/*
* net/dccp/ackvec.c
*
- * An implementation of Ack Vectors for the DCCP protocol
- * Copyright (c) 2007 University of Aberdeen, Scotland, UK
+ * An implementation of the DCCP protocol
* Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
*
* This program is free software; you can redistribute it and/or modify it
static struct kmem_cache *dccp_ackvec_slab;
static struct kmem_cache *dccp_ackvec_record_slab;
-struct dccp_ackvec *dccp_ackvec_alloc(const gfp_t priority)
+static struct dccp_ackvec_record *dccp_ackvec_record_new(void)
{
- struct dccp_ackvec *av = kmem_cache_zalloc(dccp_ackvec_slab, priority);
-
- if (av != NULL) {
- av->av_buf_head = DCCPAV_MAX_ACKVEC_LEN - 1;
- INIT_LIST_HEAD(&av->av_records);
- }
- return av;
-}
+ struct dccp_ackvec_record *avr =
+ kmem_cache_alloc(dccp_ackvec_record_slab, GFP_ATOMIC);
-static void dccp_ackvec_purge_records(struct dccp_ackvec *av)
-{
- struct dccp_ackvec_record *cur, *next;
+ if (avr != NULL)
+ INIT_LIST_HEAD(&avr->avr_node);
- list_for_each_entry_safe(cur, next, &av->av_records, avr_node)
- kmem_cache_free(dccp_ackvec_record_slab, cur);
- INIT_LIST_HEAD(&av->av_records);
+ return avr;
}
-void dccp_ackvec_free(struct dccp_ackvec *av)
+static void dccp_ackvec_record_delete(struct dccp_ackvec_record *avr)
{
- if (likely(av != NULL)) {
- dccp_ackvec_purge_records(av);
- kmem_cache_free(dccp_ackvec_slab, av);
- }
+ if (unlikely(avr == NULL))
+ return;
+ /* Check if deleting a linked record */
+ WARN_ON(!list_empty(&avr->avr_node));
+ kmem_cache_free(dccp_ackvec_record_slab, avr);
}
static void dccp_ackvec_insert_avr(struct dccp_ackvec *av,
struct dccp_ackvec *av = dp->dccps_hc_rx_ackvec;
/* Figure out how many options do we need to represent the ackvec */
const u8 nr_opts = DIV_ROUND_UP(av->av_vec_len, DCCP_SINGLE_OPT_MAXLEN);
- u16 len = av->av_vec_len + 2 * nr_opts;
- u8 i, nonce = 0;
+ u16 len = av->av_vec_len + 2 * nr_opts, i;
+ u32 elapsed_time;
const unsigned char *tail, *from;
unsigned char *to;
struct dccp_ackvec_record *avr;
+ suseconds_t delta;
if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN)
return -1;
- avr = kmem_cache_alloc(dccp_ackvec_record_slab, GFP_ATOMIC);
+ delta = ktime_us_delta(ktime_get_real(), av->av_time);
+ elapsed_time = delta / 10;
+
+ if (elapsed_time != 0 &&
+ dccp_insert_option_elapsed_time(sk, skb, elapsed_time))
+ return -1;
+
+ avr = dccp_ackvec_record_new();
if (avr == NULL)
return -1;
to = skb_push(skb, len);
len = av->av_vec_len;
from = av->av_buf + av->av_buf_head;
- tail = av->av_buf + DCCPAV_MAX_ACKVEC_LEN;
+ tail = av->av_buf + DCCP_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++ = DCCPO_ACK_VECTOR_0;
*to++ = copylen + 2;
/* Check if buf_head wraps */
}
/*
- * Each sent Ack Vector is recorded in the list, as per A.2 of RFC 4340.
+ * 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
+ * sequence number it used for the ack packet; ack_ptr will equal
+ * buf_head; ack_ackno will equal buf_ackno; and ack_nonce will
+ * equal buf_nonce.
