caif: Don't resend if dev_queue_xmit fails.

If CAIF Link Layer returns an error, we no longer try to re-build the CAIF packet and resend it. Instead, we simply return any transmission errors to the socket client. Signed-off-by: Sjur Brændeland <sjur.brandeland@stericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>

caif: Don't resend if dev_queue_xmit fails.
If CAIF Link Layer returns an error, we no longer try to re-build the CAIF packet and resend it. Instead, we simply return any transmission errors to the socket client. Signed-off-by: Sjur Brændeland <sjur.brandeland@stericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Sjur Brændeland · David S. Miller
1 parent 73d6ac633c
Showing 9 changed files with 14 additions and 88 deletions Side-by-side Diff
net/caif/caif_dev.c
net/caif/caif_socket.c
net/caif/cfdgml.c
net/caif/cffrml.c
net/caif/cfmuxl.c
net/caif/cfserl.c
net/caif/cfutill.c
net/caif/cfveil.c
net/caif/cfvidl.c
@@ -120,25 +120,12 @@
 {
 	struct caif_device_entry *caifd =
 	    container_of(layer, struct caif_device_entry, layer);
-	struct sk_buff *skb, *skb2;
-	int ret = -EINVAL;
+	struct sk_buff *skb;
+
 	skb = cfpkt_tonative(pkt);
 	skb->dev = caifd->netdev;
-	/*
-	 * Don't allow SKB to be destroyed upon error, but signal resend
-	 * notification to clients. We can't rely on the return value as
-	 * congestion (NET_XMIT_CN) sometimes drops the packet, sometimes don't.
-	 */
-	if (netif_queue_stopped(caifd->netdev))
-		return -EAGAIN;
-	skb2 = skb_get(skb);
  
-	ret = dev_queue_xmit(skb2);
-
-	if (!ret)
-		kfree_skb(skb);
-	else
-		return -EAGAIN;
+	dev_queue_xmit(skb);
  
 	return 0;
 }
@@ -519,43 +519,14 @@
 			int noblock, long timeo)
 {
 	struct cfpkt *pkt;
-	int ret, loopcnt = 0;
  
 	pkt = cfpkt_fromnative(CAIF_DIR_OUT, skb);
 	memset(cfpkt_info(pkt), 0, sizeof(struct caif_payload_info));
-	do {
  
-		ret = -ETIMEDOUT;
+	if (cf_sk->layer.dn == NULL)
+		return -EINVAL;
  
-		/* Slight paranoia, probably not needed. */
-		if (unlikely(loopcnt++ > 1000)) {
-			pr_warn("transmit retries failed, error = %d\n", ret);
-			break;
-		}
-
-		if (cf_sk->layer.dn != NULL)
-			ret = cf_sk->layer.dn->transmit(cf_sk->layer.dn, pkt);
-		if (likely(ret >= 0))
-			break;
-		/* if transmit return -EAGAIN, then retry */
-		if (noblock && ret == -EAGAIN)
-			break;
-		timeo = caif_wait_for_flow_on(cf_sk, 0, timeo, &ret);
-		if (signal_pending(current)) {
-			ret = sock_intr_errno(timeo);
-			break;
-		}
-		if (ret)
-			break;
-		if (cf_sk->sk.sk_state != CAIF_CONNECTED ||
-			sock_flag(&cf_sk->sk, SOCK_DEAD) ||
-			(cf_sk->sk.sk_shutdown & RCV_SHUTDOWN)) {
-			ret = -EPIPE;
-			cf_sk->sk.sk_err = EPIPE;
-			break;
-		}
-	} while (ret == -EAGAIN);
-	return ret;
+	return cf_sk->layer.dn->transmit(cf_sk->layer.dn, pkt);
 }
  
