#include "dccp.h"
#include <linux/dccp.h>
+#include <linux/init.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
#include <linux/skbuff.h>
+#include <linux/slab.h>
#include <net/sock.h>
+static struct kmem_cache *dccp_ackvec_slab;
+static struct kmem_cache *dccp_ackvec_record_slab;
+
+static struct dccp_ackvec_record *dccp_ackvec_record_new(void)
+{
+ struct dccp_ackvec_record *avr =
+ kmem_cache_alloc(dccp_ackvec_record_slab, GFP_ATOMIC);
+
+ if (avr != NULL)
+ INIT_LIST_HEAD(&avr->dccpavr_node);
+
+ return avr;
+}
+
+static void dccp_ackvec_record_delete(struct dccp_ackvec_record *avr)
+{
+ if (unlikely(avr == NULL))
+ return;
+ /* Check if deleting a linked record */
+ WARN_ON(!list_empty(&avr->dccpavr_node));
+ kmem_cache_free(dccp_ackvec_record_slab, avr);
+}
+
+static void dccp_ackvec_insert_avr(struct dccp_ackvec *av,
+ struct dccp_ackvec_record *avr)
+{
+ /*
+ * AVRs are sorted by seqno. Since we are sending them in order, we
+ * just add the AVR at the head of the list.
+ * -sorbo.
+ */
+ if (!list_empty(&av->dccpav_records)) {
+ const struct dccp_ackvec_record *head =
+ list_entry(av->dccpav_records.next,
+ struct dccp_ackvec_record,
+ dccpavr_node);
+ BUG_ON(before48(avr->dccpavr_ack_seqno,
+ head->dccpavr_ack_seqno));
+ }
+
+ list_add(&avr->dccpavr_node, &av->dccpav_records);
+}
+
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;
- int len = av->dccpav_vec_len + 2;
+ /* Figure out how many options do we need to represent the ackvec */
+ const u16 nr_opts = (av->dccpav_vec_len +
+ DCCP_MAX_ACKVEC_OPT_LEN - 1) /
+ DCCP_MAX_ACKVEC_OPT_LEN;
+ u16 len = av->dccpav_vec_len + 2 * nr_opts, i;
struct timeval now;
u32 elapsed_time;
- unsigned char *to, *from;
+ const unsigned char *tail, *from;
+ unsigned char *to;
+ struct dccp_ackvec_record *avr;
+
+ if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN)
+ return -1;
dccp_timestamp(sk, &now);
elapsed_time = timeval_delta(&now, &av->dccpav_time) / 10;
- if (elapsed_time != 0)
- dccp_insert_option_elapsed_time(sk, skb, elapsed_time);
-
- if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN)
+ if (elapsed_time != 0 &&
+ dccp_insert_option_elapsed_time(sk, skb, elapsed_time))
return -1;
- /*
- * XXX: now we have just one ack vector sent record, so
- * we have to wait for it to be cleared.
- *
- * Of course this is not acceptable, but this is just for
- * basic testing now.
- */
- if (av->dccpav_ack_seqno != DCCP_MAX_SEQNO + 1)
+ avr = dccp_ackvec_record_new();
+ if (avr == NULL)
return -1;
DCCP_SKB_CB(skb)->dccpd_opt_len += len;
- to = skb_push(skb, len);
- *to++ = DCCPO_ACK_VECTOR_0;
- *to++ = len;
-
+ to = skb_push(skb, len);
len = av->dccpav_vec_len;
from = av->dccpav_buf + av->dccpav_buf_head;
+ tail = av->dccpav_buf + DCCP_MAX_ACKVEC_LEN;
+
+ for (i = 0; i < nr_opts; ++i) {
+ int copylen = len;
+
+ if (len > DCCP_MAX_ACKVEC_OPT_LEN)
+ copylen = DCCP_MAX_ACKVEC_OPT_LEN;
+
+ *to++ = DCCPO_ACK_VECTOR_0;
+ *to++ = copylen + 2;
+
+ /* Check if buf_head wraps */
+ if (from + copylen > tail) {
+ const u16 tailsize = tail - from;
- /* Check if buf_head wraps */
- if ((int)av->dccpav_buf_head + len > av->dccpav_vec_len) {
- const u32 tailsize = av->dccpav_vec_len - av->dccpav_buf_head;
+ memcpy(to, from, tailsize);
+ to += tailsize;
+ len -= tailsize;
+ copylen -= tailsize;
+ from = av->dccpav_buf;
+ }
- memcpy(to, from, tailsize);
- to += tailsize;
- len -= tailsize;
- from = av->dccpav_buf;
+ memcpy(to, from, copylen);
+ from += copylen;
+ to += copylen;
+ len -= copylen;
}
- 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
* 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.
