| 1 | /* |
| 2 | * (MPSAFE) |
| 3 | * |
| 4 | * Copyright (c) 2004 Jeffrey M. Hsu. All rights reserved. |
| 5 | * Copyright (c) 2004 The DragonFly Project. All rights reserved. |
| 6 | * |
| 7 | * This code is derived from software contributed to The DragonFly Project |
| 8 | * by Jeffrey M. Hsu. |
| 9 | * |
| 10 | * Redistribution and use in source and binary forms, with or without |
| 11 | * modification, are permitted provided that the following conditions |
| 12 | * are met: |
| 13 | * 1. Redistributions of source code must retain the above copyright |
| 14 | * notice, this list of conditions and the following disclaimer. |
| 15 | * 2. Redistributions in binary form must reproduce the above copyright |
| 16 | * notice, this list of conditions and the following disclaimer in the |
| 17 | * documentation and/or other materials provided with the distribution. |
| 18 | * 3. Neither the name of The DragonFly Project nor the names of its |
| 19 | * contributors may be used to endorse or promote products derived |
| 20 | * from this software without specific, prior written permission. |
| 21 | * |
| 22 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| 23 | * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| 24 | * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS |
| 25 | * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE |
| 26 | * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, |
| 27 | * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING, |
| 28 | * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
| 29 | * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED |
| 30 | * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, |
| 31 | * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT |
| 32 | * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| 33 | * SUCH DAMAGE. |
| 34 | */ |
| 35 | |
| 36 | /* |
| 37 | * Copyright (c) 1982, 1986, 1988, 1991, 1993 |
| 38 | * The Regents of the University of California. All rights reserved. |
| 39 | * |
| 40 | * Redistribution and use in source and binary forms, with or without |
| 41 | * modification, are permitted provided that the following conditions |
| 42 | * are met: |
| 43 | * 1. Redistributions of source code must retain the above copyright |
| 44 | * notice, this list of conditions and the following disclaimer. |
| 45 | * 2. Redistributions in binary form must reproduce the above copyright |
| 46 | * notice, this list of conditions and the following disclaimer in the |
| 47 | * documentation and/or other materials provided with the distribution. |
| 48 | * 3. All advertising materials mentioning features or use of this software |
| 49 | * must display the following acknowledgement: |
| 50 | * This product includes software developed by the University of |
| 51 | * California, Berkeley and its contributors. |
| 52 | * 4. Neither the name of the University nor the names of its contributors |
