/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2008 Isilon Inc http://www.isilon.com/
* Authors: Doug Rabson <dfr@rabson.org>
* Developed with Red Inc: Alfred Perlstein <alfred@freebsd.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/hash.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/mutex.h>
#include <sys/queue.h>
#include <rpc/rpc.h>
#include <rpc/replay.h>
struct replay_cache_entry {
int rce_hash;
struct rpc_msg rce_msg;
struct sockaddr_storage rce_addr;
struct rpc_msg rce_repmsg;
struct mbuf *rce_repbody;
TAILQ_ENTRY(replay_cache_entry) rce_link;
TAILQ_ENTRY(replay_cache_entry) rce_alllink;
};
TAILQ_HEAD(replay_cache_list, replay_cache_entry);
static struct replay_cache_entry *
replay_alloc(struct replay_cache *rc, struct rpc_msg *msg,
struct sockaddr *addr, int h);
static void replay_free(struct replay_cache *rc,
struct replay_cache_entry *rce);
static void replay_prune(struct replay_cache *rc);
#define REPLAY_HASH_SIZE 256
#define REPLAY_MAX 1024
struct replay_cache {
struct replay_cache_list rc_cache[REPLAY_HASH_SIZE];
struct replay_cache_list rc_all;
struct mtx rc_lock;
int rc_count;
size_t rc_size;
size_t rc_maxsize;
};
struct replay_cache *
replay_newcache(size_t maxsize)
{
struct replay_cache *rc;
int i;
rc = malloc(sizeof(*rc), M_RPC, M_WAITOK|M_ZERO);
for (i = 0; i < REPLAY_HASH_SIZE; i++)
TAILQ_INIT(&rc->rc_cache[i]);
TAILQ_INIT(&rc->rc_all);
mtx_init(&rc->rc_lock, "rc_lock", NULL, MTX_DEF);
rc->rc_maxsize = maxsize;
return (rc);
}
void
replay_setsize(struct replay_cache *rc, size_t newmaxsize)
{
mtx_lock(&rc->rc_lock);
rc->rc_maxsize = newmaxsize;
replay_prune(rc);
mtx_unlock(&rc->rc_lock);
}
void
replay_freecache(struct replay_cache *rc)
{
mtx_lock(&rc->rc_lock);
while (TAILQ_FIRST(&rc->rc_all))
replay_free(rc, TAILQ_FIRST(&rc->rc_all));
mtx_destroy(&rc->rc_lock);
free(rc, M_RPC);
}
static struct replay_cache_entry *
replay_alloc(struct replay_cache *rc,
struct rpc_msg *msg, struct sockaddr *addr, int h)
{
struct replay_cache_entry *rce;
mtx_assert(&rc->rc_lock, MA_OWNED);
rc->rc_count++;
rce = malloc(sizeof(*rce), M_RPC, M_NOWAIT|M_ZERO);
if (!rce)
return (NULL);
rce->rce_hash = h;
rce->rce_msg = *msg;
bcopy(addr, &rce->rce_addr, addr->sa_len);
TAILQ_INSERT_HEAD(&rc->rc_cache[h], rce, rce_link);
TAILQ_INSERT_HEAD(&rc->rc_all, rce, rce_alllink);
return (rce);
}
static void
replay_free(struct replay_cache *rc, struct replay_cache_entry *rce)
{
mtx_assert(&rc->rc_lock, MA_OWNED);
rc->rc_count--;
TAILQ_REMOVE(&rc->rc_cache[rce->rce_hash], rce, rce_link);
TAILQ_REMOVE(&rc->rc_all, rce, rce_alllink);
if (rce->rce_repbody) {
rc->rc_size -= m_length(rce->rce_repbody, NULL);
m_freem(rce->rce_repbody);
}
free(rce, M_RPC);
}
static void
replay_prune(struct replay_cache *rc)
{
struct replay_cache_entry *rce;
mtx_assert(&rc->rc_lock, MA_OWNED);
if (rc->rc_count < REPLAY_MAX && rc->rc_size <= rc->rc_maxsize)
return;
do {
/*
* Try to free an entry. Don't free in-progress entries.
*/
TAILQ_FOREACH_REVERSE(rce, &rc->rc_all, replay_cache_list,
rce_alllink) {
if (rce->rce_repmsg.rm_xid)
break;
}
if (rce)
replay_free(rc, rce);
} while (rce && (rc->rc_count >= REPLAY_MAX
|| rc->rc_size > rc->rc_maxsize));
}
enum replay_state
replay_find(struct replay_cache *rc, struct rpc_msg *msg,
struct sockaddr *addr, struct rpc_msg *repmsg, struct mbuf **mp)
{
int h = HASHSTEP(HASHINIT, msg->rm_xid) % REPLAY_HASH_SIZE;
struct replay_cache_entry *rce;
mtx_lock(&rc->rc_lock);
TAILQ_FOREACH(rce, &rc->rc_cache[h], rce_link) {
if (rce->rce_msg.rm_xid == msg->rm_xid
&& rce->rce_msg.rm_call.cb_prog == msg->rm_call.cb_prog
&& rce->rce_msg.rm_call.cb_vers == msg->rm_call.cb_vers
&& rce->rce_msg.rm_call.cb_proc == msg->rm_call.cb_proc
&& rce->rce_addr.ss_len == addr->sa_len
&& bcmp(&rce->rce_addr, addr, addr->sa_len) == 0) {
if (rce->rce_repmsg.rm_xid) {
/*
* We have a reply for this
* message. Copy it and return. Keep
* replay_all LRU sorted
*/
TAILQ_REMOVE(&rc->rc_all, rce, rce_alllink);
TAILQ_INSERT_HEAD(&rc->rc_all, rce,
rce_alllink);
*repmsg = rce->rce_repmsg;
if (rce->rce_repbody) {
*mp = m_copym(rce->rce_repbody,
0, M_COPYALL, M_NOWAIT);
mtx_unlock(&rc->rc_lock);
if (!*mp)
return (RS_ERROR);
} else {
mtx_unlock(&rc->rc_lock);
}
return (RS_DONE);
} else {
mtx_unlock(&rc->rc_lock);
return (RS_INPROGRESS);
}
}
}
replay_prune(rc);
rce = replay_alloc(rc, msg, addr, h);
mtx_unlock(&rc->rc_lock);
if (!rce)
return (RS_ERROR);
else
return (RS_NEW);
}
void
replay_setreply(struct replay_cache *rc,
struct rpc_msg *repmsg, struct sockaddr *addr, struct mbuf *m)
{
int h = HASHSTEP(HASHINIT, repmsg->rm_xid) % REPLAY_HASH_SIZE;
struct replay_cache_entry *rce;
/*
* Copy the reply before the lock so we can sleep.
*/
if (m)
m = m_copym(m, 0, M_COPYALL, M_WAITOK);
mtx_lock(&rc->rc_lock);
TAILQ_FOREACH(rce, &rc->rc_cache[h], rce_link) {
if (rce->rce_msg.rm_xid == repmsg->rm_xid
&& rce->rce_addr.ss_len == addr->sa_len
&& bcmp(&rce->rce_addr, addr, addr->sa_len) == 0) {
break;
}
}
if (rce) {
rce->rce_repmsg = *repmsg;
rce->rce_repbody = m;
if (m)
rc->rc_size += m_length(m, NULL);
}
mtx_unlock(&rc->rc_lock);
}
