Merge branch 'dccp' of git://eden-feed.erg.abdn.ac.uk/net-next-2.6
This commit is contained in:
Коммит
ed1deb7021
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@ -1,7 +1,8 @@
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/*
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* net/dccp/ackvec.c
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*
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* An implementation of the DCCP protocol
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* An implementation of Ack Vectors for the DCCP protocol
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* Copyright (c) 2007 University of Aberdeen, Scotland, UK
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* Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
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*
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* This program is free software; you can redistribute it and/or modify it
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@ -23,173 +24,93 @@
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static struct kmem_cache *dccp_ackvec_slab;
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static struct kmem_cache *dccp_ackvec_record_slab;
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static struct dccp_ackvec_record *dccp_ackvec_record_new(void)
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{
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struct dccp_ackvec_record *avr =
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kmem_cache_alloc(dccp_ackvec_record_slab, GFP_ATOMIC);
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if (avr != NULL)
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INIT_LIST_HEAD(&avr->avr_node);
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return avr;
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}
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static void dccp_ackvec_record_delete(struct dccp_ackvec_record *avr)
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{
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if (unlikely(avr == NULL))
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return;
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/* Check if deleting a linked record */
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WARN_ON(!list_empty(&avr->avr_node));
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kmem_cache_free(dccp_ackvec_record_slab, avr);
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}
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static void dccp_ackvec_insert_avr(struct dccp_ackvec *av,
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struct dccp_ackvec_record *avr)
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{
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/*
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* AVRs are sorted by seqno. Since we are sending them in order, we
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* just add the AVR at the head of the list.
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* -sorbo.
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*/
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if (!list_empty(&av->av_records)) {
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const struct dccp_ackvec_record *head =
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list_entry(av->av_records.next,
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struct dccp_ackvec_record,
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avr_node);
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BUG_ON(before48(avr->avr_ack_seqno, head->avr_ack_seqno));
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}
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list_add(&avr->avr_node, &av->av_records);
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}
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int dccp_insert_option_ackvec(struct sock *sk, struct sk_buff *skb)
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{
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struct dccp_sock *dp = dccp_sk(sk);
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struct dccp_ackvec *av = dp->dccps_hc_rx_ackvec;
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/* Figure out how many options do we need to represent the ackvec */
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const u8 nr_opts = DIV_ROUND_UP(av->av_vec_len, DCCP_SINGLE_OPT_MAXLEN);
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u16 len = av->av_vec_len + 2 * nr_opts, i;
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u32 elapsed_time;
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const unsigned char *tail, *from;
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unsigned char *to;
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struct dccp_ackvec_record *avr;
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suseconds_t delta;
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if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN)
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return -1;
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delta = ktime_us_delta(ktime_get_real(), av->av_time);
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elapsed_time = delta / 10;
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if (elapsed_time != 0 &&
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dccp_insert_option_elapsed_time(skb, elapsed_time))
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return -1;
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avr = dccp_ackvec_record_new();
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if (avr == NULL)
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return -1;
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DCCP_SKB_CB(skb)->dccpd_opt_len += len;
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to = skb_push(skb, len);
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len = av->av_vec_len;
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from = av->av_buf + av->av_buf_head;
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tail = av->av_buf + DCCP_MAX_ACKVEC_LEN;
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for (i = 0; i < nr_opts; ++i) {
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int copylen = len;
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if (len > DCCP_SINGLE_OPT_MAXLEN)
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copylen = DCCP_SINGLE_OPT_MAXLEN;
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*to++ = DCCPO_ACK_VECTOR_0;
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*to++ = copylen + 2;
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/* Check if buf_head wraps */
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if (from + copylen > tail) {
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const u16 tailsize = tail - from;
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memcpy(to, from, tailsize);
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to += tailsize;
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len -= tailsize;
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copylen -= tailsize;
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from = av->av_buf;
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}
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memcpy(to, from, copylen);
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from += copylen;
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to += copylen;
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len -= copylen;
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}
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/*
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* From RFC 4340, A.2:
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*
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* For each acknowledgement it sends, the HC-Receiver will add an
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* acknowledgement record. ack_seqno will equal the HC-Receiver
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* sequence number it used for the ack packet; ack_ptr will equal
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* buf_head; ack_ackno will equal buf_ackno; and ack_nonce will
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* equal buf_nonce.