| 53 | * may be used to endorse or promote products derived from this software |
| 54 | * without specific prior written permission. |
| 55 | * |
| 56 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
| 57 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| 58 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| 59 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
| 60 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| 61 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| 62 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| 63 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| 64 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| 65 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| 66 | * SUCH DAMAGE. |
| 67 | * |
| 68 | * @(#)uipc_mbuf.c 8.2 (Berkeley) 1/4/94 |
| 69 | * $FreeBSD: src/sys/kern/uipc_mbuf.c,v 1.51.2.24 2003/04/15 06:59:29 silby Exp $ |
| 70 | * $DragonFly: src/sys/kern/uipc_mbuf.c,v 1.70 2008/11/20 14:21:01 sephe Exp $ |
| 71 | */ |
| 72 | |
| 73 | #include "opt_param.h" |
| 74 | #include "opt_mbuf_stress_test.h" |
| 75 | #include <sys/param.h> |
| 76 | #include <sys/systm.h> |
| 77 | #include <sys/malloc.h> |
| 78 | #include <sys/mbuf.h> |
| 79 | #include <sys/kernel.h> |
| 80 | #include <sys/sysctl.h> |
| 81 | #include <sys/domain.h> |
| 82 | #include <sys/objcache.h> |
| 83 | #include <sys/tree.h> |
| 84 | #include <sys/protosw.h> |
| 85 | #include <sys/uio.h> |
| 86 | #include <sys/thread.h> |
| 87 | #include <sys/globaldata.h> |
| 88 | |
| 89 | #include <sys/thread2.h> |
| 90 | #include <sys/spinlock2.h> |
| 91 | |
| 92 | #include <machine/atomic.h> |
| 93 | #include <machine/limits.h> |
| 94 | |
| 95 | #include <vm/vm.h> |
| 96 | #include <vm/vm_kern.h> |
| 97 | #include <vm/vm_extern.h> |
| 98 | |
| 99 | #ifdef INVARIANTS |
| 100 | #include <machine/cpu.h> |
| 101 | #endif |
| 102 | |
| 103 | /* |
| 104 | * mbuf cluster meta-data |
| 105 | */ |
| 106 | struct mbcluster { |
| 107 | int32_t mcl_refs; |
| 108 | void *mcl_data; |
| 109 | }; |
| 110 | |
| 111 | /* |
| 112 | * mbuf tracking for debugging purposes |
| 113 | */ |
| 114 | #ifdef MBUF_DEBUG |
| 115 | |
| 116 | static MALLOC_DEFINE(M_MTRACK, "mtrack", "mtrack"); |
| 117 | |
| 118 | struct mbctrack; |
| 119 | RB_HEAD(mbuf_rb_tree, mbtrack); |
| 120 | RB_PROTOTYPE2(mbuf_rb_tree, mbtrack, rb_node, mbtrack_cmp, struct mbuf *); |
| 121 | |
| 122 | struct mbtrack { |
| 123 | RB_ENTRY(mbtrack) rb_node; |
| 124 | int trackid; |
| 125 | struct mbuf *m; |
| 126 | }; |
| 127 | |
| 128 | static int |
| 129 | mbtrack_cmp(struct mbtrack *mb1, struct mbtrack *mb2) |
| 130 | { |
| 131 | if (mb1->m < mb2->m) |
| 132 | return(-1); |
| 133 | if (mb1->m > mb2->m) |
| 134 | return(1); |
| 135 | return(0); |
| 136 | } |
| 137 | |
| 138 | RB_GENERATE2(mbuf_rb_tree, mbtrack, rb_node, mbtrack_cmp, struct mbuf *, m); |
| 139 | |
| 140 | struct mbuf_rb_tree mbuf_track_root; |
