1 /*- 2 * Copyright (c) 2004 3 * Bosko Milekic <bmilekic@FreeBSD.org>. 4 * All rights reserved. 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 unmodified, this list of conditions and the following 11 * disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the author nor the names of contributors may be 16 * used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 #include <sys/cdefs.h> 33 __FBSDID("$FreeBSD$"); 34 35 #include "opt_mac.h" 36 #include "opt_param.h" 37 38 #include <sys/param.h> 39 #include <sys/mac.h> 40 #include <sys/malloc.h> 41 #include <sys/systm.h> 42 #include <sys/mbuf.h> 43 #include <sys/domain.h> 44 #include <sys/eventhandler.h> 45 #include <sys/kernel.h> 46 #include <sys/protosw.h> 47 #include <sys/smp.h> 48 #include <sys/sysctl.h> 49 50 #include <vm/vm.h> 51 #include <vm/vm_page.h> 52 #include <vm/uma.h> 53 54 /* 55 * In FreeBSD, Mbufs and Mbuf Clusters are allocated from UMA 56 * Zones. 57 * 58 * Mbuf Clusters (2K, contiguous) are allocated from the Cluster 59 * Zone. The Zone can be capped at kern.ipc.nmbclusters, if the 60 * administrator so desires. 61 * 62 * Mbufs are allocated from a UMA Master Zone called the Mbuf 63 * Zone. 64 * 65 * Additionally, FreeBSD provides a Packet Zone, which it 66 * configures as a Secondary Zone to the Mbuf Master Zone, 67 * thus sharing backend Slab kegs with the Mbuf Master Zone. 68 * 69 * Thus common-case allocations and locking are simplified: 70 * 71 * m_clget() m_getcl() 72 * | | 73 * | .------------>[(Packet Cache)] m_get(), m_gethdr() 74 * | | [ Packet ] | 75 * [(Cluster Cache)] [ Secondary ] [ (Mbuf Cache) ] 76 * [ Cluster Zone ] [ Zone ] [ Mbuf Master Zone ] 77 * | \________ | 78 * [ Cluster Keg ] \ / 79 * | [ Mbuf Keg ] 80 * [ Cluster Slabs ] | 81 * | [ Mbuf Slabs ] 82 * \____________(VM)_________________/ 83 */ 84 85 int nmbclusters; 86 struct mbstat mbstat; 87 88 static void 89 tunable_mbinit(void *dummy) 90 { 91 92 /* This has to be done before VM init. */ 93 nmbclusters = 1024 + maxusers * 64; 94 TUNABLE_INT_FETCH("kern.ipc.nmbclusters", &nmbclusters); 95 } 96 SYSINIT(tunable_mbinit, SI_SUB_TUNABLES, SI_ORDER_ANY, tunable_mbinit, NULL); 97 98 SYSCTL_DECL(_kern_ipc); 99 SYSCTL_INT(_kern_ipc, OID_AUTO, nmbclusters, CTLFLAG_RW, &nmbclusters, 0, 100 "Maximum number of mbuf clusters allowed"); 101 SYSCTL_STRUCT(_kern_ipc, OID_AUTO, mbstat, CTLFLAG_RD, &mbstat, mbstat, 102 "Mbuf general information and statistics"); 103 104 /* 105 * Zones from which we allocate. 106 */ 107 uma_zone_t zone_mbuf; 108 uma_zone_t zone_clust; 109 uma_zone_t zone_pack; 110 111 /* 112 * Local prototypes. 113 */ 114 static int mb_ctor_mbuf(void *, int, void *, int); 115 static int mb_ctor_clust(void *, int, void *, int); 116 static int mb_ctor_pack(void *, int, void *, int); 117 static void mb_dtor_mbuf(void *, int, void *); 118 static void mb_dtor_clust(void *, int, void *); /* XXX */ 119 static void mb_dtor_pack(void *, int, void *); /* XXX */ 120 static int mb_init_pack(void *, int, int); 121 static void mb_fini_pack(void *, int); 122 123 static void mb_reclaim(void *); 124 static void mbuf_init(void *); 125 126 /* 127 * Initialize FreeBSD Network buffer allocation. 