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*/
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avr->avr_ack_seqno = DCCP_SKB_CB(skb)->dccpd_seq;
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avr->avr_ack_ptr = av->av_buf_head;
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avr->avr_ack_ackno = av->av_buf_ackno;
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avr->avr_ack_nonce = av->av_buf_nonce;
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avr->avr_sent_len = av->av_vec_len;
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dccp_ackvec_insert_avr(av, avr);
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dccp_pr_debug("%s ACK Vector 0, len=%d, ack_seqno=%llu, "
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"ack_ackno=%llu\n",
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dccp_role(sk), avr->avr_sent_len,
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(unsigned long long)avr->avr_ack_seqno,
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(unsigned long long)avr->avr_ack_ackno);
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return 0;
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}
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struct dccp_ackvec *dccp_ackvec_alloc(const gfp_t priority)
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{
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struct dccp_ackvec *av = kmem_cache_alloc(dccp_ackvec_slab, priority);
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struct dccp_ackvec *av = kmem_cache_zalloc(dccp_ackvec_slab, priority);
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if (av != NULL) {
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av->av_buf_head = DCCP_MAX_ACKVEC_LEN - 1;
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av->av_buf_ackno = UINT48_MAX + 1;
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av->av_buf_nonce = 0;
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av->av_time = ktime_set(0, 0);
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av->av_vec_len = 0;
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av->av_buf_head = av->av_buf_tail = DCCPAV_MAX_ACKVEC_LEN - 1;
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INIT_LIST_HEAD(&av->av_records);
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}
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return av;
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}
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static void dccp_ackvec_purge_records(struct dccp_ackvec *av)
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{
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struct dccp_ackvec_record *cur, *next;
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list_for_each_entry_safe(cur, next, &av->av_records, avr_node)
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kmem_cache_free(dccp_ackvec_record_slab, cur);
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INIT_LIST_HEAD(&av->av_records);
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}
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void dccp_ackvec_free(struct dccp_ackvec *av)
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{
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if (unlikely(av == NULL))
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return;
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|
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if (!list_empty(&av->av_records)) {
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struct dccp_ackvec_record *avr, *next;
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list_for_each_entry_safe(avr, next, &av->av_records, avr_node) {
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list_del_init(&avr->avr_node);
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dccp_ackvec_record_delete(avr);
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}
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}
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if (likely(av != NULL)) {
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dccp_ackvec_purge_records(av);
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kmem_cache_free(dccp_ackvec_slab, av);
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}
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static inline u8 dccp_ackvec_state(const struct dccp_ackvec *av,
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const u32 index)
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{
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return av->av_buf[index] & DCCP_ACKVEC_STATE_MASK;
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}
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static inline u8 dccp_ackvec_len(const struct dccp_ackvec *av,
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const u32 index)
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/**
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* dccp_ackvec_update_records - Record information about sent Ack Vectors
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* @av: Ack Vector records to update
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* @seqno: Sequence number of the packet carrying the Ack Vector just sent
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* @nonce_sum: The sum of all buffer nonces contained in the Ack Vector
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*/
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int dccp_ackvec_update_records(struct dccp_ackvec *av, u64 seqno, u8 nonce_sum)
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{
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return av->av_buf[index] & DCCP_ACKVEC_LEN_MASK;
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struct dccp_ackvec_record *avr;
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avr = kmem_cache_alloc(dccp_ackvec_record_slab, GFP_ATOMIC);
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if (avr == NULL)
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return -ENOBUFS;
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avr->avr_ack_seqno = seqno;
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avr->avr_ack_ptr = av->av_buf_head;
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avr->avr_ack_ackno = av->av_buf_ackno;
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avr->avr_ack_nonce = nonce_sum;
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avr->avr_ack_runlen = dccp_ackvec_runlen(av->av_buf + av->av_buf_head);
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/*
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* When the buffer overflows, we keep no more than one record. This is
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* the simplest way of disambiguating sender-Acks dating from before the
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* overflow from sender-Acks which refer to after the overflow; a simple
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* solution is preferable here since we are handling an exception.
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*/
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if (av->av_overflow)
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dccp_ackvec_purge_records(av);
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/*
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* Since GSS is incremented for each packet, the list is automatically
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* arranged in descending order of @ack_seqno.
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*/
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list_add(&avr->avr_node, &av->av_records);
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dccp_pr_debug("Added Vector, ack_seqno=%llu, ack_ackno=%llu (rl=%u)\n",
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(unsigned long long)avr->avr_ack_seqno,
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(unsigned long long)avr->avr_ack_ackno,
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avr->avr_ack_runlen);
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return 0;
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}
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/*
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* Buffer index and length computation using modulo-buffersize arithmetic.
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* Note that, as pointers move from right to left, head is `before' tail.
