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 mtx_lock(&rc->rc_lock); 94 rc->rc_maxsize = newmaxsize; 95 replay_prune(rc); 96 mtx_unlock(&rc->rc_lock); 97 } 98 99 void 100 replay_freecache(struct replay_cache *rc) 101 { 102 103 mtx_lock(&rc->rc_lock); 104 while (TAILQ_FIRST(&rc->rc_all)) 105 replay_free(rc, TAILQ_FIRST(&rc->rc_all)); 106 mtx_destroy(&rc->rc_lock); 107 free(rc, M_RPC); 108 } 109 110 static struct replay_cache_entry * 111 replay_alloc(struct replay_cache *rc, 112 struct rpc_msg *msg, struct sockaddr *addr, int h) 113 { 114 struct replay_cache_entry *rce; 115 116 mtx_assert(&rc->rc_lock, MA_OWNED); 117 118 rc->rc_count++; 119 rce = malloc(sizeof(*rce), M_RPC, M_NOWAIT|M_ZERO); 120 if (!rce) 121 return (NULL); 122 rce->rce_hash = h; 123 rce->rce_msg = *msg; 124 bcopy(addr, &rce->rce_addr, addr->sa_len); 125 126 TAILQ_INSERT_HEAD(&rc->rc_cache[h], rce, rce_link); 127 TAILQ_INSERT_HEAD(&rc->rc_all, rce, rce_alllink); 128 129 return (rce); 130 } 131 132 static void 133 replay_free(struct replay_cache *rc, struct replay_cache_entry *rce) 134 { 135 136 mtx_assert(&rc->rc_lock, MA_OWNED); 137 138 rc->rc_count--; 139 TAILQ_REMOVE(&rc->rc_cache[rce->rce_hash], rce, rce_link); 140 TAILQ_REMOVE(&rc->rc_all, rce, rce_alllink); 141 if (rce->rce_repbody) { 142 rc->rc_size -= m_length(rce->rce_repbody, NULL); 143 m_freem(rce->rce_repbody); 144 } 145 free(rce, M_RPC); 146 } 147 148 static void 149 replay_prune(struct replay_cache *rc) 150 { 151 struct replay_cache_entry *rce; 152 153 mtx_assert(&rc->rc_lock, MA_OWNED); 154 155 if (rc->rc_count < REPLAY_MAX && rc->rc_size <= rc->rc_maxsize) 156 return; 157 158 do { 159 /* 160 * Try to free an entry. Don't free in-progress entries. 161 */ 162 TAILQ_FOREACH_REVERSE(rce, &rc->rc_all, replay_cache_list, 163 rce_alllink) { 164 if (rce->rce_repmsg.rm_xid) 165 break; 166 } 167 if (rce) 168 replay_free(rc, rce); 169 } while (rce && (rc->rc_count >= REPLAY_MAX 170 || rc->rc_size > rc->rc_maxsize)); 171 } 172 173 enum replay_state 174 replay_find(struct replay_cache *rc, struct rpc_msg *msg, 175 struct sockaddr *addr, struct rpc_msg *repmsg, struct mbuf **mp) 176 { 177 int h = HASHSTEP(HASHINIT, msg->rm_xid) % REPLAY_HASH_SIZE; 178 struct replay_cache_entry *rce; 179 180 mtx_lock(&rc->rc_lock); 181 TAILQ_FOREACH(rce, &rc->rc_cache[h], rce_link) { 182 if (rce->rce_msg.rm_xid == msg->rm_xid 183 && rce->rce_msg.rm_call.cb_prog == msg->rm_call.cb_prog 184 && rce->rce_msg.rm_call.cb_vers == msg->rm_call.cb_vers 185 && rce->rce_msg.rm_call.cb_proc == msg->rm_call.cb_proc 186 && rce->rce_addr.ss_len == addr->sa_len 187 && bcmp(&rce->rce_addr, addr, addr->sa_len) == 0) { 188 if (rce->rce_repmsg.rm_xid) { 189 /* 190 * We have a reply for this 191 * message. Copy it and return. Keep 192 * replay_all LRU sorted 193 */ 194 TAILQ_REMOVE(&rc->rc_all, rce, rce_alllink); 195 TAILQ_INSERT_HEAD(&rc->rc_all, rce, 196 rce_alllink); 197 *repmsg = rce->rce_repmsg; 198 if (rce->rce_repbody) { 199 *mp = m_copym(rce->rce_repbody, 200 0, M_COPYALL, M_NOWAIT); 201 mtx_unlock(&rc->rc_lock); 202 if (!*mp) 203 return (RS_ERROR); 204 } else { 205 mtx_unlock(&rc->rc_lock); 206 } 207 return (RS_DONE); 208 } else { 209 mtx_unlock(&rc->rc_lock); 210 return (RS_INPROGRESS); 211 } 212 } 213 } 214 215 replay_prune(rc); 216 217 rce = replay_alloc(rc, msg, addr, h); 218 219 mtx_unlock(&rc->rc_lock); 220 221 if (!rce) 222 return (RS_ERROR); 223 else 224 return (RS_NEW); 225 } 226 227 void 228 replay_setreply(struct replay_cache *rc, 229 struct rpc_msg *repmsg, struct sockaddr *addr, struct mbuf *m) 230 { 231 int h = HASHSTEP(HASHINIT, repmsg->rm_xid) % REPLAY_HASH_SIZE; 232 struct replay_cache_entry *rce; 233 234 /* 235 * Copy the reply before the lock so we can sleep. 236 */ 237 if (m) 238 m = m_copym(m, 0, M_COPYALL, M_WAITOK); 239 240 mtx_lock(&rc->rc_lock); 241 TAILQ_FOREACH(rce, &rc->rc_cache[h], rce_link) { 242 if (rce->rce_msg.rm_xid == repmsg->rm_xid 243 && rce->rce_addr.ss_len == addr->sa_len 244 && bcmp(&rce->rce_addr, addr, addr->sa_len) == 0) { 245 break; 246 } 247 } 248 if (rce) { 249 rce->rce_repmsg = *repmsg; 250 rce->rce_repbody = m; 251 if (m) 252 rc->rc_size += m_length(m, NULL); 253 } 254 mtx_unlock(&rc->rc_lock); 255 } 256