1 /*- 2 * Copyright (c) 2008 Isilon Inc http://www.isilon.com/ 3 * Authors: Doug Rabson <dfr@rabson.org> 4 * Developed with Red Inc: Alfred Perlstein <alfred@freebsd.org> 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 */ 27 28 #include <sys/cdefs.h> 29 __FBSDID("$FreeBSD$"); 30 31 #include <sys/param.h> 32 #include <sys/hash.h> 33 #include <sys/kernel.h> 34 #include <sys/lock.h> 35 #include <sys/mbuf.h> 36 #include <sys/mutex.h> 37 #include <sys/queue.h> 38 39 #include <rpc/rpc.h> 40 #include <rpc/replay.h> 41 42 struct replay_cache_entry { 43 int rce_hash; 44 struct rpc_msg rce_msg; 45 struct sockaddr_storage rce_addr; 46 struct rpc_msg rce_repmsg; 47 struct mbuf *rce_repbody; 48 49 TAILQ_ENTRY(replay_cache_entry) rce_link; 50 TAILQ_ENTRY(replay_cache_entry) rce_alllink; 51 }; 52 TAILQ_HEAD(replay_cache_list, replay_cache_entry); 53 54 static struct replay_cache_entry * 55 replay_alloc(struct replay_cache *rc, struct rpc_msg *msg, 56 struct sockaddr *addr, int h); 57 static void replay_free(struct replay_cache *rc, 58 struct replay_cache_entry *rce); 59 static void replay_prune(struct replay_cache *rc); 60 61 #define REPLAY_HASH_SIZE 256 62 #define REPLAY_MAX 1024 63 64 struct replay_cache { 65 struct replay_cache_list rc_cache[REPLAY_HASH_SIZE]; 66 struct replay_cache_list rc_all; 67 struct mtx rc_lock; 68 int rc_count; 69 size_t rc_size; 70 size_t rc_maxsize; 71 }; 72 73 struct replay_cache * 74 replay_newcache(size_t maxsize) 75 { 76 struct replay_cache *rc; 77 int i; 78 79 rc = malloc(sizeof(*rc), M_RPC, M_WAITOK|M_ZERO); 80 for (i = 0; i < REPLAY_HASH_SIZE; i++) 81 TAILQ_INIT(&rc->rc_cache[i]); 82 TAILQ_INIT(&rc->rc_all); 83 mtx_init(&rc->rc_lock, "rc_lock", NULL, MTX_DEF); 84 rc->rc_maxsize = maxsize; 85 86 return (rc); 87 } 88 89 void 90 replay_setsize(struct replay_cache *rc, size_t newmaxsize) 91 { 92 93 rc->rc_maxsize = newmaxsize; 94 replay_prune(rc); 95 } 96 97 void 98 replay_freecache(struct replay_cache *rc) 99 { 100 101 mtx_lock(&rc->rc_lock); 102 while (TAILQ_FIRST(&rc->rc_all)) 103 replay_free(rc, TAILQ_FIRST(&rc->rc_all)); 104 mtx_destroy(&rc->rc_lock); 105 free(rc, M_RPC); 106 } 107 108 static struct replay_cache_entry * 109 replay_alloc(struct replay_cache *rc, 110 struct rpc_msg *msg, struct sockaddr *addr, int h) 111 { 112 struct replay_cache_entry *rce; 113 114 rc->rc_count++; 115 rce = malloc(sizeof(*rce), M_RPC, M_NOWAIT|M_ZERO); 116 rce->rce_hash = h; 117 rce->rce_msg = *msg; 118 bcopy(addr, &rce->rce_addr, addr->sa_len); 119 120 TAILQ_INSERT_HEAD(&rc->rc_cache[h], rce, rce_link); 121 TAILQ_INSERT_HEAD(&rc->rc_all, rce, rce_alllink); 122 123 return (rce); 124 } 125 126 static void 127 replay_free(struct replay_cache *rc, struct replay_cache_entry *rce) 128 { 129 130 rc->rc_count--; 131 TAILQ_REMOVE(&rc->rc_cache[rce->rce_hash], rce, rce_link); 132 TAILQ_REMOVE(&rc->rc_all, rce, rce_alllink); 133 if (rce->rce_repbody) { 134 rc->rc_size -= m_length(rce->rce_repbody, NULL); 135 m_freem(rce->rce_repbody); 136 } 137 free(rce, M_RPC); 138 } 139 140 static void 141 replay_prune(struct replay_cache *rc) 142 { 143 struct replay_cache_entry *rce; 144 bool_t freed_one; 145 146 if (rc->rc_count >= REPLAY_MAX || rc->rc_size > rc->rc_maxsize) { 147 freed_one = FALSE; 148 do { 149 /* 150 * Try to free an entry. Don't free in-progress entries 151 */ 152 TAILQ_FOREACH_REVERSE(rce, &rc->rc_all, 153 replay_cache_list, rce_alllink) { 154 if (rce->rce_repmsg.rm_xid) { 155 replay_free(rc, rce); 156 freed_one = TRUE; 157 break; 158 } 159 } 160 } while (freed_one 161 && (rc->rc_count >= REPLAY_MAX 162 || rc->rc_size > rc->rc_maxsize)); 163 } 164 } 165 166 enum replay_state 167 replay_find(struct replay_cache *rc, struct rpc_msg *msg, 168 struct sockaddr *addr, struct rpc_msg *repmsg, struct mbuf **mp) 169 { 170 int h = HASHSTEP(HASHINIT, msg->rm_xid) % REPLAY_HASH_SIZE; 171 struct replay_cache_entry *rce; 172 173 mtx_lock(&rc->rc_lock); 174 TAILQ_FOREACH(rce, &rc->rc_cache[h], rce_link) { 175 if (rce->rce_msg.rm_xid == msg->rm_xid 176 && rce->rce_msg.rm_call.cb_prog == msg->rm_call.cb_prog 177 && rce->rce_msg.rm_call.cb_vers == msg->rm_call.cb_vers 178 && rce->rce_msg.rm_call.cb_proc == msg->rm_call.cb_proc 179 && rce->rce_addr.ss_len == addr->sa_len 180 && bcmp(&rce->rce_addr, addr, addr->sa_len) == 0) { 181 if (rce->rce_repmsg.rm_xid) { 182 /* 183 * We have a reply for this 184 * message. Copy it and return. Keep 185 * replay_all LRU sorted 186 */ 187 TAILQ_REMOVE(&rc->rc_all, rce, rce_alllink); 188 TAILQ_INSERT_HEAD(&rc->rc_all, rce, 189 rce_alllink); 190 *repmsg = rce->rce_repmsg; 191 if (rce->rce_repbody) { 192 *mp = m_copym(rce->rce_repbody, 193 0, M_COPYALL, M_NOWAIT); 194 mtx_unlock(&rc->rc_lock); 195 if (!*mp) 196 return (RS_ERROR); 197 } else { 198 mtx_unlock(&rc->rc_lock); 199 } 200 return (RS_DONE); 201 } else { 202 mtx_unlock(&rc->rc_lock); 203 return (RS_INPROGRESS); 204 } 205 } 206 } 207 208 replay_prune(rc); 209 210 rce = replay_alloc(rc, msg, addr, h); 211 212 mtx_unlock(&rc->rc_lock); 213 214 if (!rce) 215 return (RS_ERROR); 216 else 217 return (RS_NEW); 218 } 219 220 void 221 replay_setreply(struct replay_cache *rc, 222 struct rpc_msg *repmsg, struct sockaddr *addr, struct mbuf *m) 223 { 224 int h = HASHSTEP(HASHINIT, repmsg->rm_xid) % REPLAY_HASH_SIZE; 225 struct replay_cache_entry *rce; 226 227 /* 228 * Copy the reply before the lock so we can sleep. 229 */ 230 if (m) 231 m = m_copym(m, 0, M_COPYALL, M_WAITOK); 232 233 mtx_lock(&rc->rc_lock); 234 TAILQ_FOREACH(rce, &rc->rc_cache[h], rce_link) { 235 if (rce->rce_msg.rm_xid == repmsg->rm_xid 236 && rce->rce_addr.ss_len == addr->sa_len 237 && bcmp(&rce->rce_addr, addr, addr->sa_len) == 0) { 238 break; 239 } 240 } 241 if (rce) { 242 rce->rce_repmsg = *repmsg; 243 rce->rce_repbody = m; 244 if (m) 245 rc->rc_size += m_length(m, NULL); 246 } 247 mtx_unlock(&rc->rc_lock); 248 } 249