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
7 * permission notice appear in all copies, that both the above
8 * copyright notice and this permission notice appear in all
9 * supporting documentation, and that the name of M.I.T. not be used
10 * in advertising or publicity pertaining to distribution of the
11 * software without specific, written prior permission. M.I.T. makes
12 * no representations about the suitability of this software for any
13 * purpose. It is provided "as is" without express or implied
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,
21 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
22 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
23 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
24 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
25 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
26 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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 1.8 2006/09/05 00:55:46 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>
38 #include <sys/thread2.h>
40 #include <net/hostcache.h>
41 #include <net/route.h>
43 MALLOC_DEFINE(M_HOSTCACHE
, "hostcache", "per-host cache structure");
45 static struct hctable hctable
[AF_MAX
];
46 static int hc_timeout_interval
= 120;
47 static int hc_maxidle
= 1800;
48 static struct callout hc_timeout_h
;
50 static int cmpsa(const struct sockaddr
*sa1
, const struct sockaddr
*sa2
);
51 static void hc_timeout(void *xhct
);
52 static void maybe_bump_hash(struct hctable
*hct
);
55 hc_init(int af
, struct hccallback
*hccb
, int init_nelem
, int primes
)
63 if (hct
->hct_nentries
)
67 heads
= phashinit(init_nelem
, M_HOSTCACHE
, &nelem
);
70 MALLOC(heads
, struct hchead
*, nelem
* sizeof *heads
,
71 M_HOSTCACHE
, M_WAITOK
);
72 for (i
= 0; i
< nelem
; i
++) {
77 hct
->hct_heads
= heads
;
78 hct
->hct_nentries
= nelem
;
79 hct
->hct_primes
= primes
;
80 callout_init(&hc_timeout_h
);
81 callout_reset(&hc_timeout_h
, hc_timeout_interval
* hz
, hc_timeout
, hct
);
86 hc_get(struct sockaddr
*sa
)
92 hct
= &hctable
[sa
->sa_family
];
93 if (hct
->hct_nentries
== 0)
95 hash
= hct
->hct_cb
->hccb_hash(sa
, hct
->hct_nentries
);
96 hc
= hct
->hct_heads
[hash
].lh_first
;
97 for (; hc
; hc
= hc
->hc_link
.le_next
) {
98 if (cmpsa(hc
->hc_host
, sa
) == 0)
104 if (hc
->hc_rt
&& !(hc
->hc_rt
->rt_flags
& RTF_UP
)) {
108 if (hc
->hc_rt
== NULL
) {
109 hc
->hc_rt
= rtlookup(hc
->hc_host
);
113 /* XXX move to front of list? */
118 hc_ref(struct hcentry
*hc
)
121 if (hc
->hc_refcnt
++ == 0) {
122 hc
->hc_hct
->hct_idle
--;
123 hc
->hc_hct
->hct_active
++;
129 hc_rele(struct hcentry
*hc
)
133 printf("hc_rele: %p: negative refcnt!\n", (void *)hc
);
136 if (hc
->hc_refcnt
== 0) {
137 hc
->hc_hct
->hct_idle
++;
138 hc
->hc_hct
->hct_active
--;
139 hc
->hc_idlesince
= mono_time
; /* XXX right one? */
145 * The user is expected to initialize hc_host with the address and everything
146 * else to the appropriate form of `0'.
149 hc_insert(struct hcentry
*hc
)
155 hct
= &hctable
[hc
->hc_host
->sa_family
];
156 hash
= hct
->hct_cb
->hccb_hash(hc
->hc_host
, hct
->hct_nentries
);
158 hc2
= hct
->hct_heads
[hash
].lh_first
;
159 for (; hc2
; hc2
= hc2
->hc_link
.le_next
) {
160 if (cmpsa(hc2
->hc_host
, hc
->hc_host
) == 0)
167 LIST_INSERT_HEAD(&hct
->hct_heads
[hash
], hc
, hc_link
);
170 * If the table is now more than 75% full, consider bumping it.
172 if (100 * (hct
->hct_idle
+ hct
->hct_active
) > 75 * hct
->hct_nentries
)
173 maybe_bump_hash(hct
);
179 * It's not clear to me how much sense this makes as an external interface,
180 * since it is expected that the deletion will normally be handled by
184 hc_delete(struct hcentry
*hc
)
189 if (hc
->hc_refcnt
> 0)
193 error
= hct
->hct_cb
->hccb_delete(hc
);
198 LIST_REMOVE(hc
, hc_link
);
199 hc
->hc_hct
->hct_idle
--;
201 kfree(hc
, M_HOSTCACHE
);
206 hc_timeout(void *xhct
)
214 start
= mono_time
.tv_sec
; /* for simplicity */
216 if (hct
->hct_idle
== 0)
218 for (j
= 0; j
< hct
->hct_nentries
; j
++) {
219 for (hc
= hct
->hct_heads
[j
].lh_first
; hc
;
220 hc
= hc
->hc_link
.le_next
) {
221 if (hc
->hc_refcnt
> 0)
223 if (hc
->hc_idlesince
.tv_sec
+ hc_maxidle
<= start
) {
224 if (hct
->hct_cb
->hccb_delete(hc
))
227 LIST_REMOVE(hc
, hc_link
);
234 * Fiddle something here based on tot_idle...
236 callout_reset(&hc_timeout_h
, hc_timeout_interval
* hz
,
241 cmpsa(const struct sockaddr
*sa1
, const struct sockaddr
*sa2
)
243 if (sa1
->sa_len
!= sa2
->sa_len
)
244 return ((int)sa1
->sa_len
- sa2
->sa_len
);
245 return bcmp(sa1
, sa2
, sa1
->sa_len
);
249 maybe_bump_hash(struct hctable
*hct
)
251 ; /* XXX fill me in */