2 * Copyright 1997 Massachusetts Institute of Technology
4 * Permission to use, copy, modify, and distribute this software and
5 * its documentation for any purpose and without fee is hereby
6 * granted, provided that both the above copyright notice and this
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16 * THIS SOFTWARE IS PROVIDED BY M.I.T. ``AS IS''. M.I.T. DISCLAIMS
17 * ALL EXPRESS OR IMPLIED WARRANTIES WITH REGARD TO THIS SOFTWARE,
18 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
19 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT
20 * SHALL M.I.T. BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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29 * $FreeBSD: src/sys/net/hostcache.c,v 1.6.2.1 2002/04/14 21:41:48 luigi Exp $
30 * $DragonFly: src/sys/net/Attic/hostcache.c,v 1.2 2003/06/17 04:28:47 dillon Exp $
33 #include <sys/param.h>
34 #include <sys/systm.h>
35 #include <sys/kernel.h>
36 #include <sys/malloc.h>
37 #include <sys/socket.h>
39 #include <net/hostcache.h>
40 #include <net/route.h>
42 MALLOC_DEFINE(M_HOSTCACHE, "hostcache", "per-host cache structure");
44 static struct hctable hctable[AF_MAX];
45 static int hc_timeout_interval = 120;
46 static int hc_maxidle = 1800;
48 static int cmpsa(const struct sockaddr *sa1, const struct sockaddr *sa2);
49 static void hc_timeout(void *xhct);
50 static void maybe_bump_hash(struct hctable *hct);
53 hc_init(int af, struct hccallback *hccb, int init_nelem, int primes)
61 if (hct->hct_nentries)
65 heads = phashinit(init_nelem, M_HOSTCACHE, &nelem);
68 MALLOC(heads, struct hchead *, nelem * sizeof *heads,
69 M_HOSTCACHE, M_WAITOK);
70 for (i = 0; i < nelem; i++) {
75 hct->hct_heads = heads;
76 hct->hct_nentries = nelem;
77 hct->hct_primes = primes;
78 timeout(hc_timeout, hct, hc_timeout_interval * hz);
83 hc_get(struct sockaddr *sa)
90 hct = &hctable[sa->sa_family];
91 if (hct->hct_nentries == 0)
93 hash = hct->hct_cb->hccb_hash(sa, hct->hct_nentries);
94 hc = hct->hct_heads[hash].lh_first;
95 for (; hc; hc = hc->hc_link.le_next) {
96 if (cmpsa(hc->hc_host, sa) == 0)
102 if (hc->hc_rt && (hc->hc_rt->rt_flags & RTF_UP) == 0) {
106 if (hc->hc_rt == 0) {
107 hc->hc_rt = rtalloc1(hc->hc_host, 1, 0);
111 /* XXX move to front of list? */
116 hc_ref(struct hcentry *hc)
119 if (hc->hc_refcnt++ == 0) {
120 hc->hc_hct->hct_idle--;
121 hc->hc_hct->hct_active++;
127 hc_rele(struct hcentry *hc)
131 printf("hc_rele: %p: negative refcnt!\n", (void *)hc);
134 if (hc->hc_refcnt == 0) {
135 hc->hc_hct->hct_idle++;
136 hc->hc_hct->hct_active--;
137 hc->hc_idlesince = mono_time; /* XXX right one? */
143 * The user is expected to initialize hc_host with the address and everything
144 * else to the appropriate form of `0'.
147 hc_insert(struct hcentry *hc)
154 hct = &hctable[hc->hc_host->sa_family];
155 hash = hct->hct_cb->hccb_hash(hc->hc_host, hct->hct_nentries);
157 hc2 = hct->hct_heads[hash].lh_first;
158 for (; hc2; hc2 = hc2->hc_link.le_next) {
159 if (cmpsa(hc2->hc_host, hc->hc_host) == 0)
166 LIST_INSERT_HEAD(&hct->hct_heads[hash], hc, hc_link);
169 * If the table is now more than 75% full, consider bumping it.
171 if (100 * (hct->hct_idle + hct->hct_active) > 75 * hct->hct_nentries)
172 maybe_bump_hash(hct);
178 * It's not clear to me how much sense this makes as an external interface,
179 * since it is expected that the deletion will normally be handled by
183 hc_delete(struct hcentry *hc)
188 if (hc->hc_refcnt > 0)
192 error = hct->hct_cb->hccb_delete(hc);
197 LIST_REMOVE(hc, hc_link);
198 hc->hc_hct->hct_idle--;
200 free(hc, M_HOSTCACHE);
205 hc_timeout(void *xhct)
213 start = mono_time.tv_sec; /* for simplicity */
215 if (hct->hct_idle == 0)
217 for (j = 0; j < hct->hct_nentries; j++) {
218 for (hc = hct->hct_heads[j].lh_first; hc;
219 hc = hc->hc_link.le_next) {
220 if (hc->hc_refcnt > 0)
222 if (hc->hc_idlesince.tv_sec + hc_maxidle <= start) {
223 if (hct->hct_cb->hccb_delete(hc))
226 LIST_REMOVE(hc, hc_link);
233 * Fiddle something here based on tot_idle...
235 timeout(hc_timeout, xhct, hc_timeout_interval * hz);
239 cmpsa(const struct sockaddr *sa1, const struct sockaddr *sa2)
241 if (sa1->sa_len != sa2->sa_len)
242 return ((int)sa1->sa_len - sa2->sa_len);
243 return bcmp(sa1, sa2, sa1->sa_len);
247 maybe_bump_hash(struct hctable *hct)
249 ; /* XXX fill me in */