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-rw-r--r--pfinet/linux-src/net/core/dst.c145
1 files changed, 145 insertions, 0 deletions
diff --git a/pfinet/linux-src/net/core/dst.c b/pfinet/linux-src/net/core/dst.c
new file mode 100644
index 00000000..9007dde6
--- /dev/null
+++ b/pfinet/linux-src/net/core/dst.c
@@ -0,0 +1,145 @@
+/*
+ * net/dst.c Protocol independent destination cache.
+ *
+ * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
+ *
+ */
+
+#include <asm/segment.h>
+#include <asm/system.h>
+#include <asm/bitops.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/string.h>
+#include <linux/errno.h>
+#include <linux/netdevice.h>
+#include <linux/skbuff.h>
+
+#include <net/dst.h>
+
+struct dst_entry * dst_garbage_list;
+atomic_t dst_total = ATOMIC_INIT(0);
+
+static unsigned long dst_gc_timer_expires;
+static unsigned long dst_gc_timer_inc = DST_GC_MAX;
+static void dst_run_gc(unsigned long);
+
+static struct timer_list dst_gc_timer =
+ { NULL, NULL, DST_GC_MIN, 0L, dst_run_gc };
+
+#if RT_CACHE_DEBUG >= 2
+atomic_t hh_count;
+#endif
+
+static void dst_run_gc(unsigned long dummy)
+{
+ int delayed = 0;
+ struct dst_entry * dst, **dstp;
+
+ del_timer(&dst_gc_timer);
+ dstp = &dst_garbage_list;
+ while ((dst = *dstp) != NULL) {
+ if (atomic_read(&dst->use)) {
+ dstp = &dst->next;
+ delayed++;
+ continue;
+ }
+ *dstp = dst->next;
+ dst_destroy(dst);
+ }
+ if (!dst_garbage_list) {
+ dst_gc_timer_inc = DST_GC_MAX;
+ return;
+ }
+ if ((dst_gc_timer_expires += dst_gc_timer_inc) > DST_GC_MAX)
+ dst_gc_timer_expires = DST_GC_MAX;
+ dst_gc_timer_inc += DST_GC_INC;
+ dst_gc_timer.expires = jiffies + dst_gc_timer_expires;
+#if RT_CACHE_DEBUG >= 2
+ printk("dst_total: %d/%d %ld\n",
+ atomic_read(&dst_total), delayed, dst_gc_timer_expires);
+#endif
+ add_timer(&dst_gc_timer);
+}
+
+static int dst_discard(struct sk_buff *skb)
+{
+ kfree_skb(skb);
+ return 0;
+}
+
+static int dst_blackhole(struct sk_buff *skb)
+{
+ kfree_skb(skb);
+ return 0;
+}
+
+void * dst_alloc(int size, struct dst_ops * ops)
+{
+ struct dst_entry * dst;
+
+ if (ops->gc && atomic_read(&ops->entries) > ops->gc_thresh) {
+ if (ops->gc())
+ return NULL;
+ }
+ dst = kmalloc(size, GFP_ATOMIC);
+ if (!dst)
+ return NULL;
+ memset(dst, 0, size);
+ dst->ops = ops;
+ atomic_set(&dst->refcnt, 0);
+ dst->lastuse = jiffies;
+ dst->input = dst_discard;
+ dst->output = dst_blackhole;
+ atomic_inc(&dst_total);
+ atomic_inc(&ops->entries);
+ return dst;
+}
+
+void __dst_free(struct dst_entry * dst)
+{
+ start_bh_atomic();
+ /* The first case (dev==NULL) is required, when
+ protocol module is unloaded.
+ */
+ if (dst->dev == NULL || !(dst->dev->flags&IFF_UP)) {
+ dst->input = dst_discard;
+ dst->output = dst_blackhole;
+ dst->dev = &loopback_dev;
+ }
+ dst->obsolete = 2;
+ dst->next = dst_garbage_list;
+ dst_garbage_list = dst;
+ if (dst_gc_timer_inc > DST_GC_INC) {
+ del_timer(&dst_gc_timer);
+ dst_gc_timer_inc = DST_GC_INC;
+ dst_gc_timer_expires = DST_GC_MIN;
+ dst_gc_timer.expires = jiffies + dst_gc_timer_expires;
+ add_timer(&dst_gc_timer);
+ }
+ end_bh_atomic();
+}
+
+void dst_destroy(struct dst_entry * dst)
+{
+ struct neighbour *neigh = dst->neighbour;
+ struct hh_cache *hh = dst->hh;
+
+ dst->hh = NULL;
+ if (hh && atomic_dec_and_test(&hh->hh_refcnt))
+ kfree(hh);
+
+ if (neigh) {
+ dst->neighbour = NULL;
+ neigh_release(neigh);
+ }
+
+ atomic_dec(&dst->ops->entries);
+
+ if (dst->ops->destroy)
+ dst->ops->destroy(dst);
+ atomic_dec(&dst_total);
+ kfree(dst);
+}