/*
- * net/dccp/packet_history.h
+ * net/dccp/packet_history.c
*
- * Copyright (c) 2005 The University of Waikato, Hamilton, New Zealand.
+ * Copyright (c) 2005-6 The University of Waikato, Hamilton, New Zealand.
*
* An implementation of the DCCP protocol
*
* This code has been developed by the University of Waikato WAND
* research group. For further information please see http://www.wand.net.nz/
- * or e-mail Ian McDonald - iam4@cs.waikato.ac.nz
+ * or e-mail Ian McDonald - ian.mcdonald@jandi.co.nz
*
* This code also uses code from Lulea University, rereleased as GPL by its
* authors:
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
-#include <linux/config.h>
#include <linux/module.h>
#include <linux/string.h>
-
#include "packet_history.h"
+/*
+ * Transmitter History Routines
+ */
+struct dccp_tx_hist *dccp_tx_hist_new(const char *name)
+{
+ struct dccp_tx_hist *hist = kmalloc(sizeof(*hist), GFP_ATOMIC);
+ static const char dccp_tx_hist_mask[] = "tx_hist_%s";
+ char *slab_name;
+
+ if (hist == NULL)
+ goto out;
+
+ slab_name = kmalloc(strlen(name) + sizeof(dccp_tx_hist_mask) - 1,
+ GFP_ATOMIC);
+ if (slab_name == NULL)
+ goto out_free_hist;
+
+ sprintf(slab_name, dccp_tx_hist_mask, name);
+ hist->dccptxh_slab = kmem_cache_create(slab_name,
+ sizeof(struct dccp_tx_hist_entry),
+ 0, SLAB_HWCACHE_ALIGN,
+ NULL, NULL);
+ if (hist->dccptxh_slab == NULL)
+ goto out_free_slab_name;
+out:
+ return hist;
+out_free_slab_name:
+ kfree(slab_name);
+out_free_hist:
+ kfree(hist);
+ hist = NULL;
+ goto out;
+}
+
+EXPORT_SYMBOL_GPL(dccp_tx_hist_new);
+
+void dccp_tx_hist_delete(struct dccp_tx_hist *hist)
+{
+ const char* name = kmem_cache_name(hist->dccptxh_slab);
+
+ kmem_cache_destroy(hist->dccptxh_slab);
+ kfree(name);
+ kfree(hist);
+}
+
+EXPORT_SYMBOL_GPL(dccp_tx_hist_delete);
+
+struct dccp_tx_hist_entry *
+ dccp_tx_hist_find_entry(const struct list_head *list, const u64 seq)
+{
+ struct dccp_tx_hist_entry *packet = NULL, *entry;
+
+ list_for_each_entry(entry, list, dccphtx_node)
+ if (entry->dccphtx_seqno == seq) {
+ packet = entry;
+ break;
+ }
+
+ return packet;
+}
+
+EXPORT_SYMBOL_GPL(dccp_tx_hist_find_entry);
+
+void dccp_tx_hist_purge(struct dccp_tx_hist *hist, struct list_head *list)
+{
+ struct dccp_tx_hist_entry *entry, *next;
+
+ list_for_each_entry_safe(entry, next, list, dccphtx_node) {
+ list_del_init(&entry->dccphtx_node);
+ dccp_tx_hist_entry_delete(hist, entry);
+ }
+}
+
+EXPORT_SYMBOL_GPL(dccp_tx_hist_purge);
+
+void dccp_tx_hist_purge_older(struct dccp_tx_hist *hist,
+ struct list_head *list,
+ struct dccp_tx_hist_entry *packet)
+{
+ struct dccp_tx_hist_entry *next;
+
+ list_for_each_entry_safe_continue(packet, next, list, dccphtx_node) {
+ list_del_init(&packet->dccphtx_node);
+ dccp_tx_hist_entry_delete(hist, packet);
+ }
+}
+
+EXPORT_SYMBOL_GPL(dccp_tx_hist_purge_older);
+
+/*
+ * Receiver History Routines
+ */
struct dccp_rx_hist *dccp_rx_hist_new(const char *name)
{
struct dccp_rx_hist *hist = kmalloc(sizeof(*hist), GFP_ATOMIC);
EXPORT_SYMBOL_GPL(dccp_rx_hist_delete);
-void dccp_rx_hist_purge(struct dccp_rx_hist *hist, struct list_head *list)
+int dccp_rx_hist_find_entry(const struct list_head *list, const u64 seq,
+ u8 *ccval)
{
- struct dccp_rx_hist_entry *entry, *next;
+ struct dccp_rx_hist_entry *packet = NULL, *entry;
- list_for_each_entry_safe(entry, next, list, dccphrx_node) {
- list_del_init(&entry->dccphrx_node);
- kmem_cache_free(hist->dccprxh_slab, entry);
- }
-}
+ list_for_each_entry(entry, list, dccphrx_node)
+ if (entry->dccphrx_seqno == seq) {
+ packet = entry;
+ break;
+ }
-EXPORT_SYMBOL_GPL(dccp_rx_hist_purge);
+ if (packet)
+ *ccval = packet->dccphrx_ccval;