| 141 | static struct spinlock mbuf_track_spin = SPINLOCK_INITIALIZER(mbuf_track_spin); |
| 142 | |
| 143 | static void |
| 144 | mbuftrack(struct mbuf *m) |
| 145 | { |
| 146 | struct mbtrack *mbt; |
| 147 | |
| 148 | mbt = kmalloc(sizeof(*mbt), M_MTRACK, M_INTWAIT|M_ZERO); |
| 149 | spin_lock(&mbuf_track_spin); |
| 150 | mbt->m = m; |
| 151 | if (mbuf_rb_tree_RB_INSERT(&mbuf_track_root, mbt)) { |
| 152 | spin_unlock(&mbuf_track_spin); |
| 153 | panic("mbuftrack: mbuf %p already being tracked\n", m); |
| 154 | } |
| 155 | spin_unlock(&mbuf_track_spin); |
| 156 | } |
| 157 | |
| 158 | static void |
| 159 | mbufuntrack(struct mbuf *m) |
| 160 | { |
| 161 | struct mbtrack *mbt; |
| 162 | |
| 163 | spin_lock(&mbuf_track_spin); |
| 164 | mbt = mbuf_rb_tree_RB_LOOKUP(&mbuf_track_root, m); |
| 165 | if (mbt == NULL) { |
| 166 | spin_unlock(&mbuf_track_spin); |
| 167 | panic("mbufuntrack: mbuf %p was not tracked\n", m); |
| 168 | } else { |
| 169 | mbuf_rb_tree_RB_REMOVE(&mbuf_track_root, mbt); |
| 170 | kfree(mbt, M_MTRACK); |
| 171 | } |
| 172 | spin_unlock(&mbuf_track_spin); |
| 173 | } |
| 174 | |
| 175 | void |
| 176 | mbuftrackid(struct mbuf *m, int trackid) |
| 177 | { |
| 178 | struct mbtrack *mbt; |
| 179 | struct mbuf *n; |
| 180 | |
| 181 | spin_lock(&mbuf_track_spin); |
| 182 | while (m) { |
| 183 | n = m->m_nextpkt; |
| 184 | while (m) { |
| 185 | mbt = mbuf_rb_tree_RB_LOOKUP(&mbuf_track_root, m); |
| 186 | if (mbt == NULL) { |
| 187 | spin_unlock(&mbuf_track_spin); |
| 188 | panic("mbuftrackid: mbuf %p not tracked", m); |
| 189 | } |
| 190 | mbt->trackid = trackid; |
| 191 | m = m->m_next; |
| 192 | } |
| 193 | m = n; |
| 194 | } |
| 195 | spin_unlock(&mbuf_track_spin); |
| 196 | } |
| 197 | |
| 198 | static int |
| 199 | mbuftrack_callback(struct mbtrack *mbt, void *arg) |
| 200 | { |
| 201 | struct sysctl_req *req = arg; |
| 202 | char buf[64]; |
| 203 | int error; |
| 204 | |
| 205 | ksnprintf(buf, sizeof(buf), "mbuf %p track %d\n", mbt->m, mbt->trackid); |
| 206 | |
| 207 | spin_unlock(&mbuf_track_spin); |
| 208 | error = SYSCTL_OUT(req, buf, strlen(buf)); |
| 209 | spin_lock(&mbuf_track_spin); |
| 210 | if (error) |
| 211 | return(-error); |
| 212 | return(0); |
| 213 | } |
| 214 | |
| 215 | static int |
| 216 | mbuftrack_show(SYSCTL_HANDLER_ARGS) |
| 217 | { |
| 218 | int error; |
| 219 | |
| 220 | spin_lock(&mbuf_track_spin); |
| 221 | error = mbuf_rb_tree_RB_SCAN(&mbuf_track_root, NULL, |
| 222 | mbuftrack_callback, req); |
| 223 | spin_unlock(&mbuf_track_spin); |
| 224 | return (-error); |
| 225 | } |
| 226 | SYSCTL_PROC(_kern_ipc, OID_AUTO, showmbufs, CTLFLAG_RD|CTLTYPE_STRING, |
| 227 | 0, 0, mbuftrack_show, "A", "Show all in-use mbufs"); |
| 228 | |
| 229 | #else |
| 230 | |
| 231 | #define mbuftrack(m) |
| 232 | #define mbufuntrack(m) |
| 233 | |
| 234 | #endif |
| 235 | |
| 236 | static void mbinit(void *); |