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*/
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static inline u16 __ackvec_idx_add(const u16 a, const u16 b)
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{
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return (a + b) % DCCPAV_MAX_ACKVEC_LEN;
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}
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static inline u16 __ackvec_idx_sub(const u16 a, const u16 b)
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{
|
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return __ackvec_idx_add(a, DCCPAV_MAX_ACKVEC_LEN - b);
|
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}
|
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|
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u16 dccp_ackvec_buflen(const struct dccp_ackvec *av)
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{
|
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if (unlikely(av->av_overflow))
|
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return DCCPAV_MAX_ACKVEC_LEN;
|
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return __ackvec_idx_sub(av->av_buf_tail, av->av_buf_head);
|
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}
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|
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/*
|
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|
@ -204,7 +125,7 @@ static inline int dccp_ackvec_set_buf_head_state(struct dccp_ackvec *av,
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long gap;
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long new_head;
|
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|
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if (av->av_vec_len + packets > DCCP_MAX_ACKVEC_LEN)
|
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if (av->av_vec_len + packets > DCCPAV_MAX_ACKVEC_LEN)
|
||||
return -ENOBUFS;
|
||||
|
||||
gap = packets - 1;
|
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|
@ -212,18 +133,18 @@ static inline int dccp_ackvec_set_buf_head_state(struct dccp_ackvec *av,
|
|||
|
||||
if (new_head < 0) {
|
||||
if (gap > 0) {
|
||||
memset(av->av_buf, DCCP_ACKVEC_STATE_NOT_RECEIVED,
|
||||
memset(av->av_buf, DCCPAV_NOT_RECEIVED,
|
||||
gap + new_head + 1);
|
||||
gap = -new_head;
|
||||
}
|
||||
new_head += DCCP_MAX_ACKVEC_LEN;
|
||||
new_head += DCCPAV_MAX_ACKVEC_LEN;
|
||||
}
|
||||
|
||||
av->av_buf_head = new_head;
|
||||
|
||||
if (gap > 0)
|
||||
memset(av->av_buf + av->av_buf_head + 1,
|
||||
DCCP_ACKVEC_STATE_NOT_RECEIVED, gap);
|
||||
DCCPAV_NOT_RECEIVED, gap);
|
||||
|
||||
av->av_buf[av->av_buf_head] = state;
|
||||
av->av_vec_len += packets;
|
||||
|
@ -236,6 +157,8 @@ static inline int dccp_ackvec_set_buf_head_state(struct dccp_ackvec *av,
|
|||
int dccp_ackvec_add(struct dccp_ackvec *av, const struct sock *sk,
|
||||
const u64 ackno, const u8 state)
|
||||
{
|
||||
u8 *cur_head = av->av_buf + av->av_buf_head,
|
||||
*buf_end = av->av_buf + DCCPAV_MAX_ACKVEC_LEN;
|
||||
/*
|
||||
* Check at the right places if the buffer is full, if it is, tell the
|
||||
* caller to start dropping packets till the HC-Sender acks our ACK
|
||||
|
@ -260,7 +183,7 @@ int dccp_ackvec_add(struct dccp_ackvec *av, const struct sock *sk,
|
|||
|
||||
/* See if this is the first ackno being inserted */
|
||||
if (av->av_vec_len == 0) {
|
||||
av->av_buf[av->av_buf_head] = state;
|
||||
*cur_head = state;
|
||||
av->av_vec_len = 1;
|
||||
} else if (after48(ackno, av->av_buf_ackno)) {
|
||||
const u64 delta = dccp_delta_seqno(av->av_buf_ackno, ackno);
|
||||
|
@ -269,10 +192,9 @@ int dccp_ackvec_add(struct dccp_ackvec *av, const struct sock *sk,
|
|||
* Look if the state of this packet is the same as the
|
||||
* previous ackno and if so if we can bump the head len.
|
||||
*/
|
||||
if (delta == 1 &&
|
||||
dccp_ackvec_state(av, av->av_buf_head) == state &&
|
||||
dccp_ackvec_len(av, av->av_buf_head) < DCCP_ACKVEC_LEN_MASK)
|
||||
av->av_buf[av->av_buf_head]++;
|
||||
if (delta == 1 && dccp_ackvec_state(cur_head) == state &&
|
||||
dccp_ackvec_runlen(cur_head) < DCCPAV_MAX_RUNLEN)
|
||||
*cur_head += 1;
|
||||
else if (dccp_ackvec_set_buf_head_state(av, delta, state))
|
||||
return -ENOBUFS;
|
||||
} else {
|
||||
|
@ -285,21 +207,17 @@ int dccp_ackvec_add(struct dccp_ackvec *av, const struct sock *sk,
|
|||
* could reduce the complexity of this scan.)