128 */ 129 SYSINIT(mbuf, SI_SUB_MBUF, SI_ORDER_FIRST, mbuf_init, NULL) 130 static void 131 mbuf_init(void *dummy) 132 { 133 134 /* 135 * Configure UMA zones for Mbufs, Clusters, and Packets. 136 */ 137 zone_mbuf = uma_zcreate("Mbuf", MSIZE, mb_ctor_mbuf, mb_dtor_mbuf, 138 NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_MAXBUCKET); 139 zone_clust = uma_zcreate("MbufClust", MCLBYTES, mb_ctor_clust, 140 mb_dtor_clust, NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_REFCNT); 141 if (nmbclusters > 0) 142 uma_zone_set_max(zone_clust, nmbclusters); 143 zone_pack = uma_zsecond_create("Packet", mb_ctor_pack, mb_dtor_pack, 144 mb_init_pack, mb_fini_pack, zone_mbuf); 145 146 /* uma_prealloc() goes here */ 147 148 /* 149 * Hook event handler for low-memory situation, used to 150 * drain protocols and push data back to the caches (UMA 151 * later pushes it back to VM). 152 */ 153 EVENTHANDLER_REGISTER(vm_lowmem, mb_reclaim, NULL, 154 EVENTHANDLER_PRI_FIRST); 155 156 /* 157 * [Re]set counters and local statistics knobs. 158 * XXX Some of these should go and be replaced, but UMA stat 159 * gathering needs to be revised. 160 */ 161 mbstat.m_mbufs = 0; 162 mbstat.m_mclusts = 0; 163 mbstat.m_drain = 0; 164 mbstat.m_msize = MSIZE; 165 mbstat.m_mclbytes = MCLBYTES; 166 mbstat.m_minclsize = MINCLSIZE; 167 mbstat.m_mlen = MLEN; 168 mbstat.m_mhlen = MHLEN; 169 mbstat.m_numtypes = MT_NTYPES; 170 171 mbstat.m_mcfail = mbstat.m_mpfail = 0; 172 mbstat.sf_iocnt = 0; 173 mbstat.sf_allocwait = mbstat.sf_allocfail = 0; 174 } 175 176 /* 177 * Constructor for Mbuf master zone. 178 * 179 * The 'arg' pointer points to a mb_args structure which 180 * contains call-specific information required to support the 181 * mbuf allocation API. 182 */ 183 static int 184 mb_ctor_mbuf(void *mem, int size, void *arg, int how) 185 { 186 struct mbuf *m; 187 struct mb_args *args; 188 #ifdef MAC 189 int error; 190 #endif 191 int flags; 192 short type; 193 194 m = (struct mbuf *)mem; 195 args = (struct mb_args *)arg; 196 flags = args->flags; 197 type = args->type; 198 199 m->m_type = type; 200 m->m_next = NULL; 201 m->m_nextpkt = NULL; 202 m->m_flags = flags; 203 if (flags & M_PKTHDR) { 204 m->m_data = m->m_pktdat; 205 m->m_pkthdr.rcvif = NULL; 206 m->m_pkthdr.csum_flags = 0; 207 SLIST_INIT(&m->m_pkthdr.tags); 208 #ifdef MAC 209 /* If the label init fails, fail the alloc */ 210 error = mac_init_mbuf(m, how); 211 if (error) 212 return (error); 213 #endif 214 } else 215 m->m_data = m->m_dat; 216 mbstat.m_mbufs += 1; /* XXX */ 217 return (0); 218 } 219 220 /* 221 * The Mbuf master zone and Packet secondary zone destructor. 222 */ 223 static void 224 mb_dtor_mbuf(void *mem, int size, void *arg) 225 { 226 struct mbuf *m; 227 228 m = (struct mbuf *)mem; 229 if ((m->m_flags & M_PKTHDR) != 0) 230 m_tag_delete_chain(m, NULL); 231 mbstat.m_mbufs -= 1; /* XXX */ 232 } 233 234 /* XXX Only because of stats */ 235 static void 236 mb_dtor_pack(void *mem, int size, void *arg) 237 { 238 struct mbuf *m; 239 240 m = (struct mbuf *)mem; 241 if ((m->m_flags & M_PKTHDR) != 0) 242 m_tag_delete_chain(m, NULL); 243 mbstat.m_mbufs -= 1; /* XXX */ 244 mbstat.m_mclusts -= 1; /* XXX */ 245 } 246 247 /* 248 * The Cluster zone constructor. 