 /* Copied from af_unix:unix_dgram_sendmsg, and adapted to CAIF */
@@ -108,11 +108,6 @@
 	 */
 	info->hdr_len = 4;
 	info->dev_info = &service->dev_info;
-	ret = layr->dn->transmit(layr->dn, pkt);
-	if (ret < 0) {
-		u32 tmp32;
-		cfpkt_extr_head(pkt, &tmp32, 4);
-	}
-	return ret;
+	return layr->dn->transmit(layr->dn, pkt);
 }
@@ -120,7 +120,6 @@
 	int tmp;
 	u16 chks;
 	u16 len;
-	int ret;
 	struct cffrml *this = container_obj(layr);
 	if (this->dofcs) {
 		chks = cfpkt_iterate(pkt, cffrml_checksum, 0xffff);
@@ -137,12 +136,7 @@
 		pr_err("Packet is erroneous!\n");
 		return -EPROTO;
 	}
-	ret = layr->dn->transmit(layr->dn, pkt);
-	if (ret < 0) {
-		/* Remove header on faulty packet. */
-		cfpkt_extr_head(pkt, &tmp, 2);
-	}
-	return ret;
+	return layr->dn->transmit(layr->dn, pkt);
 }
  
 static void cffrml_ctrlcmd(struct cflayer *layr, enum caif_ctrlcmd ctrl,
@@ -184,7 +184,6 @@
  
 static int cfmuxl_transmit(struct cflayer *layr, struct cfpkt *pkt)
 {
-	int ret;
 	struct cfmuxl *muxl = container_obj(layr);
 	u8 linkid;
 	struct cflayer *dn;
@@ -198,11 +197,7 @@
 	info->hdr_len += 1;
 	linkid = info->channel_id;
 	cfpkt_add_head(pkt, &linkid, 1);
-	ret = dn->transmit(dn, pkt);
-	/* Remove MUX protocol header upon error. */
-	if (ret < 0)
-		cfpkt_extr_head(pkt, &linkid, 1);
-	return ret;
+	return dn->transmit(dn, pkt);
 }
  
 static void cfmuxl_ctrlcmd(struct cflayer *layr, enum caif_ctrlcmd ctrl,
@@ -179,15 +179,10 @@
 static int cfserl_transmit(struct cflayer *layer, struct cfpkt *newpkt)
 {
 	struct cfserl *layr = container_obj(layer);
-	int ret;
 	u8 tmp8 = CFSERL_STX;
 	if (layr->usestx)
 		cfpkt_add_head(newpkt, &tmp8, 1);
-	ret = layer->dn->transmit(layer->dn, newpkt);
-	if (ret < 0)
-		cfpkt_extr_head(newpkt, &tmp8, 1);
-
-	return ret;
+	return layer->dn->transmit(layer->dn, newpkt);
 }
  
