]> pilppa.org Git - linux-2.6-omap-h63xx.git/blobdiff - net/dccp/ackvec.c
[DCCP]: Simplified conditions due to use of enum:8 states
[linux-2.6-omap-h63xx.git] / net / dccp / ackvec.c
index 8c211c58893b2a6de115110743ed33a88befbe4d..1b4b60d8bdec89acedbf8314d3aab1f034f08dfe 100644 (file)
@@ -67,10 +67,6 @@ static void dccp_ackvec_insert_avr(struct dccp_ackvec *av,
 int dccp_insert_option_ackvec(struct sock *sk, struct sk_buff *skb)
 {
        struct dccp_sock *dp = dccp_sk(sk);
-#ifdef CONFIG_IP_DCCP_DEBUG
-       const char *debug_prefix = dp->dccps_role == DCCP_ROLE_CLIENT ?
-                               "CLIENT tx: " : "server tx: ";
-#endif
        struct dccp_ackvec *av = dp->dccps_hc_rx_ackvec;
        int len = av->dccpav_vec_len + 2;
        struct timeval now;
@@ -113,7 +109,7 @@ int dccp_insert_option_ackvec(struct sock *sk, struct sk_buff *skb)
 
        memcpy(to, from, len);
        /*
-        *      From draft-ietf-dccp-spec-11.txt:
+        *      From RFC 4340, A.2:
         *
         *      For each acknowledgement it sends, the HC-Receiver will add an
         *      acknowledgement record.  ack_seqno will equal the HC-Receiver
@@ -129,9 +125,9 @@ int dccp_insert_option_ackvec(struct sock *sk, struct sk_buff *skb)
 
        dccp_ackvec_insert_avr(av, avr);
 
-       dccp_pr_debug("%sACK Vector 0, len=%d, ack_seqno=%llu, "
+       dccp_pr_debug("%s ACK Vector 0, len=%d, ack_seqno=%llu, "
                      "ack_ackno=%llu\n",
-                     debug_prefix, avr->dccpavr_sent_len,
+                     dccp_role(sk), avr->dccpavr_sent_len,
                      (unsigned long long)avr->dccpavr_ack_seqno,
                      (unsigned long long)avr->dccpavr_ack_ackno);
        return 0;
@@ -142,14 +138,13 @@ struct dccp_ackvec *dccp_ackvec_alloc(const gfp_t priority)
        struct dccp_ackvec *av = kmem_cache_alloc(dccp_ackvec_slab, priority);
 
        if (av != NULL) {
-               av->dccpav_buf_head     =
-                       av->dccpav_buf_tail = DCCP_MAX_ACKVEC_LEN - 1;
+               av->dccpav_buf_head     = DCCP_MAX_ACKVEC_LEN - 1;
                av->dccpav_buf_ackno    = DCCP_MAX_SEQNO + 1;
                av->dccpav_buf_nonce = av->dccpav_buf_nonce = 0;
                av->dccpav_ack_ptr      = 0;
                av->dccpav_time.tv_sec  = 0;
                av->dccpav_time.tv_usec = 0;
-               av->dccpav_sent_len     = av->dccpav_vec_len = 0;
+               av->dccpav_vec_len      = 0;
                INIT_LIST_HEAD(&av->dccpav_records);
        }
 
@@ -225,7 +220,7 @@ static inline int dccp_ackvec_set_buf_head_state(struct dccp_ackvec *av,
 }
 
 /*
- * Implements the draft-ietf-dccp-spec-11.txt Appendix A
+ * Implements the RFC 4340, Appendix A
  */
 int dccp_ackvec_add(struct dccp_ackvec *av, const struct sock *sk,
                    const u64 ackno, const u8 state)
@@ -238,7 +233,7 @@ int dccp_ackvec_add(struct dccp_ackvec *av, const struct sock *sk,
         * We may well decide to do buffer compression, etc, but for now lets
         * just drop.
         *
-        * From Appendix A:
+        * From Appendix A.1.1 (`New Packets'):
         *
         *      Of course, the circular buffer may overflow, either when the
         *      HC-Sender is sending data at a very high rate, when the
@@ -275,9 +270,9 @@ int dccp_ackvec_add(struct dccp_ackvec *av, const struct sock *sk,
                /*
                 * A.1.2.  Old Packets
                 *
-                *      When a packet with Sequence Number S arrives, and
-                *      S <= buf_ackno, the HC-Receiver will scan the table
-                *      for the byte corresponding to S. (Indexing structures
+                *      When a packet with Sequence Number S <= buf_ackno
+                *      arrives, the HC-Receiver will scan the table for
+                *      the byte corresponding to S. (Indexing structures
                 *      could reduce the complexity of this scan.)
                 */
                u64 delta = dccp_delta_seqno(ackno, av->dccpav_buf_ackno);
@@ -323,21 +318,18 @@ out_duplicate:
 #ifdef CONFIG_IP_DCCP_DEBUG
 void dccp_ackvector_print(const u64 ackno, const unsigned char *vector, int len)
 {
-       if (!dccp_debug)
-               return;
-
-       printk("ACK vector len=%d, ackno=%llu |", len,
-              (unsigned long long)ackno);
+       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;
 