+
+ return packet != NULL;
+}
+EXPORT_SYMBOL_GPL(dccp_rx_hist_find_entry);
struct dccp_rx_hist_entry *
dccp_rx_hist_find_data_packet(const struct list_head *list)
{
EXPORT_SYMBOL_GPL(dccp_rx_hist_find_data_packet);
-int dccp_rx_hist_add_packet(struct dccp_rx_hist *hist,
+void dccp_rx_hist_add_packet(struct dccp_rx_hist *hist,
struct list_head *rx_list,
struct list_head *li_list,
- struct dccp_rx_hist_entry *packet)
+ struct dccp_rx_hist_entry *packet,
+ u64 nonloss_seqno)
{
- struct dccp_rx_hist_entry *entry, *next, *iter;
+ struct dccp_rx_hist_entry *entry, *next;
u8 num_later = 0;
- iter = dccp_rx_hist_head(rx_list);
- if (iter == NULL)
- dccp_rx_hist_add_entry(rx_list, packet);
- else {
- const u64 seqno = packet->dccphrx_seqno;
-
- if (after48(seqno, iter->dccphrx_seqno))
- dccp_rx_hist_add_entry(rx_list, packet);
- else {
- if (dccp_rx_hist_entry_data_packet(iter))
- num_later = 1;
-
- list_for_each_entry_continue(iter, rx_list,
- dccphrx_node) {
- if (after48(seqno, iter->dccphrx_seqno)) {
- dccp_rx_hist_add_entry(&iter->dccphrx_node,
- packet);
- goto trim_history;
- }
-
- if (dccp_rx_hist_entry_data_packet(iter))
- num_later++;
+ list_add(&packet->dccphrx_node, rx_list);
- if (num_later == TFRC_RECV_NUM_LATE_LOSS) {
- dccp_rx_hist_entry_delete(hist, packet);
- return 1;
- }
- }
-
- if (num_later < TFRC_RECV_NUM_LATE_LOSS)
- dccp_rx_hist_add_entry(rx_list, packet);
- /*
- * FIXME: else what? should we destroy the packet
- * like above?
- */
- }
- }
-
-trim_history:
- /*
- * Trim history (remove all packets after the NUM_LATE_LOSS + 1
- * data packets)
- */
num_later = TFRC_RECV_NUM_LATE_LOSS + 1;
if (!list_empty(li_list)) {
list_for_each_entry_safe(entry, next, rx_list, dccphrx_node) {
if (num_later == 0) {
- list_del_init(&entry->dccphrx_node);
- dccp_rx_hist_entry_delete(hist, entry);
+ if (after48(nonloss_seqno,
+ entry->dccphrx_seqno)) {
+ list_del_init(&entry->dccphrx_node);
+ dccp_rx_hist_entry_delete(hist, entry);
+ }
} else if (dccp_rx_hist_entry_data_packet(entry))
--num_later;
}
--num_later;
}
}
-
- return 0;
}
EXPORT_SYMBOL_GPL(dccp_rx_hist_add_packet);
-u64 dccp_rx_hist_detect_loss(struct list_head *rx_list,
- struct list_head *li_list, u8 *win_loss)
-{
- struct dccp_rx_hist_entry *entry, *next, *packet;
- struct dccp_rx_hist_entry *a_loss = NULL;
- struct dccp_rx_hist_entry *b_loss = NULL;
- u64 seq_loss = DCCP_MAX_SEQNO + 1;
- u8 num_later = TFRC_RECV_NUM_LATE_LOSS;
-
- list_for_each_entry_safe(entry, next, rx_list, dccphrx_node) {
- if (num_later == 0) {
- b_loss = entry;
- break;
- } else if (dccp_rx_hist_entry_data_packet(entry))
- --num_later;
- }
-
- if (b_loss == NULL)
- goto out;
-
- num_later = 1;
- list_for_each_entry_safe_continue(entry, next, rx_list, dccphrx_node) {
- if (num_later == 0) {
- a_loss = entry;
- break;
- } else if (dccp_rx_hist_entry_data_packet(entry))
- --num_later;
- }
-
- if (a_loss == NULL) {
- if (list_empty(li_list)) {
- /* no loss event have occured yet */
- LIMIT_NETDEBUG("%s: TODO: find a lost data packet by "
- "comparing to initial seqno\n",
- __FUNCTION__);
- goto out;
- } else {
- LIMIT_NETDEBUG("%s: Less than 4 data pkts in history!",
- __FUNCTION__);
- goto out;
- }
- }
-
- /* Locate a lost data packet */
- entry = packet = b_loss;
- list_for_each_entry_safe_continue(entry, next, rx_list, dccphrx_node) {
- u64 delta = dccp_delta_seqno(entry->dccphrx_seqno,
- packet->dccphrx_seqno);
-
- if (delta != 0) {
- if (dccp_rx_hist_entry_data_packet(packet))
- --delta;
- /*
- * FIXME: check this, probably this % usage is because
- * in earlier drafts the ndp count was just 8 bits
- * long, but now it cam be up to 24 bits long.