- *
- * This implemention uses just one ack record for now.
*/
- av->dccpav_ack_seqno = DCCP_SKB_CB(skb)->dccpd_seq;
- av->dccpav_ack_ptr = av->dccpav_buf_head;
- av->dccpav_ack_ackno = av->dccpav_buf_ackno;
- av->dccpav_ack_nonce = av->dccpav_buf_nonce;
- av->dccpav_sent_len = av->dccpav_vec_len;
+ avr->dccpavr_ack_seqno = DCCP_SKB_CB(skb)->dccpd_seq;
+ avr->dccpavr_ack_ptr = av->dccpav_buf_head;
+ avr->dccpavr_ack_ackno = av->dccpav_buf_ackno;
+ avr->dccpavr_ack_nonce = av->dccpav_buf_nonce;
+ avr->dccpavr_sent_len = av->dccpav_vec_len;
+
+ 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, av->dccpav_sent_len,
- (unsigned long long)av->dccpav_ack_seqno,
- (unsigned long long)av->dccpav_ack_ackno);
- return -1;
+ dccp_role(sk), avr->dccpavr_sent_len,
+ (unsigned long long)avr->dccpavr_ack_seqno,
+ (unsigned long long)avr->dccpavr_ack_ackno);
+ return 0;
}
-struct dccp_ackvec *dccp_ackvec_alloc(const unsigned int len,
- const gfp_t priority)
+struct dccp_ackvec *dccp_ackvec_alloc(const gfp_t priority)
{
- struct dccp_ackvec *av;
-
- BUG_ON(len == 0);
+ struct dccp_ackvec *av = kmem_cache_alloc(dccp_ackvec_slab, priority);
- if (len > DCCP_MAX_ACKVEC_LEN)
- return NULL;
-
- av = kmalloc(sizeof(*av) + len, priority);
if (av != NULL) {
- av->dccpav_buf_len = len;
- av->dccpav_buf_head =
- av->dccpav_buf_tail = av->dccpav_buf_len - 1;
- av->dccpav_buf_ackno =
- av->dccpav_ack_ackno = av->dccpav_ack_seqno = ~0LLU;
+ 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);
}
return av;
void dccp_ackvec_free(struct dccp_ackvec *av)
{
- kfree(av);
+ if (unlikely(av == NULL))
+ return;
+
+ if (!list_empty(&av->dccpav_records)) {
+ struct dccp_ackvec_record *avr, *next;
+
+ list_for_each_entry_safe(avr, next, &av->dccpav_records,
+ dccpavr_node) {
+ list_del_init(&avr->dccpavr_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 u8 index)
+ const u32 index)
{
return av->dccpav_buf[index] & DCCP_ACKVEC_STATE_MASK;
}
static inline u8 dccp_ackvec_len(const struct dccp_ackvec *av,
- const u8 index)
+ const u32 index)
{
return av->dccpav_buf[index] & DCCP_ACKVEC_LEN_MASK;
}
unsigned int gap;
long new_head;
- if (av->dccpav_vec_len + packets > av->dccpav_buf_len)
+ if (av->dccpav_vec_len + packets > DCCP_MAX_ACKVEC_LEN)
return -ENOBUFS;
gap = packets - 1;
gap + new_head + 1);
gap = -new_head;
}
- new_head += av->dccpav_buf_len;
- }
+ new_head += DCCP_MAX_ACKVEC_LEN;
+ }
av->dccpav_buf_head = new_head;
}
/*
- * 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)
* 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
/*
* 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);
- u8 index = av->dccpav_buf_head;
+ u32 index = av->dccpav_buf_head;
while (1) {
const u8 len = dccp_ackvec_len(av, index);
goto out_duplicate;
delta -= len + 1;
- if (++index == av->dccpav_buf_len)
+ if (++index == DCCP_MAX_ACKVEC_LEN)
index = 0;
}
}
av->dccpav_buf_ackno = ackno;
dccp_timestamp(sk, &av->dccpav_time);
out:
- dccp_pr_debug("");
return 0;
