dccp: Fix sparse warnings

This patch fixes the following sparse warnings:
 * nested min(max()) expression:
   net/dccp/ccids/ccid3.c:91:21: warning: symbol '__x' shadows an earlier one
   net/dccp/ccids/ccid3.c:91:21: warning: symbol '__y' shadows an earlier one
   
 * Declaration of function prototypes in .c instead of .h file, resulting in
   "should it be static?" warnings. 

 * Declared "struct dccpw" static (local to dccp_probe).
 
 * Disabled dccp_delayed_ack() - not fully removed due to RFC 4340, 11.3
   ("Receivers SHOULD implement delayed acknowledgement timers ...").

 * Used a different local variable name to avoid
   net/dccp/ackvec.c:293:13: warning: symbol 'state' shadows an earlier one
   net/dccp/ackvec.c:238:33: originally declared here

 * Removed unused functions `dccp_ackvector_print' and `dccp_ackvec_print'.

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>

6 files changed, 16 insertions, 40 deletions

diff --git a/net/dccp/ackvec.c b/net/dccp/ackvec.c
index 6de4bd195d28..1e8be246ad15 100644
--- a/net/dccp/ackvec.c
+++ b/net/dccp/ackvec.c
@@ -290,12 +290,12 @@ int dccp_ackvec_add(struct dccp_ackvec *av, const struct sock *sk,
 
                 while (1) {
                         const u8 len = dccp_ackvec_len(av, index);
-                        const u8 state = dccp_ackvec_state(av, index);
+                        const u8 av_state = dccp_ackvec_state(av, index);
                         /*
                          * valid packets not yet in av_buf have a reserved
                          * entry, with a len equal to 0.
                          */
-                        if (state == DCCP_ACKVEC_STATE_NOT_RECEIVED &&
+                        if (av_state == DCCP_ACKVEC_STATE_NOT_RECEIVED &&
                             len == 0 && delta == 0) { /* Found our
                                                          reserved seat! */
                                 dccp_pr_debug("Found %llu reserved seat!\n",
@@ -325,31 +325,6 @@ out_duplicate:
         return -EILSEQ;
 }
 
-#ifdef CONFIG_IP_DCCP_DEBUG
-void dccp_ackvector_print(const u64 ackno, const unsigned char *vector, int len)
-{
-        dccp_pr_debug_cat("ACK vector len=%d, ackno=%llu |", len,
-                         (unsigned long long)ackno);
-
-        while (len--) {
-                const u8 state = (*vector & DCCP_ACKVEC_STATE_MASK) >> 6;
-                const u8 rl = *vector & DCCP_ACKVEC_LEN_MASK;
-
-                dccp_pr_debug_cat("%d,%d|", state, rl);
-                ++vector;
-        }
-
-        dccp_pr_debug_cat("\n");
-}
-
-void dccp_ackvec_print(const struct dccp_ackvec *av)
-{
-        dccp_ackvector_print(av->av_buf_ackno,
-                             av->av_buf + av->av_buf_head,
-                             av->av_vec_len);
-}
-#endif
-
 static void dccp_ackvec_throw_record(struct dccp_ackvec *av,
                                      struct dccp_ackvec_record *avr)
 {
diff --git a/net/dccp/ccids/ccid3.c b/net/dccp/ccids/ccid3.c
index 0474f4c5707a..a1929f33d703 100644
--- a/net/dccp/ccids/ccid3.c
+++ b/net/dccp/ccids/ccid3.c
@@ -159,8 +159,8 @@ static void ccid3_hc_tx_update_x(struct sock *sk, ktime_t *stamp)
         } else if (ktime_us_delta(now, hctx->ccid3hctx_t_ld)
                                 - (s64)hctx->ccid3hctx_rtt >= 0) {
 