| 237 | SYSINIT(mbuf, SI_BOOT2_MACHDEP, SI_ORDER_FIRST, mbinit, NULL) |
| 238 | |
| 239 | static u_long mbtypes[SMP_MAXCPU][MT_NTYPES]; |
| 240 | |
| 241 | static struct mbstat mbstat[SMP_MAXCPU]; |
| 242 | int max_linkhdr; |
| 243 | int max_protohdr; |
| 244 | int max_hdr; |
| 245 | int max_datalen; |
| 246 | int m_defragpackets; |
| 247 | int m_defragbytes; |
| 248 | int m_defraguseless; |
| 249 | int m_defragfailure; |
| 250 | #ifdef MBUF_STRESS_TEST |
| 251 | int m_defragrandomfailures; |
| 252 | #endif |
| 253 | |
| 254 | struct objcache *mbuf_cache, *mbufphdr_cache; |
| 255 | struct objcache *mclmeta_cache; |
| 256 | struct objcache *mbufcluster_cache, *mbufphdrcluster_cache; |
| 257 | |
| 258 | int nmbclusters; |
| 259 | int nmbufs; |
| 260 | |
| 261 | SYSCTL_INT(_kern_ipc, KIPC_MAX_LINKHDR, max_linkhdr, CTLFLAG_RW, |
| 262 | &max_linkhdr, 0, ""); |
| 263 | SYSCTL_INT(_kern_ipc, KIPC_MAX_PROTOHDR, max_protohdr, CTLFLAG_RW, |
| 264 | &max_protohdr, 0, ""); |
| 265 | SYSCTL_INT(_kern_ipc, KIPC_MAX_HDR, max_hdr, CTLFLAG_RW, &max_hdr, 0, ""); |
| 266 | SYSCTL_INT(_kern_ipc, KIPC_MAX_DATALEN, max_datalen, CTLFLAG_RW, |
| 267 | &max_datalen, 0, ""); |
| 268 | SYSCTL_INT(_kern_ipc, OID_AUTO, mbuf_wait, CTLFLAG_RW, |
| 269 | &mbuf_wait, 0, ""); |
| 270 | static int do_mbstat(SYSCTL_HANDLER_ARGS); |
| 271 | |
| 272 | SYSCTL_PROC(_kern_ipc, KIPC_MBSTAT, mbstat, CTLTYPE_STRUCT|CTLFLAG_RD, |
| 273 | 0, 0, do_mbstat, "S,mbstat", ""); |
| 274 | |
| 275 | static int do_mbtypes(SYSCTL_HANDLER_ARGS); |
| 276 | |
| 277 | SYSCTL_PROC(_kern_ipc, OID_AUTO, mbtypes, CTLTYPE_ULONG|CTLFLAG_RD, |
| 278 | 0, 0, do_mbtypes, "LU", ""); |
| 279 | |
| 280 | static int |
| 281 | do_mbstat(SYSCTL_HANDLER_ARGS) |
| 282 | { |
| 283 | struct mbstat mbstat_total; |
| 284 | struct mbstat *mbstat_totalp; |
| 285 | int i; |
| 286 | |
| 287 | bzero(&mbstat_total, sizeof(mbstat_total)); |
| 288 | mbstat_totalp = &mbstat_total; |
| 289 | |
| 290 | for (i = 0; i < ncpus; i++) |
| 291 | { |
| 292 | mbstat_total.m_mbufs += mbstat[i].m_mbufs; |
| 293 | mbstat_total.m_clusters += mbstat[i].m_clusters; |
| 294 | mbstat_total.m_spare += mbstat[i].m_spare; |
| 295 | mbstat_total.m_clfree += mbstat[i].m_clfree; |
| 296 | mbstat_total.m_drops += mbstat[i].m_drops; |
| 297 | mbstat_total.m_wait += mbstat[i].m_wait; |
| 298 | mbstat_total.m_drain += mbstat[i].m_drain; |
| 299 | mbstat_total.m_mcfail += mbstat[i].m_mcfail; |
| 300 | mbstat_total.m_mpfail += mbstat[i].m_mpfail; |
| 301 | |
| 302 | } |
| 303 | /* |
| 304 | * The following fields are not cumulative fields so just |
| 305 | * get their values once. |
| 306 | */ |
| 307 | mbstat_total.m_msize = mbstat[0].m_msize; |
| 308 | mbstat_total.m_mclbytes = mbstat[0].m_mclbytes; |
| 309 | mbstat_total.m_minclsize = mbstat[0].m_minclsize; |
| 310 | mbstat_total.m_mlen = mbstat[0].m_mlen; |
| 311 | mbstat_total.m_mhlen = mbstat[0].m_mhlen; |
| 312 | |
| 313 | return(sysctl_handle_opaque(oidp, mbstat_totalp, sizeof(mbstat_total), req)); |