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)
}
#endif
-static void dccp_ackvec_throw_away_ack_record(struct dccp_ackvec *av)
+static void dccp_ackvec_throw_record(struct dccp_ackvec *av,
+ struct dccp_ackvec_record *avr)
{
- /*
- * As we're keeping track of the ack vector size (dccpav_vec_len) and
- * the sent ack vector size (dccpav_sent_len) we don't need
- * dccpav_buf_tail at all, but keep this code here as in the future
- * we'll implement a vector of ack records, as suggested in
- * draft-ietf-dccp-spec-11.txt Appendix A. -acme
- */
-#if 0
- u32 new_buf_tail = av->dccpav_ack_ptr + 1;
- if (new_buf_tail >= av->dccpav_vec_len)
- new_buf_tail -= av->dccpav_vec_len;
- av->dccpav_buf_tail = new_buf_tail;
-#endif
- av->dccpav_vec_len -= av->dccpav_sent_len;
+ struct dccp_ackvec_record *next;
+
+ /* 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,
+ dccpavr_node) {
+ list_del_init(&avr->dccpavr_node);
+ dccp_ackvec_record_delete(avr);
+ }
}
void dccp_ackvec_check_rcv_ackno(struct dccp_ackvec *av, struct sock *sk,
const u64 ackno)
{
- /* Check if we actually sent an ACK vector */
- if (av->dccpav_ack_seqno == DCCP_MAX_SEQNO + 1)
- return;
+ struct dccp_ackvec_record *avr;
- if (ackno == av->dccpav_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, "
- "ack_ackno=%llu, ACKED!\n",
- debug_prefix, 1,
- (unsigned long long)av->dccpav_ack_seqno,
- (unsigned long long)av->dccpav_ack_ackno);
- dccp_ackvec_throw_away_ack_record(av);
- av->dccpav_ack_seqno = DCCP_MAX_SEQNO + 1;
+ /*
+ * If we traverse backwards, it should be faster when we have large
+ * windows. We will be receiving ACKs for stuff we sent a while back
+ * -sorbo.
+ */
+ list_for_each_entry_reverse(avr, &av->dccpav_records, dccpavr_node) {
+ if (ackno == avr->dccpavr_ack_seqno) {
+ dccp_pr_debug("%s ACK packet 0, len=%d, ack_seqno=%llu, "
+ "ack_ackno=%llu, ACKED!\n",
+ 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 */
}
}
static void dccp_ackvec_check_rcv_ackvector(struct dccp_ackvec *av,
- struct sock *sk, u64 ackno,
+ struct sock *sk, u64 *ackno,
const unsigned char len,
const unsigned char *vector)
{
unsigned char i;
+ struct dccp_ackvec_record *avr;
/* Check if we actually sent an ACK vector */
- if (av->dccpav_ack_seqno == DCCP_MAX_SEQNO + 1)
- return;
- /*
- * We're in the receiver half connection, so if the received an ACK
- * vector ackno (e.g. 50) before dccpav_ack_seqno (e.g. 52), we're
- * not interested.
- *
- * Extra explanation with example:
- *
- * if we received an ACK vector with ackno 50, it can only be acking
- * 50, 49, 48, etc, not 52 (the seqno for the ACK vector we sent).
- */
- /* dccp_pr_debug("is %llu < %llu? ", ackno, av->dccpav_ack_seqno); */
- if (before48(ackno, av->dccpav_ack_seqno)) {
- /* dccp_pr_debug_cat("yes\n"); */
+ if (list_empty(&av->dccpav_records))
return;
- }
- /* dccp_pr_debug_cat("no\n"); */
i = len;
+ /*
+ * XXX
+ * I think it might be more efficient to work backwards. See comment on
+ * rcv_ackno. -sorbo.