249 * 250 * Here the 'arg' pointer points to the Mbuf which we 251 * are configuring cluster storage for. 252 */ 253 static int 254 mb_ctor_clust(void *mem, int size, void *arg, int how) 255 { 256 struct mbuf *m; 257 258 m = (struct mbuf *)arg; 259 m->m_ext.ext_buf = (caddr_t)mem; 260 m->m_data = m->m_ext.ext_buf; 261 m->m_flags |= M_EXT; 262 m->m_ext.ext_free = NULL; 263 m->m_ext.ext_args = NULL; 264 m->m_ext.ext_size = MCLBYTES; 265 m->m_ext.ext_type = EXT_CLUSTER; 266 m->m_ext.ref_cnt = (u_int *)uma_find_refcnt(zone_clust, 267 m->m_ext.ext_buf); 268 *(m->m_ext.ref_cnt) = 1; 269 mbstat.m_mclusts += 1; /* XXX */ 270 return (0); 271 } 272 273 /* XXX */ 274 static void 275 mb_dtor_clust(void *mem, int size, void *arg) 276 { 277 mbstat.m_mclusts -= 1; /* XXX */ 278 } 279 280 /* 281 * The Packet secondary zone's init routine, executed on the 282 * object's transition from keg slab to zone cache. 283 */ 284 static int 285 mb_init_pack(void *mem, int size, int how) 286 { 287 struct mbuf *m; 288 289 m = (struct mbuf *)mem; 290 m->m_ext.ext_buf = NULL; 291 uma_zalloc_arg(zone_clust, m, how); 292 if (m->m_ext.ext_buf == NULL) 293 return (ENOMEM); 294 mbstat.m_mclusts -= 1; /* XXX */ 295 return (0); 296 } 297 298 /* 299 * The Packet secondary zone's fini routine, executed on the 300 * object's transition from zone cache to keg slab. 301 */ 302 static void 303 mb_fini_pack(void *mem, int size) 304 { 305 struct mbuf *m; 306 307 m = (struct mbuf *)mem; 308 uma_zfree_arg(zone_clust, m->m_ext.ext_buf, NULL); 309 m->m_ext.ext_buf = NULL; 310 mbstat.m_mclusts += 1; /* XXX */ 311 } 312 313 /* 314 * The "packet" keg constructor. 315 */ 316 static int 317 mb_ctor_pack(void *mem, int size, void *arg, int how) 318 { 319 struct mbuf *m; 320 struct mb_args *args; 321 #ifdef MAC 322 int error; 323 #endif 324 int flags; 325 short type; 326 327 m = (struct mbuf *)mem; 328 args = (struct mb_args *)arg; 329 flags = args->flags; 330 type = args->type; 331 332 m->m_type = type; 333 m->m_next = NULL; 334 m->m_nextpkt = NULL; 335 m->m_data = m->m_ext.ext_buf; 336 m->m_flags = flags|M_EXT; 337 m->m_ext.ext_free = NULL; 338 m->m_ext.ext_args = NULL; 339 m->m_ext.ext_size = MCLBYTES; 340 m->m_ext.ext_type = EXT_PACKET; 341 *(m->m_ext.ref_cnt) = 1; 342 343 if (flags & M_PKTHDR) { 344 m->m_pkthdr.rcvif = NULL; 345 m->m_pkthdr.csum_flags = 0; 346 SLIST_INIT(&m->m_pkthdr.tags); 347 #ifdef MAC 348 /* If the label init fails, fail the alloc */ 349 error = mac_init_mbuf(m, how); 350 if (error) 351 return (error); 352 #endif 353 } 354 mbstat.m_mbufs += 1; /* XXX */ 355 mbstat.m_mclusts += 1; /* XXX */ 356 return (0); 357 } 358 359 /* 360 * This is the protocol drain routine. 361 * 362 * No locks should be held when this is called. The drain routines have to 363 * presently acquire some locks which raises the possibility of lock order 364 * reversal. 365 */ 366 static void 367 mb_reclaim(void *junk) 368 { 369 struct domain *dp; 370 struct protosw *pr; 371 372 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK | WARN_PANIC, NULL, 373 "mb_reclaim()"); 374 375 mbstat.m_drain++; 376 for (dp = domains; dp != NULL; dp = dp->dom_next) 377 for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++) 378 if (pr->pr_drain != NULL) 379 (*pr->pr_drain)(); 380 } 381