|
||||
*/
|
||||
u64 delta = dccp_delta_seqno(ackno, av->av_buf_ackno);
|
||||
u32 index = av->av_buf_head;
|
||||
|
||||
while (1) {
|
||||
const u8 len = dccp_ackvec_len(av, index);
|
||||
const u8 av_state = dccp_ackvec_state(av, index);
|
||||
const u8 len = dccp_ackvec_runlen(cur_head);
|
||||
/*
|
||||
* valid packets not yet in av_buf have a reserved
|
||||
* entry, with a len equal to 0.
|
||||
*/
|
||||
if (av_state == DCCP_ACKVEC_STATE_NOT_RECEIVED &&
|
||||
len == 0 && delta == 0) { /* Found our
|
||||
reserved seat! */
|
||||
if (*cur_head == DCCPAV_NOT_RECEIVED && delta == 0) {
|
||||
dccp_pr_debug("Found %llu reserved seat!\n",
|
||||
(unsigned long long)ackno);
|
||||
av->av_buf[index] = state;
|
||||
*cur_head = state;
|
||||
goto out;
|
||||
}
|
||||
/* len == 0 means one packet */
|
||||
|
@ -307,13 +225,12 @@ int dccp_ackvec_add(struct dccp_ackvec *av, const struct sock *sk,
|
|||
goto out_duplicate;
|
||||
|
||||
delta -= len + 1;
|
||||
if (++index == DCCP_MAX_ACKVEC_LEN)
|
||||
index = 0;
|
||||
if (++cur_head == buf_end)
|
||||
cur_head = av->av_buf;
|
||||
}
|
||||
}
|
||||
|
||||
av->av_buf_ackno = ackno;
|
||||
av->av_time = ktime_get_real();
|
||||
out:
|
||||
return 0;
|
||||
|
||||
|
@ -333,13 +250,13 @@ static void dccp_ackvec_throw_record(struct dccp_ackvec *av,
|
|||
if (av->av_buf_head <= avr->avr_ack_ptr)
|
||||
av->av_vec_len = avr->avr_ack_ptr - av->av_buf_head;
|
||||
else
|
||||
av->av_vec_len = DCCP_MAX_ACKVEC_LEN - 1 -
|
||||
av->av_vec_len = DCCPAV_MAX_ACKVEC_LEN - 1 -
|
||||
av->av_buf_head + avr->avr_ack_ptr;
|
||||
|
||||
/* free records */
|
||||
list_for_each_entry_safe_from(avr, next, &av->av_records, avr_node) {
|
||||
list_del_init(&avr->avr_node);
|
||||
dccp_ackvec_record_delete(avr);
|
||||
list_del(&avr->avr_node);
|
||||
kmem_cache_free(dccp_ackvec_record_slab, avr);
|
||||
}
|
||||
}
|
||||
|
||||
|
@ -357,7 +274,7 @@ void dccp_ackvec_check_rcv_ackno(struct dccp_ackvec *av, struct sock *sk,
|
|||
if (ackno == avr->avr_ack_seqno) {
|
||||
dccp_pr_debug("%s ACK packet 0, len=%d, ack_seqno=%llu, "
|
||||
"ack_ackno=%llu, ACKED!\n",
|
||||
dccp_role(sk), 1,
|
||||
dccp_role(sk), avr->avr_ack_runlen,
|
||||
(unsigned long long)avr->avr_ack_seqno,
|
||||
(unsigned long long)avr->avr_ack_ackno);
|
||||
dccp_ackvec_throw_record(av, avr);
|
||||
|
@ -387,7 +304,7 @@ static void dccp_ackvec_check_rcv_ackvector(struct dccp_ackvec *av,
|
|||
*/
|
||||
avr = list_entry(av->av_records.next, struct dccp_ackvec_record, avr_node);
|
||||
while (i--) {
|
||||
const u8 rl = *vector & DCCP_ACKVEC_LEN_MASK;
|
||||
const u8 rl = dccp_ackvec_runlen(vector);
|
||||
u64 ackno_end_rl;
|
||||
|
||||
dccp_set_seqno(&ackno_end_rl, *ackno - rl);
|
||||
|
@ -404,8 +321,7 @@ static void dccp_ackvec_check_rcv_ackvector(struct dccp_ackvec *av,
|
|||
break;
|
||||
found:
|
||||
if (between48(avr->avr_ack_seqno, ackno_end_rl, *ackno)) {
|
||||
const u8 state = *vector & DCCP_ACKVEC_STATE_MASK;
|
||||
if (state != DCCP_ACKVEC_STATE_NOT_RECEIVED) {
|
||||
if (dccp_ackvec_state(vector) != DCCPAV_NOT_RECEIVED) {
|
||||
dccp_pr_debug("%s ACK vector 0, len=%d, "
|
||||
"ack_seqno=%llu, ack_ackno=%llu, "
|
||||
"ACKED!\n",
|
||||
|
@ -448,8 +364,7 @@ int __init dccp_ackvec_init(void)
|
|||
if (dccp_ackvec_slab == NULL)
|
||||
goto out_err;
|
||||
|
||||
dccp_ackvec_record_slab =
|
||||
kmem_cache_create("dccp_ackvec_record",
|
||||
dccp_ackvec_record_slab = kmem_cache_create("dccp_ackvec_record",
|
||||
sizeof(struct dccp_ackvec_record),
|
||||
0, SLAB_HWCACHE_ALIGN, NULL);
|
||||
if (dccp_ackvec_record_slab == NULL)
|
||||
|
|
|
@ -3,9 +3,9 @@
|
|||
/*
|
||||
* net/dccp/ackvec.h
|
||||
*
|
||||
* An implementation of the DCCP protocol
|
||||
* An implementation of Ack Vectors for the DCCP protocol
|
||||
* Copyright (c) 2007 University of Aberdeen, Scotland, UK
|
||||
* Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@mandriva.com>
|
||||
*
|
||||
* This program is free software; you can redistribute it and/or modify it
|
||||
* under the terms of the GNU General Public License version 2 as
|
||||
* published by the Free Software Foundation.
