1 /*- 2 * Copyright (c) 2010-2011 Juniper Networks, Inc. 3 * All rights reserved. 4 * 5 * This software was developed by Robert N. M. Watson under contract 6 * to Juniper Networks, Inc. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 */ 29 30 #include <sys/cdefs.h> 31 32 __FBSDID("$FreeBSD$"); 33 34 #include "opt_inet6.h" 35 #include "opt_pcbgroup.h" 36 37 #ifndef PCBGROUP 38 #error "options RSS depends on options PCBGROUP" 39 #endif 40 41 #include <sys/param.h> 42 #include <sys/mbuf.h> 43 #include <sys/socket.h> 44 #include <sys/priv.h> 45 #include <sys/kernel.h> 46 #include <sys/smp.h> 47 #include <sys/sysctl.h> 48 #include <sys/sbuf.h> 49 50 #include <net/if.h> 51 #include <net/if_var.h> 52 #include <net/netisr.h> 53 #include <net/rss_config.h> 54 55 #include <netinet/in.h> 56 #include <netinet/in_pcb.h> 57 #include <netinet/in_rss.h> 58 #include <netinet/in_var.h> 59 60 /* for software rss hash support */ 61 #include <netinet/ip.h> 62 #include <netinet/tcp.h> 63 #include <netinet/udp.h> 64 65 /* 66 * Hash an IPv4 2-tuple. 67 */ 68 uint32_t 69 rss_hash_ip4_2tuple(struct in_addr src, struct in_addr dst) 70 { 71 uint8_t data[sizeof(src) + sizeof(dst)]; 72 u_int datalen; 73 74 datalen = 0; 75 bcopy(&src, &data[datalen], sizeof(src)); 76 datalen += sizeof(src); 77 bcopy(&dst, &data[datalen], sizeof(dst)); 78 datalen += sizeof(dst); 79 return (rss_hash(datalen, data)); 80 } 81 82 /* 83 * Hash an IPv4 4-tuple. 84 */ 85 uint32_t 86 rss_hash_ip4_4tuple(struct in_addr src, u_short srcport, struct in_addr dst, 87 u_short dstport) 88 { 89 uint8_t data[sizeof(src) + sizeof(dst) + sizeof(srcport) + 90 sizeof(dstport)]; 91 u_int datalen; 92 93 datalen = 0; 94 bcopy(&src, &data[datalen], sizeof(src)); 95 datalen += sizeof(src); 96 bcopy(&dst, &data[datalen], sizeof(dst)); 97 datalen += sizeof(dst); 98 bcopy(&srcport, &data[datalen], sizeof(srcport)); 99 datalen += sizeof(srcport); 100 bcopy(&dstport, &data[datalen], sizeof(dstport)); 101 datalen += sizeof(dstport); 102 return (rss_hash(datalen, data)); 103 } 104 105 /* 106 * Calculate an appropriate ipv4 2-tuple or 4-tuple given the given 107 * IPv4 source/destination address, UDP or TCP source/destination ports 108 * and the protocol type. 109 * 110 * The protocol code may wish to do a software hash of the given 111 * tuple. This depends upon the currently configured RSS hash types. 112 * 113 * This assumes that the packet in question isn't a fragment. 114 * 115 * It also assumes the packet source/destination address 116 * are in "incoming" packet order (ie, source is "far" address.) 117 */ 118 int 119 rss_proto_software_hash_v4(struct in_addr s, struct in_addr d, 120 u_short sp, u_short dp, int proto, 121 uint32_t *hashval, uint32_t *hashtype) 122 { 123 uint32_t hash; 124 125 /* 126 * Next, choose the hash type depending upon the protocol 127 * identifier. 128 */ 129 if ((proto == IPPROTO_TCP) && 130 (rss_gethashconfig() & RSS_HASHTYPE_RSS_TCP_IPV4)) { 131 hash = rss_hash_ip4_4tuple(s, sp, d, dp); 132 *hashval = hash; 133 *hashtype = M_HASHTYPE_RSS_TCP_IPV4; 134 return (0); 135 } else if ((proto == IPPROTO_UDP) && 136 (rss_gethashconfig() & RSS_HASHTYPE_RSS_UDP_IPV4)) { 137 hash = rss_hash_ip4_4tuple(s, sp, d, dp); 138 *hashval = hash; 139 *hashtype = M_HASHTYPE_RSS_UDP_IPV4; 140 return (0); 141 } else if (rss_gethashconfig() & RSS_HASHTYPE_RSS_IPV4) { 142 /* RSS doesn't hash on other protocols like SCTP; so 2-tuple */ 143 hash = rss_hash_ip4_2tuple(s, d); 144 *hashval = hash; 145 *hashtype = M_HASHTYPE_RSS_IPV4; 146 return (0); 147 } 148 149 /* No configured available hashtypes! */ 150 printf("%s: no available hashtypes!\n", __func__); 151 return (-1); 152 } 153 154 /* 155 * Do a software calculation of the RSS for the given mbuf. 156 * 157 * This is typically used by the input path to recalculate the RSS after 158 * some form of packet processing (eg de-capsulation, IP fragment reassembly.) 159 * 160 * dir is the packet direction - RSS_HASH_PKT_INGRESS for incoming and 161 * RSS_HASH_PKT_EGRESS for outgoing. 162 * 163 * Returns 0 if a hash was done, -1 if no hash was done, +1 if 164 * the mbuf already had a valid RSS flowid. 165 * 166 * This function doesn't modify the mbuf. It's up to the caller to 167 * assign flowid/flowtype as appropriate. 168 */ 169 int 170 rss_mbuf_software_hash_v4(const struct mbuf *m, int dir, uint32_t *hashval, 171 uint32_t *hashtype) 172 { 173 const struct ip *ip; 174 const struct tcphdr *th; 175 const struct udphdr *uh; 176 uint32_t flowid; 177 uint32_t flowtype; 178 uint8_t proto; 179 int iphlen; 180 int is_frag = 0; 181 182 /* 183 * XXX For now this only handles hashing on incoming mbufs. 184 */ 185 if (dir != RSS_HASH_PKT_INGRESS) { 186 printf("%s: called on EGRESS packet!\n", __func__); 187 return (-1); 188 } 189 190 /* 191 * First, validate that the mbuf we have is long enough 192 * to have an IPv4 header in it. 193 */ 194 if (m->m_pkthdr.len < (sizeof(struct ip))) { 195 printf("%s: short mbuf pkthdr\n", __func__); 196 return (-1); 197 } 198 if (m->m_len < (sizeof(struct ip))) { 199 printf("%s: short mbuf len\n", __func__); 200 return (-1); 201 } 202 203 /* Ok, let's dereference that */ 204 ip = mtod(m, struct ip *); 205 proto = ip->ip_p; 206 iphlen = ip->ip_hl << 2; 207 208 /* 209 * If this is a fragment then it shouldn't be four-tuple 210 * hashed just yet. Once it's reassembled into a full 211 * frame it should be re-hashed. 212 */ 213 if (ip->ip_off & htons(IP_MF | IP_OFFMASK)) 214 is_frag = 1; 215 216 /* 217 * If the mbuf flowid/flowtype matches the packet type, 218 * and we don't support the 4-tuple version of the given protocol, 219 * then signal to the owner that it can trust the flowid/flowtype 220 * details. 221 * 222 * This is a little picky - eg, if TCPv4 / UDPv4 hashing 223 * is supported but we got a TCP/UDP frame only 2-tuple hashed, 224 * then we shouldn't just "trust" the 2-tuple hash. We need 225 * a 4-tuple hash. 226 */ 227 flowid = m->m_pkthdr.flowid; 228 flowtype = M_HASHTYPE_GET(m); 229 230 if (flowtype != M_HASHTYPE_NONE) { 231 switch (proto) { 232 case IPPROTO_UDP: 233 if ((rss_gethashconfig() & RSS_HASHTYPE_RSS_UDP_IPV4) && 234 (flowtype == M_HASHTYPE_RSS_UDP_IPV4) && 235 (is_frag == 0)) { 236 return (1); 237 } 238 /* 239 * Only allow 2-tuple for UDP frames if we don't also 240 * support 4-tuple for UDP. 241 */ 242 if ((rss_gethashconfig() & RSS_HASHTYPE_RSS_IPV4) && 243 ((rss_gethashconfig() & RSS_HASHTYPE_RSS_UDP_IPV4) == 0) && 244 flowtype == M_HASHTYPE_RSS_IPV4) { 245 return (1); 246 } 247 break; 248 case IPPROTO_TCP: 249 if ((rss_gethashconfig() & RSS_HASHTYPE_RSS_TCP_IPV4) && 250 (flowtype == M_HASHTYPE_RSS_TCP_IPV4) && 251 (is_frag == 0)) { 252 return (1); 253 } 254 /* 255 * Only allow 2-tuple for TCP frames if we don't also 256 * support 2-tuple for TCP. 257 */ 258 if ((rss_gethashconfig() & RSS_HASHTYPE_RSS_IPV4) && 259 ((rss_gethashconfig() & RSS_HASHTYPE_RSS_TCP_IPV4) == 0) && 260 flowtype == M_HASHTYPE_RSS_IPV4) { 261 return (1); 262 } 263 break; 264 default: 265 if ((rss_gethashconfig() & RSS_HASHTYPE_RSS_IPV4) && 266 flowtype == M_HASHTYPE_RSS_IPV4) { 267 return (1); 268 } 269 break; 270 } 271 } 272 273 /* 274 * Decode enough information to make a hash decision. 275 * 276 * XXX TODO: does the hardware hash on 4-tuple if IP 277 * options are present? 278 */ 279 if ((rss_gethashconfig() & RSS_HASHTYPE_RSS_TCP_IPV4) && 280 (proto == IPPROTO_TCP) && 281 (is_frag == 0)) { 282 if (m->m_len < iphlen + sizeof(struct tcphdr)) { 283 printf("%s: short TCP frame?\n", __func__); 284 return (-1); 285 } 286 th = (const struct tcphdr *)((c_caddr_t)ip + iphlen); 287 return rss_proto_software_hash_v4(ip->ip_src, ip->ip_dst, 288 th->th_sport, 289 th->th_dport, 290 proto, 291 hashval, 292 hashtype); 293 } else if ((rss_gethashconfig() & RSS_HASHTYPE_RSS_UDP_IPV4) && 294 (proto == IPPROTO_UDP) && 295 (is_frag == 0)) { 296 uh = (const struct udphdr *)((c_caddr_t)ip + iphlen); 297 if (m->m_len < iphlen + sizeof(struct udphdr)) { 298 printf("%s: short UDP frame?\n", __func__); 299 return (-1); 300 } 301 return rss_proto_software_hash_v4(ip->ip_src, ip->ip_dst, 302 uh->uh_sport, 303 uh->uh_dport, 304 proto, 305 hashval, 306 hashtype); 307 } else if (rss_gethashconfig() & RSS_HASHTYPE_RSS_IPV4) { 308 /* Default to 2-tuple hash */ 309 return rss_proto_software_hash_v4(ip->ip_src, ip->ip_dst, 310 0, /* source port */ 311 0, /* destination port */ 312 0, /* IPPROTO_IP */ 313 hashval, 314 hashtype); 315 } else { 316 printf("%s: no available hashtypes!\n", __func__); 317 return (-1); 318 } 319 } 320 321 /* 322 * Similar to rss_m2cpuid, but designed to be used by the IP NETISR 323 * on incoming frames. 324 * 325 * If an existing RSS hash exists and it matches what the configured 326 * hashing is, then use it. 327 * 328 * If there's an existing RSS hash but the desired hash is different, 329 * or if there's no useful RSS hash, then calculate it via 330 * the software path. 331 * 332 * XXX TODO: definitely want statistics here! 333 */ 334 struct mbuf * 335 rss_soft_m2cpuid(struct mbuf *m, uintptr_t source, u_int *cpuid) 336 { 337 uint32_t hash_val, hash_type; 338 int ret; 339 340 M_ASSERTPKTHDR(m); 341 342 ret = rss_mbuf_software_hash_v4(m, RSS_HASH_PKT_INGRESS, 343 &hash_val, &hash_type); 344 if (ret > 0) { 345 /* mbuf has a valid hash already; don't need to modify it */ 346 *cpuid = rss_hash2cpuid(m->m_pkthdr.flowid, M_HASHTYPE_GET(m)); 347 } else if (ret == 0) { 348 /* hash was done; update */ 349 m->m_pkthdr.flowid = hash_val; 350 M_HASHTYPE_SET(m, hash_type); 351 *cpuid = rss_hash2cpuid(m->m_pkthdr.flowid, M_HASHTYPE_GET(m)); 352 } else { /* ret < 0 */ 353 /* no hash was done */ 354 *cpuid = NETISR_CPUID_NONE; 355 } 356 return (m); 357 } 358