1 files changed, 151 insertions, 97 deletions

diff --git a/net/dccp/ccid.h b/net/dccp/ccid.h
index c37eeeaf5c6..6eb837a47b5 100644
--- a/net/dccp/ccid.h
+++ b/net/dccp/ccid.h
@@ -19,38 +19,61 @@
 #include <linux/list.h>
 #include <linux/module.h>
 
-#define CCID_MAX 255
+/* maximum value for a CCID (RFC 4340, 19.5) */
+#define CCID_MAX		255
+#define CCID_SLAB_NAME_LENGTH	32
 
-struct ccid {
-	unsigned char	ccid_id;
-	const char	*ccid_name;
-	struct module	*ccid_owner;
-	int		(*ccid_init)(struct sock *sk);
-	void		(*ccid_exit)(struct sock *sk);
-	int		(*ccid_hc_rx_init)(struct sock *sk);
-	int		(*ccid_hc_tx_init)(struct sock *sk);
+struct tcp_info;
+
+/**
+ *  struct ccid_operations  -  Interface to Congestion-Control Infrastructure
+ *
+ *  @ccid_id: numerical CCID ID (up to %CCID_MAX, cf. table 5 in RFC 4340, 10.)
+ *  @ccid_ccmps: the CCMPS including network/transport headers (0 when disabled)
+ *  @ccid_name: alphabetical identifier string for @ccid_id
+ *  @ccid_hc_{r,t}x_slab: memory pool for the receiver/sender half-connection
+ *  @ccid_hc_{r,t}x_obj_size: size of the receiver/sender half-connection socket
+ *
+ *  @ccid_hc_{r,t}x_init: CCID-specific initialisation routine (before startup)
+ *  @ccid_hc_{r,t}x_exit: CCID-specific cleanup routine (before destruction)
+ *  @ccid_hc_rx_packet_recv: implements the HC-receiver side
+ *  @ccid_hc_{r,t}x_parse_options: parsing routine for CCID/HC-specific options
+ *  @ccid_hc_{r,t}x_insert_options: insert routine for CCID/HC-specific options
+ *  @ccid_hc_tx_packet_recv: implements feedback processing for the HC-sender
+ *  @ccid_hc_tx_send_packet: implements the sending part of the HC-sender
+ *  @ccid_hc_tx_packet_sent: does accounting for packets in flight by HC-sender
+ *  @ccid_hc_{r,t}x_get_info: INET_DIAG information for HC-receiver/sender
+ *  @ccid_hc_{r,t}x_getsockopt: socket options specific to HC-receiver/sender
+ */
+struct ccid_operations {
+	unsigned char		ccid_id;
+	__u32			ccid_ccmps;
+	const char		*ccid_name;
+	struct kmem_cache	*ccid_hc_rx_slab,
+				*ccid_hc_tx_slab;
+	char			ccid_hc_rx_slab_name[CCID_SLAB_NAME_LENGTH];
+	char			ccid_hc_tx_slab_name[CCID_SLAB_NAME_LENGTH];
+	__u32			ccid_hc_rx_obj_size,
+				ccid_hc_tx_obj_size;
+	/* Interface Routines */
+	int		(*ccid_hc_rx_init)(struct ccid *ccid, struct sock *sk);
+	int		(*ccid_hc_tx_init)(struct ccid *ccid, struct sock *sk);
 	void		(*ccid_hc_rx_exit)(struct sock *sk);
 	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);
-	void		(*ccid_hc_rx_insert_options)(struct sock *sk,
-						     struct sk_buff *skb);
-	void		(*ccid_hc_tx_insert_options)(struct sock *sk,
+	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, int len);
-	void		(*ccid_hc_tx_packet_sent)(struct sock *sk, int more,
-						  int len);
+						  struct sk_buff *skb);
+	void		(*ccid_hc_tx_packet_sent)(struct sock *sk,
+						  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,
@@ -65,126 +88,157 @@ struct ccid {
 						 int __user *optlen);
 };
 
-extern int	   ccid_register(struct ccid *ccid);
-extern int	   ccid_unregister(struct ccid *ccid);
+extern struct ccid_operations ccid2_ops;
+#ifdef CONFIG_IP_DCCP_CCID3
+extern struct ccid_operations ccid3_ops;
+#endif
 
-extern struct ccid *ccid_init(unsigned char id, struct sock *sk);
-extern void	   ccid_exit(struct ccid *ccid, struct sock *sk);
+int ccid_initialize_builtins(void);
+void ccid_cleanup_builtins(void);
 
-static inline void __ccid_get(struct ccid *ccid)
-{
-	__module_get(ccid->ccid_owner);
-}
+struct ccid {
+	struct ccid_operations *ccid_ops;
+	char		       ccid_priv[0];
+};
 
-static inline int ccid_hc_tx_send_packet(struct ccid *ccid, struct sock *sk,
-					 struct sk_buff *skb, int len)
+static inline void *ccid_priv(const struct ccid *ccid)
 {
-	int rc = 0;
-	if (ccid->ccid_hc_tx_send_packet != NULL)
-		rc = ccid->ccid_hc_tx_send_packet(sk, skb, len);
-	return rc;
+	return (void *)ccid->ccid_priv;
 }
 
-static inline void ccid_hc_tx_packet_sent(struct ccid *ccid, struct sock *sk,
-					  int more, int len)
+bool ccid_support_check(u8 const *ccid_array, u8 array_len);
+int ccid_get_builtin_ccids(u8 **ccid_array, u8 *array_len);
+int ccid_getsockopt_builtin_ccids(struct sock *sk, int len,
+				  char __user *, int __user *);
+
+struct ccid *ccid_new(const u8 id, struct sock *sk, bool rx);
+
+static inline int ccid_get_current_rx_ccid(struct dccp_sock *dp)
 {
-	if (ccid->ccid_hc_tx_packet_sent != NULL)
-		ccid->ccid_hc_tx_packet_sent(sk, more, len);
+	struct ccid *ccid = dp->dccps_hc_rx_ccid;
+
+	if (ccid == NULL || ccid->ccid_ops == NULL)
+		return -1;
+	return ccid->ccid_ops->ccid_id;
 }
 
-static inline int ccid_hc_rx_init(struct ccid *ccid, struct sock *sk)
+static inline int ccid_get_current_tx_ccid(struct dccp_sock *dp)
 {
-	int rc = 0;
-	if (ccid->ccid_hc_rx_init != NULL)
-		rc = ccid->ccid_hc_rx_init(sk);
-	return rc;
+	struct ccid *ccid = dp->dccps_hc_tx_ccid;
+
+	if (ccid == NULL || ccid->ccid_ops == NULL)
+		return -1;
+	return ccid->ccid_ops->ccid_id;
 }
 
-static inline int ccid_hc_tx_init(struct ccid *ccid, struct sock *sk)
+void ccid_hc_rx_delete(struct ccid *ccid, struct sock *sk);
+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)
 {
-	int rc = 0;
-	if (ccid->ccid_hc_tx_init != NULL)
-		rc = ccid->ccid_hc_tx_init(sk);
-	return rc;
+	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 void ccid_hc_rx_exit(struct ccid *ccid, struct sock *sk)
+static inline int ccid_hc_tx_send_packet(struct ccid *ccid, struct sock *sk,
+					 struct sk_buff *skb)
 {
-	if (ccid != NULL && ccid->ccid_hc_rx_exit != NULL &&
-	    dccp_sk(sk)->dccps_hc_rx_ccid_private != NULL)
-		ccid->ccid_hc_rx_exit(sk);
+	if (ccid->ccid_ops->ccid_hc_tx_send_packet != NULL)
+		return ccid->ccid_ops->ccid_hc_tx_send_packet(sk, skb);
+	return CCID_PACKET_SEND_AT_ONCE;
 }
 
-static inline void ccid_hc_tx_exit(struct ccid *ccid, struct sock *sk)
+static inline void ccid_hc_tx_packet_sent(struct ccid *ccid, struct sock *sk,
+					  unsigned int len)
 {
-	if (ccid != NULL && ccid->ccid_hc_tx_exit != NULL &&
-	    dccp_sk(sk)->dccps_hc_tx_ccid_private != NULL)
-		ccid->ccid_hc_tx_exit(sk);
+	if (ccid->ccid_ops->ccid_hc_tx_packet_sent != NULL)
+		ccid->ccid_ops->ccid_hc_tx_packet_sent(sk, len);
 }
 
 static inline void ccid_hc_rx_packet_recv(struct ccid *ccid, struct sock *sk,
 					  struct sk_buff *skb)
 {
-	if (ccid->ccid_hc_rx_packet_recv != NULL)
-		ccid->ccid_hc_rx_packet_recv(sk, skb);
+	if (ccid->ccid_ops->ccid_hc_rx_packet_recv != NULL)
+		ccid->ccid_ops->ccid_hc_rx_packet_recv(sk, skb);
 }
 
 static inline void ccid_hc_tx_packet_recv(struct ccid *ccid, struct sock *sk,
 					  struct sk_buff *skb)
 {
-	if (ccid->ccid_hc_tx_packet_recv != NULL)
-		ccid->ccid_hc_tx_packet_recv(sk, skb);
+	if (ccid->ccid_ops->ccid_hc_tx_packet_recv != NULL)
+		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_hc_tx_parse_options != NULL)
-		rc = ccid->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)
-{
-	int rc = 0;
-	if (ccid->ccid_hc_rx_parse_options != NULL)
-		rc = ccid->ccid_hc_rx_parse_options(sk, option, len, idx, value);
-	return rc;
-}
-
-static inline void ccid_hc_tx_insert_options(struct ccid *ccid, struct sock *sk,
-					     struct sk_buff *skb)
+					   u8 pkt, u8 opt, u8 *val, u8 len)
 {
-	if (ccid->ccid_hc_tx_insert_options != NULL)
-		ccid->ccid_hc_tx_insert_options(sk, skb);
+	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 void ccid_hc_rx_insert_options(struct ccid *ccid, struct sock *sk,
-					     struct sk_buff *skb)
+static inline int ccid_hc_rx_insert_options(struct ccid *ccid, struct sock *sk,
+					    struct sk_buff *skb)
 {
-	if (ccid->ccid_hc_rx_insert_options != NULL)
-		ccid->ccid_hc_rx_insert_options(sk, skb);
+	if (ccid->ccid_ops->ccid_hc_rx_insert_options != NULL)
+		return ccid->ccid_ops->ccid_hc_rx_insert_options(sk, skb);
+	return 0;
 }
 
 static inline void ccid_hc_rx_get_info(struct ccid *ccid, struct sock *sk,
 				       struct tcp_info *info)
 {
-	if (ccid->ccid_hc_rx_get_info != NULL)
-		ccid->ccid_hc_rx_get_info(sk, info);
+	if (ccid->ccid_ops->ccid_hc_rx_get_info != NULL)
+		ccid->ccid_ops->ccid_hc_rx_get_info(sk, info);
 }
 
 static inline void ccid_hc_tx_get_info(struct ccid *ccid, struct sock *sk,
 				       struct tcp_info *info)
 {
-	if (ccid->ccid_hc_tx_get_info != NULL)
-		ccid->ccid_hc_tx_get_info(sk, info);
+	if (ccid->ccid_ops->ccid_hc_tx_get_info != NULL)
+		ccid->ccid_ops->ccid_hc_tx_get_info(sk, info);
 }
 
 static inline int ccid_hc_rx_getsockopt(struct ccid *ccid, struct sock *sk,
@@ -192,8 +246,8 @@ static inline int ccid_hc_rx_getsockopt(struct ccid *ccid, struct sock *sk,
 					u32 __user *optval, int __user *optlen)
 {
 	int rc = -ENOPROTOOPT;
-	if (ccid->ccid_hc_rx_getsockopt != NULL)
-		rc = ccid->ccid_hc_rx_getsockopt(sk, optname, len,
+	if (ccid != NULL && ccid->ccid_ops->ccid_hc_rx_getsockopt != NULL)
+		rc = ccid->ccid_ops->ccid_hc_rx_getsockopt(sk, optname, len,
 						 optval, optlen);
 	return rc;
 }
@@ -203,8 +257,8 @@ static inline int ccid_hc_tx_getsockopt(struct ccid *ccid, struct sock *sk,
 					u32 __user *optval, int __user *optlen)
 {
 	int rc = -ENOPROTOOPT;
-	if (ccid->ccid_hc_tx_getsockopt != NULL)
-		rc = ccid->ccid_hc_tx_getsockopt(sk, optname, len,
+	if (ccid != NULL && ccid->ccid_ops->ccid_hc_tx_getsockopt != NULL)
+		rc = ccid->ccid_ops->ccid_hc_tx_getsockopt(sk, optname, len,
 						 optval, optlen);
 	return rc;
 }