|
||||
|
@ -13,75 +13,89 @@
|
|||
|
||||
#include <linux/dccp.h>
|
||||
#include <linux/compiler.h>
|
||||
#include <linux/ktime.h>
|
||||
#include <linux/list.h>
|
||||
#include <linux/types.h>
|
||||
|
||||
/* We can spread an ack vector across multiple options */
|
||||
#define DCCP_MAX_ACKVEC_LEN (DCCP_SINGLE_OPT_MAXLEN * 2)
|
||||
/*
|
||||
* Ack Vector buffer space is static, in multiples of %DCCP_SINGLE_OPT_MAXLEN,
|
||||
* the maximum size of a single Ack Vector. Setting %DCCPAV_NUM_ACKVECS to 1
|
||||
* will be sufficient for most cases of low Ack Ratios, using a value of 2 gives
|
||||
* more headroom if Ack Ratio is higher or when the sender acknowledges slowly.
|
||||
* The maximum value is bounded by the u16 types for indices and functions.
|
||||
*/
|
||||
#define DCCPAV_NUM_ACKVECS 2
|
||||
#define DCCPAV_MAX_ACKVEC_LEN (DCCP_SINGLE_OPT_MAXLEN * DCCPAV_NUM_ACKVECS)
|
||||
|
||||
/* Estimated minimum average Ack Vector length - used for updating MPS */
|
||||
#define DCCPAV_MIN_OPTLEN 16
|
||||
|
||||
#define DCCP_ACKVEC_STATE_RECEIVED 0
|
||||
#define DCCP_ACKVEC_STATE_ECN_MARKED (1 << 6)
|
||||
#define DCCP_ACKVEC_STATE_NOT_RECEIVED (3 << 6)
|
||||
enum dccp_ackvec_states {
|
||||
DCCPAV_RECEIVED = 0x00,
|
||||
DCCPAV_ECN_MARKED = 0x40,
|
||||
DCCPAV_RESERVED = 0x80,
|
||||
DCCPAV_NOT_RECEIVED = 0xC0
|
||||
};
|
||||
#define DCCPAV_MAX_RUNLEN 0x3F
|
||||
|
||||
#define DCCP_ACKVEC_STATE_MASK 0xC0 /* 11000000 */
|
||||
#define DCCP_ACKVEC_LEN_MASK 0x3F /* 00111111 */
|
||||
static inline u8 dccp_ackvec_runlen(const u8 *cell)
|
||||
{
|
||||
return *cell & DCCPAV_MAX_RUNLEN;
|
||||
}
|
||||
|
||||
/** struct dccp_ackvec - ack vector
|
||||
static inline u8 dccp_ackvec_state(const u8 *cell)
|
||||
{
|
||||
return *cell & ~DCCPAV_MAX_RUNLEN;
|
||||
}
|
||||
|
||||
/** struct dccp_ackvec - Ack Vector main data structure
|
||||
*
|
||||
* This data structure is the one defined in RFC 4340, Appendix A.
|
||||
* This implements a fixed-size circular buffer within an array and is largely
|
||||
* based on Appendix A of RFC 4340.
|
||||
*
|
||||
* @av_buf_head - circular buffer head
|
||||
* @av_buf_tail - circular buffer tail
|
||||
* @av_buf_ackno - ack # of the most recent packet acknowledgeable in the
|
||||
* buffer (i.e. %av_buf_head)
|
||||
* @av_buf_nonce - the one-bit sum of the ECN Nonces on all packets acked
|
||||
* by the buffer with State 0
|
||||
*
|
||||
* Additionally, the HC-Receiver must keep some information about the
|
||||
* Ack Vectors it has recently sent. For each packet sent carrying an
|
||||
* Ack Vector, it remembers four variables:
|
||||
*
|
||||
* @av_records - list of dccp_ackvec_record
|
||||
* @av_ack_nonce - the one-bit sum of the ECN Nonces for all State 0.