-                hctx->ccid3hctx_x =
-                        max(min(2 * hctx->ccid3hctx_x, min_rate),
+                hctx->ccid3hctx_x = min(2 * hctx->ccid3hctx_x, min_rate);
+                hctx->ccid3hctx_x = max(hctx->ccid3hctx_x,
                             scaled_div(((__u64)hctx->ccid3hctx_s) << 6,
                                        hctx->ccid3hctx_rtt));
                 hctx->ccid3hctx_t_ld = now;
diff --git a/net/dccp/ccids/lib/tfrc.c b/net/dccp/ccids/lib/tfrc.c
index d1dfbb8de64c..97ecec0a8e76 100644
--- a/net/dccp/ccids/lib/tfrc.c
+++ b/net/dccp/ccids/lib/tfrc.c
@@ -14,14 +14,6 @@ module_param(tfrc_debug, bool, 0444);
 MODULE_PARM_DESC(tfrc_debug, "Enable debug messages");
 #endif
 
-extern int  tfrc_tx_packet_history_init(void);
-extern void tfrc_tx_packet_history_exit(void);
-extern int  tfrc_rx_packet_history_init(void);
-extern void tfrc_rx_packet_history_exit(void);
-
-extern int  tfrc_li_init(void);
-extern void tfrc_li_exit(void);
-
 static int __init tfrc_module_init(void)
 {
         int rc = tfrc_li_init();
diff --git a/net/dccp/ccids/lib/tfrc.h b/net/dccp/ccids/lib/tfrc.h
index 1fb1187bbf1c..ddd8107b927f 100644
--- a/net/dccp/ccids/lib/tfrc.h
+++ b/net/dccp/ccids/lib/tfrc.h
@@ -58,7 +58,14 @@ static inline u32 tfrc_ewma(const u32 avg, const u32 newval, const u8 weight)
         return avg ? (weight * avg + (10 - weight) * newval) / 10 : newval;
 }
 
-extern u32 tfrc_calc_x(u16 s, u32 R, u32 p);
-extern u32 tfrc_calc_x_reverse_lookup(u32 fvalue);
+extern u32  tfrc_calc_x(u16 s, u32 R, u32 p);
+extern u32  tfrc_calc_x_reverse_lookup(u32 fvalue);
 
+extern int  tfrc_tx_packet_history_init(void);
+extern void tfrc_tx_packet_history_exit(void);
+extern int  tfrc_rx_packet_history_init(void);
+extern void tfrc_rx_packet_history_exit(void);
+
+extern int  tfrc_li_init(void);
+extern void tfrc_li_exit(void);
 #endif /* _TFRC_H_ */
diff --git a/net/dccp/output.c b/net/dccp/output.c
index 1f8a9b64c083..fe20068c5d8e 100644
--- a/net/dccp/output.c
+++ b/net/dccp/output.c
@@ -508,6 +508,7 @@ void dccp_send_ack(struct sock *sk)
 
 EXPORT_SYMBOL_GPL(dccp_send_ack);
 
+#if 0
 /* FIXME: Is this still necessary (11.3) - currently nowhere used by DCCP. */
 void dccp_send_delayed_ack(struct sock *sk)
 {
@@ -538,6 +539,7 @@ void dccp_send_delayed_ack(struct sock *sk)
         icsk->icsk_ack.timeout = timeout;
         sk_reset_timer(sk, &icsk->icsk_delack_timer, timeout);
 }
+#endif
 
 void dccp_send_sync(struct sock *sk, const u64 ackno,
                     const enum dccp_pkt_type pkt_type)
diff --git a/net/dccp/probe.c b/net/dccp/probe.c
index 0bcdc9250279..81368a7f5379 100644
--- a/net/dccp/probe.c
+++ b/net/dccp/probe.c
@@ -42,7 +42,7 @@ static int bufsize = 64 * 1024;
 
 static const char procname[] = "dccpprobe";
 
-struct {
+static struct {
         struct kfifo      *fifo;
         spinlock_t        lock;
         wait_queue_head_t wait;