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 /* Ensure that MSIZE doesn't break dtom() - it must be a power of 2 */ 127 CTASSERT((((MSIZE - 1) ^ MSIZE) + 1) >> 1 == MSIZE); 128 129 /* 130 * Initialize FreeBSD Network buffer allocation. 131 */ 132 SYSINIT(mbuf, SI_SUB_MBUF, SI_ORDER_FIRST, mbuf_init, NULL) 133 static void 134 mbuf_init(void *dummy) 135 { 136 137 /* 138 * Configure UMA zones for Mbufs, Clusters, and Packets. 139 */ 140 zone_mbuf = uma_zcreate("Mbuf", MSIZE, mb_ctor_mbuf, mb_dtor_mbuf, 141 NULL, NULL, MSIZE - 1, UMA_ZONE_MAXBUCKET); 142 zone_clust = uma_zcreate("MbufClust", MCLBYTES, mb_ctor_clust, 143 mb_dtor_clust, NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_REFCNT); 144 if (nmbclusters > 0) 145 uma_zone_set_max(zone_clust, nmbclusters); 146 zone_pack = uma_zsecond_create("Packet", mb_ctor_pack, mb_dtor_pack, 147 mb_init_pack, mb_fini_pack, zone_mbuf); 148 149 /* uma_prealloc() goes here */ 150 151 /* 152 * Hook event handler for low-memory situation, used to 153 * drain protocols and push data back to the caches (UMA 154 * later pushes it back to VM). 155 */ 156 EVENTHANDLER_REGISTER(vm_lowmem, mb_reclaim, NULL, 157 EVENTHANDLER_PRI_FIRST); 158 159 /* 160 * [Re]set counters and local statistics knobs. 161 * XXX Some of these should go and be replaced, but UMA stat 162 * gathering needs to be revised. 163 */ 164 mbstat.m_mbufs = 0; 165 mbstat.m_mclusts = 0; 166 mbstat.m_drain = 0; 167 mbstat.m_msize = MSIZE; 168 mbstat.m_mclbytes = MCLBYTES; 169 mbstat.m_minclsize = MINCLSIZE; 170 mbstat.m_mlen = MLEN; 171 mbstat.m_mhlen = MHLEN; 172 mbstat.m_numtypes = MT_NTYPES; 173 174 mbstat.m_mcfail = mbstat.m_mpfail = 0; 175 mbstat.sf_iocnt = 0; 176 mbstat.sf_allocwait = mbstat.sf_allocfail = 0; 177 } 178 179 /* 180 * Constructor for Mbuf master zone. 181 * 182 * The 'arg' pointer points to a mb_args structure which 183 * contains call-specific information required to support the 184 * mbuf allocation API. 185 */ 186 static int 187 mb_ctor_mbuf(void *mem, int size, void *arg, int how) 188 { 189 struct mbuf *m; 190 struct mb_args *args; 191 #ifdef MAC 192 int error; 193 #endif 194 int flags; 195 short type; 196 197 m = (struct mbuf *)mem; 198 args = (struct mb_args *)arg; 199 flags = args->flags; 200 type = args->type; 201 202 m->m_type = type; 203 m->m_next = NULL; 204 m->m_nextpkt = NULL; 205 m->m_flags = flags; 206 if (flags & M_PKTHDR) { 207 m->m_data = m->m_pktdat; 208 m->m_pkthdr.rcvif = NULL; 209 m->m_pkthdr.csum_flags = 0; 210 SLIST_INIT(&m->m_pkthdr.tags); 211 #ifdef MAC 212 /* If the label init fails, fail the alloc */ 213 error = mac_init_mbuf(m, how); 214 if (error) 215 return (error); 216 #endif 217 } else 218 m->m_data = m->m_dat; 219 mbstat.m_mbufs += 1; /* XXX */ 220 return (0); 221 } 222 223 /* 224 * The Mbuf master zone and Packet secondary zone destructor. 225 */ 226 static void 227 mb_dtor_mbuf(void *mem, int size, void *arg) 228 { 229 struct mbuf *m; 230 231 m = (struct mbuf *)mem; 232 if ((m->m_flags & M_PKTHDR) != 0) 233 m_tag_delete_chain(m, NULL); 234 mbstat.m_mbufs -= 1; /* XXX */ 235 } 236 237 /* XXX Only because of stats */ 238 static void 239 mb_dtor_pack(void *mem, int size, void *arg) 240 { 241 struct mbuf *m; 242 243 m = (struct mbuf *)mem; 244 if ((m->m_flags & M_PKTHDR) != 0) 245 m_tag_delete_chain(m, NULL); 246 mbstat.m_mbufs -= 1; /* XXX */ 247 mbstat.m_mclusts -= 1; /* XXX */ 248 } 249 250 /* 251 * The Cluster zone constructor. 