|
||||
*
|
||||
* @av_time - the time in usecs
|
||||
* @av_buf - circular buffer of acknowledgeable packets
|
||||
* @av_buf: circular buffer storage area
|
||||
* @av_buf_head: head index; begin of live portion in @av_buf
|
||||
* @av_buf_tail: tail index; first index _after_ the live portion in @av_buf
|
||||
* @av_buf_ackno: highest seqno of acknowledgeable packet recorded in @av_buf
|
||||
* @av_tail_ackno: lowest seqno of acknowledgeable packet recorded in @av_buf
|
||||
* @av_buf_nonce: ECN nonce sums, each covering subsequent segments of up to
|
||||
* %DCCP_SINGLE_OPT_MAXLEN cells in the live portion of @av_buf
|
||||
* @av_overflow: if 1 then buf_head == buf_tail indicates buffer wraparound
|
||||
* @av_records: list of %dccp_ackvec_record (Ack Vectors sent previously)
|
||||
* @av_veclen: length of the live portion of @av_buf
|
||||
*/
|
||||
struct dccp_ackvec {
|
||||
u64 av_buf_ackno;
|
||||
struct list_head av_records;
|
||||
ktime_t av_time;
|
||||
u8 av_buf[DCCPAV_MAX_ACKVEC_LEN];
|
||||
u16 av_buf_head;
|
||||
u16 av_buf_tail;
|
||||
u64 av_buf_ackno:48;
|
||||
u64 av_tail_ackno:48;
|
||||
bool av_buf_nonce[DCCPAV_NUM_ACKVECS];
|
||||
u8 av_overflow:1;
|
||||
struct list_head av_records;
|
||||
u16 av_vec_len;
|
||||
u8 av_buf_nonce;
|
||||
u8 av_ack_nonce;
|
||||
u8 av_buf[DCCP_MAX_ACKVEC_LEN];
|
||||
};
|
||||
|
||||
/** struct dccp_ackvec_record - ack vector record
|
||||
/** struct dccp_ackvec_record - Records information about sent Ack Vectors
|
||||
*
|
||||
* ACK vector record as defined in Appendix A of spec.
|
||||
* These list entries define the additional information which the HC-Receiver
|
||||
* keeps about recently-sent Ack Vectors; again refer to RFC 4340, Appendix A.
|
||||
*
|
||||
* The list is sorted by avr_ack_seqno
|
||||
* @avr_node: the list node in @av_records
|
||||
* @avr_ack_seqno: sequence number of the packet the Ack Vector was sent on
|
||||
* @avr_ack_ackno: the Ack number that this record/Ack Vector refers to
|
||||
* @avr_ack_ptr: pointer into @av_buf where this record starts
|
||||
* @avr_ack_runlen: run length of @avr_ack_ptr at the time of sending
|
||||
* @avr_ack_nonce: the sum of @av_buf_nonce's at the time this record was sent
|
||||
*
|
||||
* @avr_node - node in av_records
|
||||
* @avr_ack_seqno - sequence number of the packet this record was sent on
|
||||
* @avr_ack_ackno - sequence number being acknowledged
|
||||
* @avr_ack_ptr - pointer into av_buf where this record starts
|
||||
* @avr_ack_nonce - av_ack_nonce at the time this record was sent
|
||||
* @avr_sent_len - lenght of the record in av_buf
|
||||
* The list as a whole is sorted in descending order by @avr_ack_seqno.