| 314 | } |
| 315 | |
| 316 | static int |
| 317 | do_mbtypes(SYSCTL_HANDLER_ARGS) |
| 318 | { |
| 319 | u_long totals[MT_NTYPES]; |
| 320 | int i, j; |
| 321 | |
| 322 | for (i = 0; i < MT_NTYPES; i++) |
| 323 | totals[i] = 0; |
| 324 | |
| 325 | for (i = 0; i < ncpus; i++) |
| 326 | { |
| 327 | for (j = 0; j < MT_NTYPES; j++) |
| 328 | totals[j] += mbtypes[i][j]; |
| 329 | } |
| 330 | |
| 331 | return(sysctl_handle_opaque(oidp, totals, sizeof(totals), req)); |
| 332 | } |
| 333 | |
| 334 | /* |
| 335 | * These are read-only because we do not currently have any code |
| 336 | * to adjust the objcache limits after the fact. The variables |
| 337 | * may only be set as boot-time tunables. |
| 338 | */ |
| 339 | SYSCTL_INT(_kern_ipc, KIPC_NMBCLUSTERS, nmbclusters, CTLFLAG_RD, |
| 340 | &nmbclusters, 0, "Maximum number of mbuf clusters available"); |
| 341 | SYSCTL_INT(_kern_ipc, OID_AUTO, nmbufs, CTLFLAG_RD, &nmbufs, 0, |
| 342 | "Maximum number of mbufs available"); |
| 343 | |
| 344 | SYSCTL_INT(_kern_ipc, OID_AUTO, m_defragpackets, CTLFLAG_RD, |
| 345 | &m_defragpackets, 0, ""); |
| 346 | SYSCTL_INT(_kern_ipc, OID_AUTO, m_defragbytes, CTLFLAG_RD, |
| 347 | &m_defragbytes, 0, ""); |
| 348 | SYSCTL_INT(_kern_ipc, OID_AUTO, m_defraguseless, CTLFLAG_RD, |
| 349 | &m_defraguseless, 0, ""); |
| 350 | SYSCTL_INT(_kern_ipc, OID_AUTO, m_defragfailure, CTLFLAG_RD, |
| 351 | &m_defragfailure, 0, ""); |
| 352 | #ifdef MBUF_STRESS_TEST |
| 353 | SYSCTL_INT(_kern_ipc, OID_AUTO, m_defragrandomfailures, CTLFLAG_RW, |
| 354 | &m_defragrandomfailures, 0, ""); |
| 355 | #endif |
| 356 | |
| 357 | static MALLOC_DEFINE(M_MBUF, "mbuf", "mbuf"); |
| 358 | static MALLOC_DEFINE(M_MBUFCL, "mbufcl", "mbufcl"); |
| 359 | static MALLOC_DEFINE(M_MCLMETA, "mclmeta", "mclmeta"); |
| 360 | |
| 361 | static void m_reclaim (void); |
| 362 | static void m_mclref(void *arg); |
| 363 | static void m_mclfree(void *arg); |
| 364 | |
| 365 | #ifndef NMBCLUSTERS |
| 366 | #define NMBCLUSTERS (512 + maxusers * 16) |
| 367 | #endif |
| 368 | #ifndef NMBUFS |
| 369 | #define NMBUFS (nmbclusters * 2) |
| 370 | #endif |
| 371 | |
| 372 | /* |
| 373 | * Perform sanity checks of tunables declared above. |
| 374 | */ |
| 375 | static void |
| 376 | tunable_mbinit(void *dummy) |
| 377 | { |
| 378 | /* |
| 379 | * This has to be done before VM init. |
| 380 | */ |
| 381 | nmbclusters = NMBCLUSTERS; |
| 382 | TUNABLE_INT_FETCH("kern.ipc.nmbclusters", &nmbclusters); |
| 383 | nmbufs = NMBUFS; |
| 384 | TUNABLE_INT_FETCH("kern.ipc.nmbufs", &nmbufs); |
| 385 | /* Sanity checks */ |
| 386 | if (nmbufs < nmbclusters * 2) |
| 387 | nmbufs = nmbclusters * 2; |
| 388 | } |
| 389 | SYSINIT(tunable_mbinit, SI_BOOT1_TUNABLES, SI_ORDER_ANY, |
| 390 | tunable_mbinit, NULL); |
| 391 | |
| 392 | /* "number of clusters of pages" */ |
| 393 | #define NCL_INIT 1 |
| 394 | |
| 395 | #define NMB_INIT 16 |
