
-	char *outq_data;
-
 	union libsoccr_addr src_addr;
 	union libsoccr_addr dst_addr;
 };
@@ -196,6 +193,8 @@ char *libsoccr_get_queue_bytes(struct libsoccr_sk *sk, int queue_id, unsigned fl
  * 	sk = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP);
  *
  * 	h = libsoccr_pause(sk)
+ * 	libsoccr_set_queue_bytes(h, TCP_SEND_QUEUE, outq);
+ * 	libsoccr_set_queue_bytes(h, TCP_RECV_QUEUE, inq);
  * 	libsoccr_restore(h, &data, sizeof(data))
  *
  * 	libsoccr_resume(h)
@@ -205,6 +204,13 @@ char *libsoccr_get_queue_bytes(struct libsoccr_sk *sk, int queue_id, unsigned fl
  */
 
 /*
+ * Set a pointer on the send/recv queue data.
+ * If flags have SOCCR_MEM_EXCL, the buffer is stolen by the library and is 
+ * free()-ed after libsoccr_resume().
+ */
+int libsoccr_set_queue_bytes(struct libsoccr_sk *sk, int queue_id, char *bytes, unsigned flags);
+
+/*
  * Performs restore actions on bind()-ed socket
  */
 int libsoccr_restore(struct libsoccr_sk *sk, struct libsoccr_sk_data *data, unsigned data_size);
-- 
2.5.0