 static void cfserl_ctrlcmd(struct cflayer *layr, enum caif_ctrlcmd ctrl,
@@ -100,11 +100,6 @@
 	 */
 	info->hdr_len = 1;
 	info->dev_info = &service->dev_info;
-	ret = layr->dn->transmit(layr->dn, pkt);
-	if (ret < 0) {
-		u32 tmp32;
-		cfpkt_extr_head(pkt, &tmp32, 4);
-	}
-	return ret;
+	return layr->dn->transmit(layr->dn, pkt);
 }
@@ -96,9 +96,6 @@
 	info->channel_id = service->layer.id;
 	info->hdr_len = 1;
 	info->dev_info = &service->dev_info;
-	ret = layr->dn->transmit(layr->dn, pkt);
-	if (ret < 0)
-		cfpkt_extr_head(pkt, &tmp, 1);
-	return ret;
+	return layr->dn->transmit(layr->dn, pkt);
 }
@@ -60,9 +60,6 @@
 	info = cfpkt_info(pkt);
 	info->channel_id = service->layer.id;
 	info->dev_info = &service->dev_info;
-	ret = layr->dn->transmit(layr->dn, pkt);
-	if (ret < 0)
-		cfpkt_extr_head(pkt, &videoheader, 4);
-	return ret;
+	return layr->dn->transmit(layr->dn, pkt);
 }
...	...	@@ -120,25 +120,12 @@
120	120	{
121	121	struct caif_device_entry *caifd =
122	122	container_of(layer, struct caif_device_entry, layer);
123		- struct sk_buff skb, skb2;
124		- int ret = -EINVAL;
	123	+ struct sk_buff *skb;
	124	+
125	125	skb = cfpkt_tonative(pkt);
126	126	skb->dev = caifd->netdev;
127		- /*
128		- * Don't allow SKB to be destroyed upon error, but signal resend
129		- * notification to clients. We can't rely on the return value as
130		- * congestion (NET_XMIT_CN) sometimes drops the packet, sometimes don't.
131		- */
132		- if (netif_queue_stopped(caifd->netdev))
133		- return -EAGAIN;
134		- skb2 = skb_get(skb);
135	127
136		- ret = dev_queue_xmit(skb2);
137		-
138		- if (!ret)
139		- kfree_skb(skb);
140		- else
141		- return -EAGAIN;
	128	+ dev_queue_xmit(skb);
142	129
143	130	return 0;
144	131	}
...	...	@@ -519,43 +519,14 @@
519	519	int noblock, long timeo)
520	520	{
521	521	struct cfpkt *pkt;
522		- int ret, loopcnt = 0;
523	522
524	523	pkt = cfpkt_fromnative(CAIF_DIR_OUT, skb);
525	524	memset(cfpkt_info(pkt), 0, sizeof(struct caif_payload_info));
526		- do {
527	525
528		- ret = -ETIMEDOUT;
	526	+ if (cf_sk->layer.dn == NULL)
	527	+ return -EINVAL;
529	528
530		- /* Slight paranoia, probably not needed. */
531		- if (unlikely(loopcnt++ > 1000)) {
532		- pr_warn("transmit retries failed, error = %d\n", ret);
533		- break;
534		- }
535		-
536		- if (cf_sk->layer.dn != NULL)
537		- ret = cf_sk->layer.dn->transmit(cf_sk->layer.dn, pkt);
538		- if (likely(ret >= 0))
539		- break;
540		- /* if transmit return -EAGAIN, then retry */
541		- if (noblock && ret == -EAGAIN)
542		- break;
543		- timeo = caif_wait_for_flow_on(cf_sk, 0, timeo, &ret);
544		- if (signal_pending(current)) {
545		- ret = sock_intr_errno(timeo);
546		- break;
547		- }
548		- if (ret)
549		- break;
550		- if (cf_sk->sk.sk_state != CAIF_CONNECTED \|\|
551		- sock_flag(&cf_sk->sk, SOCK_DEAD) \|\|
552		- (cf_sk->sk.sk_shutdown & RCV_SHUTDOWN)) {
553		- ret = -EPIPE;
554		- cf_sk->sk.sk_err = EPIPE;
555		- break;
556		- }
557		- } while (ret == -EAGAIN);
558		- return ret;
	529	+ return cf_sk->layer.dn->transmit(cf_sk->layer.dn, pkt);
559	530	}
560	531
561	532	/* Copied from af_unix:unix_dgram_sendmsg, and adapted to CAIF */
...	...	@@ -108,11 +108,6 @@
108	108	*/
109	109	info->hdr_len = 4;
110	110	info->dev_info = &service->dev_info;
111		- ret = layr->dn->transmit(layr->dn, pkt);
112		- if (ret < 0) {
113		- u32 tmp32;
114		- cfpkt_extr_head(pkt, &tmp32, 4);
115		- }
116		- return ret;
	111	+ return layr->dn->transmit(layr->dn, pkt);
117	112	}
...	...	@@ -120,7 +120,6 @@
120	120	int tmp;
121	121	u16 chks;
122	122	u16 len;
123		- int ret;
124	123	struct cffrml *this = container_obj(layr);
125	124	if (this->dofcs) {
126	125	chks = cfpkt_iterate(pkt, cffrml_checksum, 0xffff);
...	...	@@ -137,12 +136,7 @@
137	136	pr_err("Packet is erroneous!\n");
138	137	return -EPROTO;
139	138	}
140		- ret = layr->dn->transmit(layr->dn, pkt);
141		- if (ret < 0) {
142		- /* Remove header on faulty packet. */
143		- cfpkt_extr_head(pkt, &tmp, 2);
144		- }
145		- return ret;
	139	+ return layr->dn->transmit(layr->dn, pkt);
146	140	}
147	141
148	142	static void cffrml_ctrlcmd(struct cflayer *layr, enum caif_ctrlcmd ctrl,
...	...	@@ -184,7 +184,6 @@
184	184
185	185	static int cfmuxl_transmit(struct cflayer layr, struct cfpkt pkt)
186	186	{
187		- int ret;
188	187	struct cfmuxl *muxl = container_obj(layr);
189	188	u8 linkid;
190	189	struct cflayer *dn;
...	...	@@ -198,11 +197,7 @@
198	197	info->hdr_len += 1;
199	198	linkid = info->channel_id;
200	199	cfpkt_add_head(pkt, &linkid, 1);
201		- ret = dn->transmit(dn, pkt);
202		- /* Remove MUX protocol header upon error. */
203		- if (ret < 0)
204		- cfpkt_extr_head(pkt, &linkid, 1);
205		- return ret;
	200	+ return dn->transmit(dn, pkt);
206	201	}
207	202
208	203	static void cfmuxl_ctrlcmd(struct cflayer *layr, enum caif_ctrlcmd ctrl,
...	...	@@ -179,15 +179,10 @@
179	179	static int cfserl_transmit(struct cflayer layer, struct cfpkt newpkt)
180	180	{
181	181	struct cfserl *layr = container_obj(layer);
182		- int ret;
183	182	u8 tmp8 = CFSERL_STX;
184	183	if (layr->usestx)
185	184	cfpkt_add_head(newpkt, &tmp8, 1);
186		- ret = layer->dn->transmit(layer->dn, newpkt);
187		- if (ret < 0)
188		- cfpkt_extr_head(newpkt, &tmp8, 1);
189		-
190		- return ret;
	185	+ return layer->dn->transmit(layer->dn, newpkt);
191	186	}
192	187
193	188	static void cfserl_ctrlcmd(struct cflayer *layr, enum caif_ctrlcmd ctrl,
...	...	@@ -100,11 +100,6 @@
100	100	*/
101	101	info->hdr_len = 1;
102	102	info->dev_info = &service->dev_info;
103		- ret = layr->dn->transmit(layr->dn, pkt);
104		- if (ret < 0) {
105		- u32 tmp32;
106		- cfpkt_extr_head(pkt, &tmp32, 4);
107		- }
108		- return ret;
	103	+ return layr->dn->transmit(layr->dn, pkt);
109	104	}
...	...	@@ -96,9 +96,6 @@
96	96	info->channel_id = service->layer.id;
97	97	info->hdr_len = 1;
98	98	info->dev_info = &service->dev_info;
99		- ret = layr->dn->transmit(layr->dn, pkt);
100		- if (ret < 0)
101		- cfpkt_extr_head(pkt, &tmp, 1);
102		- return ret;
	99	+ return layr->dn->transmit(layr->dn, pkt);
103	100	}
...	...	@@ -60,9 +60,6 @@
60	60	info = cfpkt_info(pkt);
61	61	info->channel_id = service->layer.id;
62	62	info->dev_info = &service->dev_info;
63		- ret = layr->dn->transmit(layr->dn, pkt);
64		- if (ret < 0)
65		- cfpkt_extr_head(pkt, &videoheader, 4);
66		- return ret;
	63	+ return layr->dn->transmit(layr->dn, pkt);
67	64	}