-               printk("%d,%d|", state, rl);
+               dccp_pr_debug_cat("%d,%d|", state, rl);
                ++vector;
        }
 
-       printk("\n");
+       dccp_pr_debug_cat("\n");
 }
 
 void dccp_ackvec_print(const struct dccp_ackvec *av)
@@ -353,11 +345,13 @@ static void dccp_ackvec_throw_record(struct dccp_ackvec *av,
 {
        struct dccp_ackvec_record *next;
 
-       av->dccpav_buf_tail = avr->dccpavr_ack_ptr - 1;
-       if (av->dccpav_buf_tail == 0)
-               av->dccpav_buf_tail = DCCP_MAX_ACKVEC_LEN - 1;
-
-       av->dccpav_vec_len -= avr->dccpavr_sent_len;
+       /* sort out vector length */
+       if (av->dccpav_buf_head <= avr->dccpavr_ack_ptr)
+               av->dccpav_vec_len = avr->dccpavr_ack_ptr - av->dccpav_buf_head;
+       else
+               av->dccpav_vec_len = DCCP_MAX_ACKVEC_LEN - 1
+                                    - av->dccpav_buf_head
+                                    + avr->dccpavr_ack_ptr;
 
        /* free records */
        list_for_each_entry_safe_from(avr, next, &av->dccpav_records,
@@ -379,19 +373,15 @@ void dccp_ackvec_check_rcv_ackno(struct dccp_ackvec *av, struct sock *sk,
         */
        list_for_each_entry_reverse(avr, &av->dccpav_records, dccpavr_node) {
                if (ackno == avr->dccpavr_ack_seqno) {
-#ifdef CONFIG_IP_DCCP_DEBUG
-                       struct dccp_sock *dp = dccp_sk(sk);
-                       const char *debug_prefix = dp->dccps_role == DCCP_ROLE_CLIENT ?
-                                               "CLIENT rx ack: " : "server rx ack: ";
-#endif
-                       dccp_pr_debug("%sACK packet 0, len=%d, ack_seqno=%llu, "
+                       dccp_pr_debug("%s ACK packet 0, len=%d, ack_seqno=%llu, "
                                      "ack_ackno=%llu, ACKED!\n",
-                                     debug_prefix, 1,
+                                     dccp_role(sk), 1,
                                      (unsigned long long)avr->dccpavr_ack_seqno,
                                      (unsigned long long)avr->dccpavr_ack_ackno);
                        dccp_ackvec_throw_record(av, avr);
                        break;
-               }
+               } else if (avr->dccpavr_ack_seqno > ackno)
+                       break; /* old news */
        }
 }
 
@@ -434,19 +424,12 @@ static void dccp_ackvec_check_rcv_ackvector(struct dccp_ackvec *av,
                break;
 found:
                if (between48(avr->dccpavr_ack_seqno, ackno_end_rl, ackno)) {
-                       const u8 state = (*vector &
-                                         DCCP_ACKVEC_STATE_MASK) >> 6;
+                       const u8 state = *vector & DCCP_ACKVEC_STATE_MASK;
                        if (state != DCCP_ACKVEC_STATE_NOT_RECEIVED) {
-#ifdef CONFIG_IP_DCCP_DEBUG
-                               struct dccp_sock *dp = dccp_sk(sk);
-                               const char *debug_prefix =
-                                       dp->dccps_role == DCCP_ROLE_CLIENT ?
-                                       "CLIENT rx ack: " : "server rx ack: ";
-#endif
-                               dccp_pr_debug("%sACK vector 0, len=%d, "
+                               dccp_pr_debug("%s ACK vector 0, len=%d, "
                                              "ack_seqno=%llu, ack_ackno=%llu, "
                                              "ACKED!\n",
-                                             debug_prefix, len,
+                                             dccp_role(sk), len,
                                              (unsigned long long)
                                              avr->dccpavr_ack_seqno,
                                              (unsigned long long)
@@ -478,9 +461,6 @@ int dccp_ackvec_parse(struct sock *sk, const struct sk_buff *skb,
        return 0;
 }
 
-static char dccp_ackvec_slab_msg[] __initdata =
-       KERN_CRIT "DCCP: Unable to create ack vectors slab caches\n";
-
 int __init dccp_ackvec_init(void)
 {
        dccp_ackvec_slab = kmem_cache_create("dccp_ackvec",
@@ -502,7 +482,7 @@ out_destroy_slab:
        kmem_cache_destroy(dccp_ackvec_slab);
        dccp_ackvec_slab = NULL;
 out_err:
-       printk(dccp_ackvec_slab_msg);
+       DCCP_CRIT("Unable to create Ack Vector slab cache");
        return -ENOBUFS;
 }