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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18 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
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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 1.3 2004/09/15 20:38:36 joerg 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;
47 static struct callout hc_timeout_h;
49 static int cmpsa(const struct sockaddr *sa1, const struct sockaddr *sa2);
50 static void hc_timeout(void *xhct);
51 static void maybe_bump_hash(struct hctable *hct);
54 hc_init(int af, struct hccallback *hccb, int init_nelem, int primes)
62 if (hct->hct_nentries)
66 heads = phashinit(init_nelem, M_HOSTCACHE, &nelem);
69 MALLOC(heads, struct hchead *, nelem * sizeof *heads,
70 M_HOSTCACHE, M_WAITOK);
71 for (i = 0; i < nelem; i++) {
76 hct->hct_heads = heads;
77 hct->hct_nentries = nelem;
78 hct->hct_primes = primes;
79 callout_init(&hc_timeout_h);
80 callout_reset(&hc_timeout_h, hc_timeout_interval * hz,
86 hc_get(struct sockaddr *sa)
93 hct = &hctable[sa->sa_family];
94 if (hct->hct_nentries == 0)
96 hash = hct->hct_cb->hccb_hash(sa, hct->hct_nentries);
97 hc = hct->hct_heads[hash].lh_first;
98 for (; hc; hc = hc->hc_link.le_next) {
99 if (cmpsa(hc->hc_host, sa) == 0)
105 if (hc->hc_rt && (hc->hc_rt->rt_flags & RTF_UP) == 0) {
109 if (hc->hc_rt == 0) {
110 hc->hc_rt = rtalloc1(hc->hc_host, 1, 0);
114 /* XXX move to front of list? */
119 hc_ref(struct hcentry *hc)
122 if (hc->hc_refcnt++ == 0) {
123 hc->hc_hct->hct_idle--;
124 hc->hc_hct->hct_active++;
130 hc_rele(struct hcentry *hc)
134 printf("hc_rele: %p: negative refcnt!\n", (void *)hc);
137 if (hc->hc_refcnt == 0) {
138 hc->hc_hct->hct_idle++;
139 hc->hc_hct->hct_active--;
140 hc->hc_idlesince = mono_time; /* XXX right one? */
146 * The user is expected to initialize hc_host with the address and everything
147 * else to the appropriate form of `0'.
150 hc_insert(struct hcentry *hc)
157 hct = &hctable[hc->hc_host->sa_family];
158 hash = hct->hct_cb->hccb_hash(hc->hc_host, hct->hct_nentries);
160 hc2 = hct->hct_heads[hash].lh_first;
161 for (; hc2; hc2 = hc2->hc_link.le_next) {
162 if (cmpsa(hc2->hc_host, hc->hc_host) == 0)
169 LIST_INSERT_HEAD(&hct->hct_heads[hash], hc, hc_link);
172 * If the table is now more than 75% full, consider bumping it.
174 if (100 * (hct->hct_idle + hct->hct_active) > 75 * hct->hct_nentries)
175 maybe_bump_hash(hct);
181 * It's not clear to me how much sense this makes as an external interface,
182 * since it is expected that the deletion will normally be handled by
186 hc_delete(struct hcentry *hc)
191 if (hc->hc_refcnt > 0)
195 error = hct->hct_cb->hccb_delete(hc);
200 LIST_REMOVE(hc, hc_link);
201 hc->hc_hct->hct_idle--;
203 free(hc, M_HOSTCACHE);
208 hc_timeout(void *xhct)
216 start = mono_time.tv_sec; /* for simplicity */
218 if (hct->hct_idle == 0)
220 for (j = 0; j < hct->hct_nentries; j++) {
221 for (hc = hct->hct_heads[j].lh_first; hc;
222 hc = hc->hc_link.le_next) {
223 if (hc->hc_refcnt > 0)
225 if (hc->hc_idlesince.tv_sec + hc_maxidle <= start) {
226 if (hct->hct_cb->hccb_delete(hc))
229 LIST_REMOVE(hc, hc_link);
236 * Fiddle something here based on tot_idle...
238 callout_reset(&hc_timeout_h, hc_timeout_interval * hz,
243 cmpsa(const struct sockaddr *sa1, const struct sockaddr *sa2)
245 if (sa1->sa_len != sa2->sa_len)
246 return ((int)sa1->sa_len - sa2->sa_len);
247 return bcmp(sa1, sa2, sa1->sa_len);
251 maybe_bump_hash(struct hctable *hct)
253 ; /* XXX fill me in */