+ */
+ avr = list_entry(av->dccpav_records.next, struct dccp_ackvec_record,
+ dccpavr_node);
while (i--) {
const u8 rl = *vector & DCCP_ACKVEC_LEN_MASK;
u64 ackno_end_rl;
- dccp_set_seqno(&ackno_end_rl, ackno - rl);
+ dccp_set_seqno(&ackno_end_rl, *ackno - rl);
/*
- * dccp_pr_debug("is %llu <= %llu <= %llu? ", ackno_end_rl,
- * av->dccpav_ack_seqno, ackno);
+ * If our AVR sequence number is greater than the ack, go
+ * forward in the AVR list until it is not so.
*/
- if (between48(av->dccpav_ack_seqno, ackno_end_rl, ackno)) {
- const u8 state = (*vector &
- DCCP_ACKVEC_STATE_MASK) >> 6;
- /* dccp_pr_debug_cat("yes\n"); */
-
+ list_for_each_entry_from(avr, &av->dccpav_records,
+ dccpavr_node) {
+ if (!after48(avr->dccpavr_ack_seqno, *ackno))
+ goto found;
+ }
+ /* End of the dccpav_records list, not found, exit */
+ break;
+found:
+ if (between48(avr->dccpavr_ack_seqno, ackno_end_rl, *ackno)) {
+ 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)
- av->dccpav_ack_seqno,
+ avr->dccpavr_ack_seqno,
(unsigned long long)
- av->dccpav_ack_ackno);
- dccp_ackvec_throw_away_ack_record(av);
+ avr->dccpavr_ack_ackno);
+ dccp_ackvec_throw_record(av, avr);
+ break;
}
/*
- * If dccpav_ack_seqno was not received, no problem
- * we'll send another ACK vector.
+ * If it wasn't received, continue scanning... we might
+ * find another one.
*/
- av->dccpav_ack_seqno = DCCP_MAX_SEQNO + 1;
- break;
}
- /* dccp_pr_debug_cat("no\n"); */
- dccp_set_seqno(&ackno, ackno_end_rl - 1);
+ dccp_set_seqno(ackno, ackno_end_rl - 1);
++vector;
}
}
int dccp_ackvec_parse(struct sock *sk, const struct sk_buff *skb,
- const u8 opt, const u8 *value, const u8 len)
+ u64 *ackno, const u8 opt, const u8 *value, const u8 len)
{
- if (len > DCCP_MAX_ACKVEC_LEN)
+ if (len > DCCP_MAX_ACKVEC_OPT_LEN)
return -1;
/* dccp_ackvector_print(DCCP_SKB_CB(skb)->dccpd_ack_seq, value, len); */
dccp_ackvec_check_rcv_ackvector(dccp_sk(sk)->dccps_hc_rx_ackvec, sk,
- DCCP_SKB_CB(skb)->dccpd_ack_seq,
- len, value);
+ ackno, len, value);
return 0;
}
+
+int __init dccp_ackvec_init(void)
+{
+ dccp_ackvec_slab = kmem_cache_create("dccp_ackvec",
+ sizeof(struct dccp_ackvec), 0,
+ SLAB_HWCACHE_ALIGN, NULL, NULL);
+ 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, NULL);
+ if (dccp_ackvec_record_slab == NULL)
+ goto out_destroy_slab;
+
+ return 0;
+
+out_destroy_slab:
+ kmem_cache_destroy(dccp_ackvec_slab);
+ dccp_ackvec_slab = NULL;
+out_err:
+ DCCP_CRIT("Unable to create Ack Vector slab cache");
+ return -ENOBUFS;
+}
+
+void dccp_ackvec_exit(void)
+{
+ if (dccp_ackvec_slab != NULL) {
+ kmem_cache_destroy(dccp_ackvec_slab);
+ dccp_ackvec_slab = NULL;
+ }
+ if (dccp_ackvec_record_slab != NULL) {
+ kmem_cache_destroy(dccp_ackvec_record_slab);
+ dccp_ackvec_record_slab = NULL;
+ }
+}
git://git.onelab.eu / linux-2.6.git / blobdiff