|
||||
*/
|
||||
struct dccp_ackvec_record {
|
||||
struct list_head avr_node;
|
||||
u64 avr_ack_seqno;
|
||||
u64 avr_ack_ackno;
|
||||
u64 avr_ack_seqno:48;
|
||||
u64 avr_ack_ackno:48;
|
||||
u16 avr_ack_ptr;
|
||||
u16 avr_sent_len;
|
||||
u8 avr_ack_nonce;
|
||||
u8 avr_ack_runlen;
|
||||
u8 avr_ack_nonce:1;
|
||||
};
|
||||
|
||||
struct sock;
|
||||
|
@ -102,10 +116,11 @@ extern int dccp_ackvec_parse(struct sock *sk, const struct sk_buff *skb,
|
|||
u64 *ackno, const u8 opt,
|
||||
const u8 *value, const u8 len);
|
||||
|
||||
extern int dccp_insert_option_ackvec(struct sock *sk, struct sk_buff *skb);
|
||||
extern int dccp_ackvec_update_records(struct dccp_ackvec *av, u64 seq, u8 sum);
|
||||
extern u16 dccp_ackvec_buflen(const struct dccp_ackvec *av);
|
||||
|
||||
static inline int dccp_ackvec_pending(const struct dccp_ackvec *av)
|
||||
static inline bool dccp_ackvec_is_empty(const struct dccp_ackvec *av)
|
||||
{
|
||||
return av->av_vec_len;
|
||||
return av->av_overflow == 0 && av->av_buf_head == av->av_buf_tail;
|
||||
}
|
||||
#endif /* _ACKVEC_H */
|
||||
|
|
|
@ -513,8 +513,7 @@ static void ccid2_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb)
|
|||
&vector, &veclen)) != -1) {
|
||||
/* go through this ack vector */
|
||||
while (veclen--) {
|
||||
const u8 rl = *vector & DCCP_ACKVEC_LEN_MASK;
|
||||
u64 ackno_end_rl = SUB48(ackno, rl);
|
||||
u64 ackno_end_rl = SUB48(ackno, dccp_ackvec_runlen(vector));
|
||||
|
||||
ccid2_pr_debug("ackvec start:%llu end:%llu\n",
|
||||
(unsigned long long)ackno,
|
||||
|
@ -537,17 +536,15 @@ static void ccid2_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb)
|
|||
* run length
|
||||
*/
|
||||
while (between48(seqp->ccid2s_seq,ackno_end_rl,ackno)) {
|
||||
const u8 state = *vector &
|
||||
DCCP_ACKVEC_STATE_MASK;
|
||||
const u8 state = dccp_ackvec_state(vector);
|
||||
|
||||
/* new packet received or marked */
|
||||
if (state != DCCP_ACKVEC_STATE_NOT_RECEIVED &&
|
||||
if (state != DCCPAV_NOT_RECEIVED &&
|
||||
!seqp->ccid2s_acked) {
|
||||
if (state ==
|
||||
DCCP_ACKVEC_STATE_ECN_MARKED) {
|
||||
if (state == DCCPAV_ECN_MARKED)
|
||||
ccid2_congestion_event(sk,
|
||||
seqp);
|
||||
} else
|
||||
else
|
||||
ccid2_new_ack(sk, seqp,
|
||||
&maxincr);
|
||||
|
||||
|
|
|
@ -457,12 +457,15 @@ static inline void dccp_update_gss(struct sock *sk, u64 seq)
|
|||
dp->dccps_awh = dp->dccps_gss;
|
||||
}
|
||||
|
||||
static inline int dccp_ackvec_pending(const struct sock *sk)
|
||||
{
|
||||
return dccp_sk(sk)->dccps_hc_rx_ackvec != NULL &&
|
||||
!dccp_ackvec_is_empty(dccp_sk(sk)->dccps_hc_rx_ackvec);
|
||||
}
|
||||
|
||||
static inline int dccp_ack_pending(const struct sock *sk)
|
||||
{
|
||||
const struct dccp_sock *dp = dccp_sk(sk);
|
||||
return (dp->dccps_hc_rx_ackvec != NULL &&
|
||||
dccp_ackvec_pending(dp->dccps_hc_rx_ackvec)) ||
|
||||
inet_csk_ack_scheduled(sk);
|
||||
return dccp_ackvec_pending(sk) || inet_csk_ack_scheduled(sk);
|
||||
}
|
||||
|
||||
extern int dccp_feat_finalise_settings(struct dccp_sock *dp);
|
||||
|
|
|
@ -378,8 +378,7 @@ int dccp_rcv_established(struct sock *sk, struct sk_buff *skb,
|
|||
|
||||
if (dp->dccps_hc_rx_ackvec != NULL &&
|
||||
dccp_ackvec_add(dp->dccps_hc_rx_ackvec, sk,
|
||||
DCCP_SKB_CB(skb)->dccpd_seq,
|
||||
DCCP_ACKVEC_STATE_RECEIVED))
|
||||
DCCP_SKB_CB(skb)->dccpd_seq, DCCPAV_RECEIVED))
|
||||
goto discard;
|
||||
dccp_deliver_input_to_ccids(sk, skb);
|
||||
