[DCCP] ackvec: infrastructure for sending more than one ackvec per packet
Commiter note:
This was split from Andrea's original patch, in the process I changed the type
of the ackvec index fields to u16 instead of to int and haven't folded
dccp_ackvec_parse with dccp_ackvec_check_rcv_ackno.
Next patch will actually do the insertion of more than one ackvec per packet,
using, initially, up to a max of 2 ackvecs as per Andrea's original patch, then
I'll work on support for larger ackvecs, be it using a sysctl or using
setsockopt.
Signed-off-by: Andrea Bittau <a.bittau@cs.ucl.ac.uk>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
diff --git a/net/dccp/ackvec.h b/net/dccp/ackvec.h
index d6a58db..96504a3 100644
--- a/net/dccp/ackvec.h
+++ b/net/dccp/ackvec.h
@@ -17,7 +17,9 @@
#include <linux/types.h>
/* Read about the ECN nonce to see why it is 253 */
-#define DCCP_MAX_ACKVEC_LEN 253
+#define DCCP_MAX_ACKVEC_OPT_LEN 253
+/* We can spread an ack vector across multiple options */
+#define DCCP_MAX_ACKVEC_LEN (DCCP_MAX_ACKVEC_OPT_LEN * 2)
#define DCCP_ACKVEC_STATE_RECEIVED 0
#define DCCP_ACKVEC_STATE_ECN_MARKED (1 << 6)
@@ -51,8 +53,8 @@
u64 dccpav_buf_ackno;
struct list_head dccpav_records;
struct timeval dccpav_time;
- u8 dccpav_buf_head;
- u8 dccpav_vec_len;
+ u16 dccpav_buf_head;
+ u16 dccpav_vec_len;
u8 dccpav_buf_nonce;
u8 dccpav_ack_nonce;
u8 dccpav_buf[DCCP_MAX_ACKVEC_LEN];
@@ -75,9 +77,9 @@
struct list_head dccpavr_node;
u64 dccpavr_ack_seqno;
u64 dccpavr_ack_ackno;
- u8 dccpavr_ack_ptr;
+ u16 dccpavr_ack_ptr;
+ u16 dccpavr_sent_len;
u8 dccpavr_ack_nonce;
- u8 dccpavr_sent_len;
};
struct sock;
@@ -96,7 +98,8 @@
extern void dccp_ackvec_check_rcv_ackno(struct dccp_ackvec *av,
struct sock *sk, const u64 ackno);
extern int dccp_ackvec_parse(struct sock *sk, const struct sk_buff *skb,
- const u8 opt, const u8 *value, const u8 len);
+ u64 *ackno, const u8 opt,
+ const u8 *value, const u8 len);
extern int dccp_insert_option_ackvec(struct sock *sk, struct sk_buff *skb);
@@ -135,7 +138,8 @@
}
static inline int dccp_ackvec_parse(struct sock *sk, const struct sk_buff *skb,
- const u8 opt, const u8 *value, const u8 len)
+ const u64 *ackno, const u8 opt,
+ const u8 *value, const u8 len)
{
return -1;
}