252 * 253 * Here the 'arg' pointer points to the Mbuf which we 254 * are configuring cluster storage for. 255 */ 256 static int 257 mb_ctor_clust(void *mem, int size, void *arg, int how) 258 { 259 struct mbuf *m; 260 261 m = (struct mbuf *)arg; 262 m->m_ext.ext_buf = (caddr_t)mem; 263 m->m_data = m->m_ext.ext_buf; 264 m->m_flags |= M_EXT; 265 m->m_ext.ext_free = NULL; 266 m->m_ext.ext_args = NULL; 267 m->m_ext.ext_size = MCLBYTES; 268 m->m_ext.ext_type = EXT_CLUSTER; 269 m->m_ext.ref_cnt = (u_int *)uma_find_refcnt(zone_clust, 270 m->m_ext.ext_buf); 271 *(m->m_ext.ref_cnt) = 1; 272 mbstat.m_mclusts += 1; /* XXX */ 273 return (0); 274 } 275 276 /* XXX */ 277 static void 278 mb_dtor_clust(void *mem, int size, void *arg) 279 { 280 mbstat.m_mclusts -= 1; /* XXX */ 281 } 282 283 /* 284 * The Packet secondary zone's init routine, executed on the 285 * object's transition from keg slab to zone cache. 286 */ 287 static int 288 mb_init_pack(void *mem, int size, int how) 289 { 290 struct mbuf *m; 291 292 m = (struct mbuf *)mem; 293 m->m_ext.ext_buf = NULL; 294 uma_zalloc_arg(zone_clust, m, how); 295 if (m->m_ext.ext_buf == NULL) 296 return (ENOMEM); 297 mbstat.m_mclusts -= 1; /* XXX */ 298 return (0); 299 } 300 301 /* 302 * The Packet secondary zone's fini routine, executed on the 303 * object's transition from zone cache to keg slab. 304 */ 305 static void 306 mb_fini_pack(void *mem, int size) 307 { 308 struct mbuf *m; 309 310 m = (struct mbuf *)mem; 311 uma_zfree_arg(zone_clust, m->m_ext.ext_buf, NULL); 312 m->m_ext.ext_buf = NULL; 313 mbstat.m_mclusts += 1; /* XXX */ 314 } 315 316 /* 317 * The "packet" keg constructor. 318 */ 319 static int 320 mb_ctor_pack(void *mem, int size, void *arg, int how) 321 { 322 struct mbuf *m; 323 struct mb_args *args; 324 #ifdef MAC 325 int error; 326 #endif 327 int flags; 328 short type; 329 330 m = (struct mbuf *)mem; 331 args = (struct mb_args *)arg; 332 flags = args->flags; 333 type = args->type; 334 335 m->m_type = type; 336 m->m_next = NULL; 337 m->m_nextpkt = NULL; 338 m->m_data = m->m_ext.ext_buf; 339 m->m_flags = flags|M_EXT; 340 m->m_ext.ext_free = NULL; 341 m->m_ext.ext_args = NULL; 342 m->m_ext.ext_size = MCLBYTES; 343 m->m_ext.ext_type = EXT_PACKET; 344 *(m->m_ext.ref_cnt) = 1; 345 346 if (flags & M_PKTHDR) { 347 m->m_pkthdr.rcvif = NULL; 348 m->m_pkthdr.csum_flags = 0; 349 SLIST_INIT(&m->m_pkthdr.tags); 350 #ifdef MAC 351 /* If the label init fails, fail the alloc */ 352 error = mac_init_mbuf(m, how); 353 if (error) 354 return (error); 355 #endif 356 } 357 mbstat.m_mbufs += 1; /* XXX */ 358 mbstat.m_mclusts += 1; /* XXX */ 359 return (0); 360 } 361 362 /* 363 * This is the protocol drain routine. 364 * 365 * No locks should be held when this is called. The drain routines have to 366 * presently acquire some locks which raises the possibility of lock order 367 * reversal. 368 */ 369 static void 370 mb_reclaim(void *junk) 371 { 372 struct domain *dp; 373 struct protosw *pr; 374 375 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK | WARN_PANIC, NULL, 376 "mb_reclaim()"); 377 378 mbstat.m_drain++; 379 for (dp = domains; dp != NULL; dp = dp->dom_next) 380 for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++) 381 if (pr->pr_drain != NULL) 382 (*pr->pr_drain)(); 383 } 384