|
||||
|
@ -637,8 +636,7 @@ int dccp_rcv_state_process(struct sock *sk, struct sk_buff *skb,
|
|||
|
||||
if (dp->dccps_hc_rx_ackvec != NULL &&
|
||||
dccp_ackvec_add(dp->dccps_hc_rx_ackvec, sk,
|
||||
DCCP_SKB_CB(skb)->dccpd_seq,
|
||||
DCCP_ACKVEC_STATE_RECEIVED))
|
||||
DCCP_SKB_CB(skb)->dccpd_seq, DCCPAV_RECEIVED))
|
||||
goto discard;
|
||||
|
||||
dccp_deliver_input_to_ccids(sk, skb);
|
||||
|
|
|
@ -340,6 +340,7 @@ static inline int dccp_elapsed_time_len(const u32 elapsed_time)
|
|||
return elapsed_time == 0 ? 0 : elapsed_time <= 0xFFFF ? 2 : 4;
|
||||
}
|
||||
|
||||
/* FIXME: This function is currently not used anywhere */
|
||||
int dccp_insert_option_elapsed_time(struct sk_buff *skb, u32 elapsed_time)
|
||||
{
|
||||
const int elapsed_time_len = dccp_elapsed_time_len(elapsed_time);
|
||||
|
@ -424,6 +425,67 @@ static int dccp_insert_option_timestamp_echo(struct dccp_sock *dp,
|
|||
return 0;
|
||||
}
|
||||
|
||||
static int dccp_insert_option_ackvec(struct sock *sk, struct sk_buff *skb)
|
||||
{
|
||||
struct dccp_sock *dp = dccp_sk(sk);
|
||||
struct dccp_ackvec *av = dp->dccps_hc_rx_ackvec;
|
||||
const u16 buflen = dccp_ackvec_buflen(av);
|
||||
/* Figure out how many options do we need to represent the ackvec */
|
||||
const u8 nr_opts = DIV_ROUND_UP(buflen, DCCP_SINGLE_OPT_MAXLEN);
|
||||
u16 len = buflen + 2 * nr_opts;
|
||||
u8 i, nonce = 0;
|
||||
const unsigned char *tail, *from;
|
||||
unsigned char *to;
|
||||
|
||||
if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN)
|
||||
return -1;
|
||||
|
||||
DCCP_SKB_CB(skb)->dccpd_opt_len += len;
|
||||
|
||||
to = skb_push(skb, len);
|
||||
len = buflen;
|
||||
from = av->av_buf + av->av_buf_head;
|
||||
tail = av->av_buf + DCCPAV_MAX_ACKVEC_LEN;
|
||||
|
||||
for (i = 0; i < nr_opts; ++i) {
|
||||
int copylen = len;
|
||||
|
||||
if (len > DCCP_SINGLE_OPT_MAXLEN)
|
||||
copylen = DCCP_SINGLE_OPT_MAXLEN;
|
||||
|
||||
/*
|
||||
* RFC 4340, 12.2: Encode the Nonce Echo for this Ack Vector via
|
||||
* its type; ack_nonce is the sum of all individual buf_nonce's.
|
||||
*/
|
||||
nonce ^= av->av_buf_nonce[i];
|
||||
|
||||
*to++ = DCCPO_ACK_VECTOR_0 + av->av_buf_nonce[i];
|
||||
*to++ = copylen + 2;
|
||||
|
||||
/* Check if buf_head wraps */
|
||||
if (from + copylen > tail) {
|
||||
const u16 tailsize = tail - from;
|
||||
|
||||
memcpy(to, from, tailsize);
|
||||
to += tailsize;
|
||||
len -= tailsize;
|
||||
copylen -= tailsize;
|
||||
from = av->av_buf;
|
||||
}
|
||||
|
||||
memcpy(to, from, copylen);
|
||||
from += copylen;
|
||||
to += copylen;
|
||||
len -= copylen;
|
||||
}
|
||||
/*
|
||||
* Each sent Ack Vector is recorded in the list, as per A.2 of RFC 4340.
|
||||
*/
|
||||
if (dccp_ackvec_update_records(av, DCCP_SKB_CB(skb)->dccpd_seq, nonce))
|
||||
return -ENOBUFS;
|
||||
return 0;
|
||||
}
|
||||
|
||||
/**
|
||||
* dccp_insert_option_mandatory - Mandatory option (5.8.2)
|
||||
* Note that since we are using skb_push, this function needs to be called
|
||||
|
@ -519,8 +581,7 @@ int dccp_insert_options(struct sock *sk, struct sk_buff *skb)
|
|||
if (dccp_insert_option_timestamp(skb))
|
||||
return -1;
|
||||
|
||||
} else if (dp->dccps_hc_rx_ackvec != NULL &&
|
||||
dccp_ackvec_pending(dp->dccps_hc_rx_ackvec) &&
|
||||
} else if (dccp_ackvec_pending(sk) &&
|
||||
dccp_insert_option_ackvec(sk, skb)) {
|
||||
return -1;
|
||||
}
|
||||
|
|
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