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[DCCP]: Use `unsigned' for packet lengths

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This patch implements a suggestion by Ian McDonald and

 1) Avoids tests against negative packet lengths by using unsigned int
    for packet payload lengths in the CCID send_packet()/packet_sent() routines

 2) As a consequence, it removes an now unnecessary test with regard to `len > 0'
    in ccid3_hc_tx_packet_sent: that condition is always true, since
      * negative packet lengths are avoided
      * ccid3_hc_tx_send_packet flags an error whenever the payload length is 0.
        As a consequence, ccid3_hc_tx_packet_sent is never called as all errors
        returned by ccid_hc_tx_send_packet are caught in dccp_write_xmit

 3) Removes the third argument of ccid_hc_tx_send_packet (the `len' parameter),
    since it is currently always set to skb->len. The code is updated with regard
    to this parameter change.

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
This commit is contained in:
Gerrit Renker 2006-11-28 19:55:06 -02:00 committed by David S. Miller
parent a79ef76f4d
commit 6b57c93dc3
4 changed files with 48 additions and 58 deletions
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12
net/dccp/ccid.h
View File

@ -52,9 +52,9 @@ struct ccid_operations {
unsigned char len, u16 idx,
unsigned char* value);
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,
int more, 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,
@ -94,16 +94,16 @@ extern void ccid_hc_rx_delete(struct ccid *ccid, struct sock *sk);
extern void ccid_hc_tx_delete(struct ccid *ccid, struct sock *sk);
static inline int ccid_hc_tx_send_packet(struct ccid *ccid, struct sock *sk,
struct sk_buff *skb, int len)
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, len);
rc = ccid->ccid_ops->ccid_hc_tx_send_packet(sk, skb);
return rc;
}
static inline void ccid_hc_tx_packet_sent(struct ccid *ccid, struct sock *sk,
int more, int len)
int more, unsigned int len)
{
if (ccid->ccid_ops->ccid_hc_tx_packet_sent != NULL)
ccid->ccid_ops->ccid_hc_tx_packet_sent(sk, more, len);

5
net/dccp/ccids/ccid2.c
View File

@ -125,8 +125,7 @@ static int ccid2_hc_tx_alloc_seq(struct ccid2_hc_tx_sock *hctx, int num,
return 0;
}
static int ccid2_hc_tx_send_packet(struct sock *sk,
struct sk_buff *skb, int len)
static int ccid2_hc_tx_send_packet(struct sock *sk, struct sk_buff *skb)
{
struct ccid2_hc_tx_sock *hctx;
@ -268,7 +267,7 @@ static void ccid2_start_rto_timer(struct sock *sk)
jiffies + hctx->ccid2hctx_rto);
}
static void ccid2_hc_tx_packet_sent(struct sock *sk, int more, int len)
static void ccid2_hc_tx_packet_sent(struct sock *sk, int more, unsigned int len)
{
struct dccp_sock *dp = dccp_sk(sk);
struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk);