- */
-#if 0
- if (delta % DCCP_NDP_LIMIT !=
- (packet->dccphrx_ndp -
- entry->dccphrx_ndp) % DCCP_NDP_LIMIT)
-#endif
- if (delta != packet->dccphrx_ndp - entry->dccphrx_ndp) {
- seq_loss = entry->dccphrx_seqno;
- dccp_inc_seqno(&seq_loss);
- }
- }
- packet = entry;
- if (packet == a_loss)
- break;
- }
-out:
- if (seq_loss != DCCP_MAX_SEQNO + 1)
- *win_loss = a_loss->dccphrx_ccval;
- else
- *win_loss = 0; /* Paranoia */
-
- return seq_loss;
-}
-
-EXPORT_SYMBOL_GPL(dccp_rx_hist_detect_loss);
-
-struct dccp_tx_hist *dccp_tx_hist_new(const char *name)
-{
- struct dccp_tx_hist *hist = kmalloc(sizeof(*hist), GFP_ATOMIC);
- static const char dccp_tx_hist_mask[] = "tx_hist_%s";
- char *slab_name;
-
- if (hist == NULL)
- goto out;
-
- slab_name = kmalloc(strlen(name) + sizeof(dccp_tx_hist_mask) - 1,
- GFP_ATOMIC);
- if (slab_name == NULL)
- goto out_free_hist;
-
- sprintf(slab_name, dccp_tx_hist_mask, name);
- hist->dccptxh_slab = kmem_cache_create(slab_name,
- sizeof(struct dccp_tx_hist_entry),
- 0, SLAB_HWCACHE_ALIGN,
- NULL, NULL);
- if (hist->dccptxh_slab == NULL)
- goto out_free_slab_name;
-out:
- return hist;
-out_free_slab_name:
- kfree(slab_name);
-out_free_hist:
- kfree(hist);
- hist = NULL;
- goto out;
-}
-
-EXPORT_SYMBOL_GPL(dccp_tx_hist_new);
-
-void dccp_tx_hist_delete(struct dccp_tx_hist *hist)
-{
- const char* name = kmem_cache_name(hist->dccptxh_slab);
-
- kmem_cache_destroy(hist->dccptxh_slab);
- kfree(name);
- kfree(hist);
-}
-
-EXPORT_SYMBOL_GPL(dccp_tx_hist_delete);
-
-struct dccp_tx_hist_entry *
- dccp_tx_hist_find_entry(const struct list_head *list, const u64 seq)
-{
- struct dccp_tx_hist_entry *packet = NULL, *entry;
-
- list_for_each_entry(entry, list, dccphtx_node)
- if (entry->dccphtx_seqno == seq) {
- packet = entry;
- break;
- }
-
- return packet;
-}
-
-EXPORT_SYMBOL_GPL(dccp_tx_hist_find_entry);
-
-void dccp_tx_hist_purge_older(struct dccp_tx_hist *hist,
- struct list_head *list,
- struct dccp_tx_hist_entry *packet)
+void dccp_rx_hist_purge(struct dccp_rx_hist *hist, struct list_head *list)
{
- struct dccp_tx_hist_entry *next;
+ struct dccp_rx_hist_entry *entry, *next;
- list_for_each_entry_safe_continue(packet, next, list, dccphtx_node) {
- list_del_init(&packet->dccphtx_node);
- dccp_tx_hist_entry_delete(hist, packet);
+ list_for_each_entry_safe(entry, next, list, dccphrx_node) {
+ list_del_init(&entry->dccphrx_node);
+ kmem_cache_free(hist->dccprxh_slab, entry);
}
}
-EXPORT_SYMBOL_GPL(dccp_tx_hist_purge_older);
-
-void dccp_tx_hist_purge(struct dccp_tx_hist *hist, struct list_head *list)
-{
- struct dccp_tx_hist_entry *entry, *next;
-
- list_for_each_entry_safe(entry, next, list, dccphtx_node) {
- list_del_init(&entry->dccphtx_node);
- dccp_tx_hist_entry_delete(hist, entry);
- }
-}
+EXPORT_SYMBOL_GPL(dccp_rx_hist_purge);
-EXPORT_SYMBOL_GPL(dccp_tx_hist_purge);
-MODULE_AUTHOR("Ian McDonald <iam4@cs.waikato.ac.nz>, "
+MODULE_AUTHOR("Ian McDonald <ian.mcdonald@jandi.co.nz>, "
"Arnaldo Carvalho de Melo <acme@ghostprotocols.net>");
MODULE_DESCRIPTION("DCCP TFRC library");
MODULE_LICENSE("GPL");