*/
- avr->avr_ack_seqno = DCCP_SKB_CB(skb)->dccpd_seq;
- avr->avr_ack_ptr = av->av_buf_head;
- avr->avr_ack_ackno = av->av_buf_ackno;
- avr->avr_ack_nonce = nonce;
- avr->avr_ack_runlen = dccp_ackvec_runlen(av->av_buf + av->av_buf_head);
+ avr->avr_ack_seqno = DCCP_SKB_CB(skb)->dccpd_seq;
+ avr->avr_ack_ptr = av->av_buf_head;
+ avr->avr_ack_ackno = av->av_buf_ackno;
+ avr->avr_ack_nonce = av->av_buf_nonce;
+ avr->avr_sent_len = av->av_vec_len;
dccp_ackvec_insert_avr(av, avr);
dccp_pr_debug("%s ACK Vector 0, len=%d, ack_seqno=%llu, "
"ack_ackno=%llu\n",
- dccp_role(sk), avr->avr_ack_runlen,
+ dccp_role(sk), avr->avr_sent_len,
(unsigned long long)avr->avr_ack_seqno,
(unsigned long long)avr->avr_ack_ackno);
return 0;
}
+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->av_buf_head = DCCP_MAX_ACKVEC_LEN - 1;
+ av->av_buf_ackno = UINT48_MAX + 1;
+ av->av_buf_nonce = 0;
+ av->av_time = ktime_set(0, 0);
+ av->av_vec_len = 0;
+ INIT_LIST_HEAD(&av->av_records);
+ }
+
+ return av;
+}
+
+void dccp_ackvec_free(struct dccp_ackvec *av)
+{
+ if (unlikely(av == NULL))
+ return;
+
+ if (!list_empty(&av->av_records)) {
+ struct dccp_ackvec_record *avr, *next;
+
+ list_for_each_entry_safe(avr, next, &av->av_records, avr_node) {
+ list_del_init(&avr->avr_node);
+ dccp_ackvec_record_delete(avr);
+ }
+ }
+
+ kmem_cache_free(dccp_ackvec_slab, av);
+}
+
+static inline u8 dccp_ackvec_state(const struct dccp_ackvec *av,
+ const u32 index)
+{
+ return av->av_buf[index] & DCCP_ACKVEC_STATE_MASK;
+}
+
+static inline u8 dccp_ackvec_len(const struct dccp_ackvec *av,
+ const u32 index)
+{
+ return av->av_buf[index] & DCCP_ACKVEC_LEN_MASK;
+}
+
/*
* If several packets are missing, the HC-Receiver may prefer to enter multiple
* bytes with run length 0, rather than a single byte with a larger run length;
unsigned int gap;
long new_head;
- if (av->av_vec_len + packets > DCCPAV_MAX_ACKVEC_LEN)
+ if (av->av_vec_len + packets > DCCP_MAX_ACKVEC_LEN)
return -ENOBUFS;
gap = packets - 1;
if (new_head < 0) {
if (gap > 0) {
- memset(av->av_buf, DCCPAV_NOT_RECEIVED,
+ memset(av->av_buf, DCCP_ACKVEC_STATE_NOT_RECEIVED,
gap + new_head + 1);
gap = -new_head;
}
- new_head += DCCPAV_MAX_ACKVEC_LEN;
+ new_head += DCCP_MAX_ACKVEC_LEN;
}
av->av_buf_head = new_head;
if (gap > 0)
memset(av->av_buf + av->av_buf_head + 1,
- DCCPAV_NOT_RECEIVED, gap);
+ DCCP_ACKVEC_STATE_NOT_RECEIVED, gap);
av->av_buf[av->av_buf_head] = state;
av->av_vec_len += packets;
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
/* See if this is the first ackno being inserted */
if (av->av_vec_len == 0) {
- *cur_head = state;
+ av->av_buf[av->av_buf_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);
* 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(cur_head) == state &&
- dccp_ackvec_runlen(cur_head) < DCCPAV_MAX_RUNLEN)
- *cur_head += 1;
+ 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]++;
else if (dccp_ackvec_set_buf_head_state(av, delta, state))
return -ENOBUFS;
} else {
* 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_runlen(cur_head);
+ const u8 len = dccp_ackvec_len(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 (*cur_head == DCCPAV_NOT_RECEIVED && delta == 0) {
+ if (av_state == DCCP_ACKVEC_STATE_NOT_RECEIVED &&
+ len == 0 && delta == 0) { /* Found our
+ reserved seat! */
dccp_pr_debug("Found %llu reserved seat!\n",
(unsigned long long)ackno);
- *cur_head = state;
+ av->av_buf[index] = state;
goto out;
}
/* len == 0 means one packet */
goto out_duplicate;
delta -= len + 1;
- if (++cur_head == buf_end)
- cur_head = av->av_buf;
+ if (++index == DCCP_MAX_ACKVEC_LEN)
+ index = 0;
}
}
av->av_buf_ackno = ackno;
+ av->av_time = ktime_get_real();
out:
return 0;
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 = DCCPAV_MAX_ACKVEC_LEN - 1 -
+ av->av_vec_len = DCCP_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(&avr->avr_node);
- kmem_cache_free(dccp_ackvec_record_slab, avr);
+ list_del_init(&avr->avr_node);
+ dccp_ackvec_record_delete(avr);
}
}
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), avr->avr_ack_runlen,
+ dccp_role(sk), 1,
(unsigned long long)avr->avr_ack_seqno,
(unsigned long long)avr->avr_ack_ackno);
dccp_ackvec_throw_record(av, avr);
*/
avr = list_entry(av->av_records.next, struct dccp_ackvec_record, avr_node);
while (i--) {
- const u8 rl = dccp_ackvec_runlen(vector);
+ const u8 rl = *vector & DCCP_ACKVEC_LEN_MASK;
u64 ackno_end_rl;
dccp_set_seqno(&ackno_end_rl, *ackno - rl);
break;
found:
if (between48(avr->avr_ack_seqno, ackno_end_rl, *ackno)) {
- if (dccp_ackvec_state(vector) != DCCPAV_NOT_RECEIVED) {
+ const u8 state = *vector & DCCP_ACKVEC_STATE_MASK;
+ if (state != DCCP_ACKVEC_STATE_NOT_RECEIVED) {
dccp_pr_debug("%s ACK vector 0, len=%d, "
"ack_seqno=%llu, ack_ackno=%llu, "
"ACKED!\n",
if (dccp_ackvec_slab == NULL)
goto out_err;
- dccp_ackvec_record_slab = kmem_cache_create("dccp_ackvec_record",
- sizeof(struct dccp_ackvec_record),
- 0, SLAB_HWCACHE_ALIGN, NULL);
+ 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)
goto out_destroy_slab;
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff