caif: Use link layer MTU instead of fixed MTU
Previously CAIF supported maximum transfer size of ~4050.
The transfer size is now calculated dynamically based on the
link layers mtu size.
Signed-off-by: Sjur Braendeland@stericsson.com
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/caif/caif_socket.c b/net/caif/caif_socket.c
index 848ae75..8ce9047 100644
--- a/net/caif/caif_socket.c
+++ b/net/caif/caif_socket.c
@@ -28,8 +28,8 @@
MODULE_LICENSE("GPL");
MODULE_ALIAS_NETPROTO(AF_CAIF);
-#define CAIF_DEF_SNDBUF (CAIF_MAX_PAYLOAD_SIZE*10)
-#define CAIF_DEF_RCVBUF (CAIF_MAX_PAYLOAD_SIZE*100)
+#define CAIF_DEF_SNDBUF (4096*10)
+#define CAIF_DEF_RCVBUF (4096*100)
/*
* CAIF state is re-using the TCP socket states.
@@ -76,6 +76,7 @@
struct caif_connect_request conn_req;
struct mutex readlock;
struct dentry *debugfs_socket_dir;
+ int headroom, tailroom, maxframe;
};
static int rx_flow_is_on(struct caifsock *cf_sk)
@@ -594,23 +595,32 @@
goto err;
noblock = msg->msg_flags & MSG_DONTWAIT;
- buffer_size = len + CAIF_NEEDED_HEADROOM + CAIF_NEEDED_TAILROOM;
-
timeo = sock_sndtimeo(sk, noblock);
timeo = caif_wait_for_flow_on(container_of(sk, struct caifsock, sk),
1, timeo, &ret);
+ if (ret)
+ goto err;
ret = -EPIPE;
if (cf_sk->sk.sk_state != CAIF_CONNECTED ||
sock_flag(sk, SOCK_DEAD) ||
(sk->sk_shutdown & RCV_SHUTDOWN))
goto err;
+ /* Error if trying to write more than maximum frame size. */
+ ret = -EMSGSIZE;
+ if (len > cf_sk->maxframe && cf_sk->sk.sk_protocol != CAIFPROTO_RFM)
+ goto err;
+
+ buffer_size = len + cf_sk->headroom + cf_sk->tailroom;
+
ret = -ENOMEM;
skb = sock_alloc_send_skb(sk, buffer_size, noblock, &ret);
- if (!skb)
+
+ if (!skb || skb_tailroom(skb) < buffer_size)
goto err;
- skb_reserve(skb, CAIF_NEEDED_HEADROOM);
+
+ skb_reserve(skb, cf_sk->headroom);
ret = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len);
@@ -641,7 +651,6 @@
long timeo;
err = -EOPNOTSUPP;
-
if (unlikely(msg->msg_flags&MSG_OOB))
goto out_err;
@@ -658,8 +667,8 @@
size = len-sent;
- if (size > CAIF_MAX_PAYLOAD_SIZE)
- size = CAIF_MAX_PAYLOAD_SIZE;
+ if (size > cf_sk->maxframe)
+ size = cf_sk->maxframe;
/* If size is more than half of sndbuf, chop up message */
if (size > ((sk->sk_sndbuf >> 1) - 64))
@@ -669,14 +678,14 @@
size = SKB_MAX_ALLOC;
skb = sock_alloc_send_skb(sk,
- size + CAIF_NEEDED_HEADROOM
- + CAIF_NEEDED_TAILROOM,
+ size + cf_sk->headroom +
+ cf_sk->tailroom,
msg->msg_flags&MSG_DONTWAIT,
&err);
if (skb == NULL)
goto out_err;
- skb_reserve(skb, CAIF_NEEDED_HEADROOM);
+ skb_reserve(skb, cf_sk->headroom);
/*
* If you pass two values to the sock_alloc_send_skb
* it tries to grab the large buffer with GFP_NOFS
@@ -817,17 +826,15 @@
struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
long timeo;
int err;
+ int ifindex, headroom, tailroom;
+ struct net_device *dev;
+
lock_sock(sk);
err = -EAFNOSUPPORT;
if (uaddr->sa_family != AF_CAIF)
goto out;
- err = -ESOCKTNOSUPPORT;
- if (unlikely(!(sk->sk_type == SOCK_STREAM &&
- cf_sk->sk.sk_protocol == CAIFPROTO_AT) &&
- sk->sk_type != SOCK_SEQPACKET))
- goto out;
switch (sock->state) {
case SS_UNCONNECTED:
/* Normal case, a fresh connect */
@@ -883,12 +890,23 @@
dbfs_atomic_inc(&cnt.num_connect_req);
cf_sk->layer.receive = caif_sktrecv_cb;
err = caif_connect_client(&cf_sk->conn_req,
- &cf_sk->layer);
+ &cf_sk->layer, &ifindex, &headroom, &tailroom);
if (err < 0) {
cf_sk->sk.sk_socket->state = SS_UNCONNECTED;
cf_sk->sk.sk_state = CAIF_DISCONNECTED;
goto out;
}
+ dev = dev_get_by_index(sock_net(sk), ifindex);
+ cf_sk->headroom = LL_RESERVED_SPACE_EXTRA(dev, headroom);
+ cf_sk->tailroom = tailroom;
+ cf_sk->maxframe = dev->mtu - (headroom + tailroom);
+ dev_put(dev);
+ if (cf_sk->maxframe < 1) {
+ pr_warning("CAIF: %s(): CAIF Interface MTU too small (%d)\n",
+ __func__, dev->mtu);
+ err = -ENODEV;
+ goto out;
+ }
err = -EINPROGRESS;
wait_connect: