Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6
[pandora-kernel.git] / net / dccp / ccid.h
index 6df6f8a..75c3582 100644 (file)
@@ -62,22 +62,18 @@ struct ccid_operations {
        void            (*ccid_hc_tx_exit)(struct sock *sk);
        void            (*ccid_hc_rx_packet_recv)(struct sock *sk,
                                                  struct sk_buff *skb);
-       int             (*ccid_hc_rx_parse_options)(struct sock *sk,
-                                                   unsigned char option,
-                                                   unsigned char len, u16 idx,
-                                                   unsigned char* value);
+       int             (*ccid_hc_rx_parse_options)(struct sock *sk, u8 pkt,
+                                                   u8 opt, u8 *val, u8 len);
        int             (*ccid_hc_rx_insert_options)(struct sock *sk,
                                                     struct sk_buff *skb);
        void            (*ccid_hc_tx_packet_recv)(struct sock *sk,
                                                  struct sk_buff *skb);
-       int             (*ccid_hc_tx_parse_options)(struct sock *sk,
-                                                   unsigned char option,
-                                                   unsigned char len, u16 idx,
-                                                   unsigned char* value);
+       int             (*ccid_hc_tx_parse_options)(struct sock *sk, u8 pkt,
+                                                   u8 opt, u8 *val, u8 len);
        int             (*ccid_hc_tx_send_packet)(struct sock *sk,
                                                  struct sk_buff *skb);
        void            (*ccid_hc_tx_packet_sent)(struct sock *sk,
-                                                 int more, unsigned int len);
+                                                 unsigned int len);
        void            (*ccid_hc_rx_get_info)(struct sock *sk,
                                               struct tcp_info *info);
        void            (*ccid_hc_tx_get_info)(struct sock *sk,
@@ -138,20 +134,48 @@ static inline int ccid_get_current_tx_ccid(struct dccp_sock *dp)
 extern void ccid_hc_rx_delete(struct ccid *ccid, struct sock *sk);
 extern void ccid_hc_tx_delete(struct ccid *ccid, struct sock *sk);
 
+/*
+ * Congestion control of queued data packets via CCID decision.
+ *
+ * The TX CCID performs its congestion-control by indicating whether and when a
+ * queued packet may be sent, using the return code of ccid_hc_tx_send_packet().
+ * The following modes are supported via the symbolic constants below:
+ * - timer-based pacing    (CCID returns a delay value in milliseconds);
+ * - autonomous dequeueing (CCID internally schedules dccps_xmitlet).
+ */
+
+enum ccid_dequeueing_decision {
+       CCID_PACKET_SEND_AT_ONCE =       0x00000,  /* "green light": no delay */
+       CCID_PACKET_DELAY_MAX =          0x0FFFF,  /* maximum delay in msecs  */
+       CCID_PACKET_DELAY =              0x10000,  /* CCID msec-delay mode */
+       CCID_PACKET_WILL_DEQUEUE_LATER = 0x20000,  /* CCID autonomous mode */
+       CCID_PACKET_ERR =                0xF0000,  /* error condition */
+};
+
+static inline int ccid_packet_dequeue_eval(const int return_code)
+{
+       if (return_code < 0)
+               return CCID_PACKET_ERR;
+       if (return_code == 0)
+               return CCID_PACKET_SEND_AT_ONCE;
+       if (return_code <= CCID_PACKET_DELAY_MAX)
+               return CCID_PACKET_DELAY;
+       return return_code;
+}
+
 static inline int ccid_hc_tx_send_packet(struct ccid *ccid, struct sock *sk,
                                         struct sk_buff *skb)
 {
-       int rc = 0;
        if (ccid->ccid_ops->ccid_hc_tx_send_packet != NULL)
-               rc = ccid->ccid_ops->ccid_hc_tx_send_packet(sk, skb);
-       return rc;
+               return ccid->ccid_ops->ccid_hc_tx_send_packet(sk, skb);
+       return CCID_PACKET_SEND_AT_ONCE;
 }
 
 static inline void ccid_hc_tx_packet_sent(struct ccid *ccid, struct sock *sk,
-                                         int more, unsigned int len)
+                                         unsigned int len)
 {
        if (ccid->ccid_ops->ccid_hc_tx_packet_sent != NULL)
-               ccid->ccid_ops->ccid_hc_tx_packet_sent(sk, more, len);
+               ccid->ccid_ops->ccid_hc_tx_packet_sent(sk, len);
 }
 
 static inline void ccid_hc_rx_packet_recv(struct ccid *ccid, struct sock *sk,
@@ -168,27 +192,31 @@ static inline void ccid_hc_tx_packet_recv(struct ccid *ccid, struct sock *sk,
                ccid->ccid_ops->ccid_hc_tx_packet_recv(sk, skb);
 }
 
+/**
+ * ccid_hc_tx_parse_options  -  Parse CCID-specific options sent by the receiver
+ * @pkt: type of packet that @opt appears on (RFC 4340, 5.1)
+ * @opt: the CCID-specific option type (RFC 4340, 5.8 and 10.3)
+ * @val: value of @opt
+ * @len: length of @val in bytes
+ */
 static inline int ccid_hc_tx_parse_options(struct ccid *ccid, struct sock *sk,
-                                          unsigned char option,
-                                          unsigned char len, u16 idx,
-                                          unsigned char* value)
+                                          u8 pkt, u8 opt, u8 *val, u8 len)
 {
-       int rc = 0;
-       if (ccid->ccid_ops->ccid_hc_tx_parse_options != NULL)
-               rc = ccid->ccid_ops->ccid_hc_tx_parse_options(sk, option, len, idx,
-                                                   value);
-       return rc;
+       if (ccid->ccid_ops->ccid_hc_tx_parse_options == NULL)
+               return 0;
+       return ccid->ccid_ops->ccid_hc_tx_parse_options(sk, pkt, opt, val, len);
 }
 
+/**
+ * ccid_hc_rx_parse_options  -  Parse CCID-specific options sent by the sender
+ * Arguments are analogous to ccid_hc_tx_parse_options()
+ */
 static inline int ccid_hc_rx_parse_options(struct ccid *ccid, struct sock *sk,
-                                          unsigned char option,
-                                          unsigned char len, u16 idx,
-                                          unsigned char* value)
+                                          u8 pkt, u8 opt, u8 *val, u8 len)
 {
-       int rc = 0;
-       if (ccid->ccid_ops->ccid_hc_rx_parse_options != NULL)
-               rc = ccid->ccid_ops->ccid_hc_rx_parse_options(sk, option, len, idx, value);
-       return rc;
+       if (ccid->ccid_ops->ccid_hc_rx_parse_options == NULL)
+               return 0;
+       return ccid->ccid_ops->ccid_hc_rx_parse_options(sk, pkt, opt, val, len);
 }
 
 static inline int ccid_hc_rx_insert_options(struct ccid *ccid, struct sock *sk,