83
net/dccp/ccids/ccid3.c
View File

@ -272,8 +272,7 @@ out:
* = 0: can send immediately
* < 0: error condition; do not send packet
*/
static int ccid3_hc_tx_send_packet(struct sock *sk,
struct sk_buff *skb, int len)
static int ccid3_hc_tx_send_packet(struct sock *sk, struct sk_buff *skb)
{
struct dccp_sock *dp = dccp_sk(sk);
struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk);
@ -288,7 +287,7 @@ static int ccid3_hc_tx_send_packet(struct sock *sk,
* zero-sized Data(Ack)s is theoretically possible, but for congestion
* control this case is pathological - ignore it.
*/
if (unlikely(len == 0))
if (unlikely(skb->len == 0))
return -EBADMSG;
/* See if last packet allocated was not sent */
@ -317,7 +316,7 @@ static int ccid3_hc_tx_send_packet(struct sock *sk,
ccid3_hc_tx_set_state(sk, TFRC_SSTATE_NO_FBACK);
/* Set initial sending rate to 1 packet per second */
ccid3_hc_tx_update_s(hctx, len);
ccid3_hc_tx_update_s(hctx, skb->len);
hctx->ccid3hctx_x = hctx->ccid3hctx_s;
/* First timeout, according to [RFC 3448, 4.2], is 1 second */
@ -356,59 +355,53 @@ static int ccid3_hc_tx_send_packet(struct sock *sk,
return 0;
}
static void ccid3_hc_tx_packet_sent(struct sock *sk, int more, int len)
static void ccid3_hc_tx_packet_sent(struct sock *sk, int more, unsigned int len)
{
const struct dccp_sock *dp = dccp_sk(sk);
struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk);
struct timeval now;
unsigned long quarter_rtt;
struct dccp_tx_hist_entry *packet;
BUG_ON(hctx == NULL);
dccp_timestamp(sk, &now);
/* check if we have sent a data packet */
if (len > 0) {
unsigned long quarter_rtt;
struct dccp_tx_hist_entry *packet;
ccid3_hc_tx_update_s(hctx, len);
ccid3_hc_tx_update_s(hctx, len);
packet = dccp_tx_hist_head(&hctx->ccid3hctx_hist);
if (unlikely(packet == NULL)) {
DCCP_WARN("packet doesn't exist in history!\n");
return;
}
if (unlikely(packet->dccphtx_sent)) {
DCCP_WARN("no unsent packet in history!\n");
return;
}
packet->dccphtx_tstamp = now;
packet->dccphtx_seqno = dp->dccps_gss;
/*
* Check if win_count have changed
* Algorithm in "8.1. Window Counter Value" in RFC 4342.
*/
quarter_rtt = timeval_delta(&now, &hctx->ccid3hctx_t_last_win_count);
if (likely(hctx->ccid3hctx_rtt > 8))
quarter_rtt /= hctx->ccid3hctx_rtt / 4;
packet = dccp_tx_hist_head(&hctx->ccid3hctx_hist);
if (unlikely(packet == NULL)) {
DCCP_WARN("packet doesn't exist in history!\n");
return;
}
if (unlikely(packet->dccphtx_sent)) {
DCCP_WARN("no unsent packet in history!\n");
return;
}
packet->dccphtx_tstamp = now;
packet->dccphtx_seqno = dp->dccps_gss;
/*
* Check if win_count have changed
* Algorithm in "8.1. Window Counter Value" in RFC 4342.
*/
quarter_rtt = timeval_delta(&now, &hctx->ccid3hctx_t_last_win_count);
if (likely(hctx->ccid3hctx_rtt > 8))
quarter_rtt /= hctx->ccid3hctx_rtt / 4;
if (quarter_rtt > 0) {
hctx->ccid3hctx_t_last_win_count = now;
hctx->ccid3hctx_last_win_count = (hctx->ccid3hctx_last_win_count +
min_t(unsigned long, quarter_rtt, 5)) % 16;
ccid3_pr_debug("%s, sk=%p, window changed from "
"%u to %u!\n",
dccp_role(sk), sk,
packet->dccphtx_ccval,
hctx->ccid3hctx_last_win_count);
}
if (quarter_rtt > 0) {
hctx->ccid3hctx_t_last_win_count = now;
hctx->ccid3hctx_last_win_count = (hctx->ccid3hctx_last_win_count +
min_t(unsigned long, quarter_rtt, 5)) % 16;
ccid3_pr_debug("%s, sk=%p, window changed from "
"%u to %u!\n",
dccp_role(sk), sk,
packet->dccphtx_ccval,
hctx->ccid3hctx_last_win_count);
}
hctx->ccid3hctx_idle = 0;
packet->dccphtx_rtt = hctx->ccid3hctx_rtt;
packet->dccphtx_sent = 1;
} else
ccid3_pr_debug("%s, sk=%p, seqno=%llu NOT inserted!\n",
dccp_role(sk), sk, dp->dccps_gss);
hctx->ccid3hctx_idle = 0;
packet->dccphtx_rtt = hctx->ccid3hctx_rtt;
packet->dccphtx_sent = 1;
}
static void ccid3_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb)

6
net/dccp/output.c
View File

@ -195,8 +195,7 @@ static int dccp_wait_for_ccid(struct sock *sk, struct sk_buff *skb,
if (signal_pending(current))
goto do_interrupted;
rc = ccid_hc_tx_send_packet(dp->dccps_hc_tx_ccid, sk, skb,
skb->len);
rc = ccid_hc_tx_send_packet(dp->dccps_hc_tx_ccid, sk, skb);
if (rc <= 0)
break;
delay = msecs_to_jiffies(rc);
@ -245,8 +244,7 @@ void dccp_write_xmit(struct sock *sk, int block)
this we have other issues */
while ((skb = skb_peek(&sk->sk_write_queue))) {
int err = ccid_hc_tx_send_packet(dp->dccps_hc_tx_ccid, sk, skb,
skb->len);
int err = ccid_hc_tx_send_packet(dp->dccps_hc_tx_ccid, sk, skb);
if (err > 0) {
if (!block) {