| 396 | |
| 397 | /* |
| 398 | * The mbuf object cache only guarantees that m_next and m_nextpkt are |
| 399 | * NULL and that m_data points to the beginning of the data area. In |
| 400 | * particular, m_len and m_pkthdr.len are uninitialized. It is the |
| 401 | * responsibility of the caller to initialize those fields before use. |
| 402 | */ |
| 403 | |
| 404 | static boolean_t __inline |
| 405 | mbuf_ctor(void *obj, void *private, int ocflags) |
| 406 | { |
| 407 | struct mbuf *m = obj; |
| 408 | |
| 409 | m->m_next = NULL; |
| 410 | m->m_nextpkt = NULL; |
| 411 | m->m_data = m->m_dat; |
| 412 | m->m_flags = 0; |
| 413 | |
| 414 | return (TRUE); |
| 415 | } |
| 416 | |
| 417 | /* |
| 418 | * Initialize the mbuf and the packet header fields. |
| 419 | */ |
| 420 | static boolean_t |
| 421 | mbufphdr_ctor(void *obj, void *private, int ocflags) |
| 422 | { |
| 423 | struct mbuf *m = obj; |
| 424 | |
| 425 | m->m_next = NULL; |
| 426 | m->m_nextpkt = NULL; |
| 427 | m->m_data = m->m_pktdat; |
| 428 | m->m_flags = M_PKTHDR | M_PHCACHE; |
| 429 | |
| 430 | m->m_pkthdr.rcvif = NULL; /* eliminate XXX JH */ |
| 431 | SLIST_INIT(&m->m_pkthdr.tags); |
| 432 | m->m_pkthdr.csum_flags = 0; /* eliminate XXX JH */ |
| 433 | m->m_pkthdr.fw_flags = 0; /* eliminate XXX JH */ |
| 434 | |
| 435 | return (TRUE); |
| 436 | } |
| 437 | |
| 438 | /* |
| 439 | * A mbcluster object consists of 2K (MCLBYTES) cluster and a refcount. |
| 440 | */ |
| 441 | static boolean_t |
| 442 | mclmeta_ctor(void *obj, void *private, int ocflags) |
| 443 | { |
| 444 | struct mbcluster *cl = obj; |
| 445 | void *buf; |
| 446 | |
| 447 | if (ocflags & M_NOWAIT) |
| 448 | buf = kmalloc(MCLBYTES, M_MBUFCL, M_NOWAIT | M_ZERO); |
| 449 | else |
| 450 | buf = kmalloc(MCLBYTES, M_MBUFCL, M_INTWAIT | M_ZERO); |
| 451 | if (buf == NULL) |
| 452 | return (FALSE); |
| 453 | cl->mcl_refs = 0; |
| 454 | cl->mcl_data = buf; |
| 455 | return (TRUE); |
| 456 | } |
| 457 | |
| 458 | static void |
| 459 | mclmeta_dtor(void *obj, void *private) |
| 460 | { |
| 461 | struct mbcluster *mcl = obj; |
| 462 | |
| 463 | KKASSERT(mcl->mcl_refs == 0); |
| 464 | kfree(mcl->mcl_data, M_MBUFCL); |
| 465 | } |
| 466 | |
| 467 | static void |
| 468 | linkcluster(struct mbuf *m, struct mbcluster *cl) |
| 469 | { |
| 470 | /* |
| 471 | * Add the cluster to the mbuf. The caller will detect that the |
| 472 | * mbuf now has an attached cluster. |
| 473 | */ |
| 474 | m->m_ext.ext_arg = cl; |
| 475 | m->m_ext.ext_buf = cl->mcl_data; |
| 476 | m->m_ext.ext_ref = m_mclref; |
| 477 | m->m_ext.ext_free = m_mclfree; |
| 478 | m->m_ext.ext_size = MCLBYTES; |
| 479 | atomic_add_int(&cl->mcl_refs, 1); |
| 480 | |
| 481 | m->m_data = m->m_ext.ext_buf; |
| 482 | m->m_flags |= M_EXT | M_EXT_CLUSTER; |
| 483 | } |
| 484 | |
| 485 | static boolean_t |
| 486 | mbufphdrcluster_ctor(void *obj, void *private, int ocflags) |
| 487 | { |
| 488 | struct mbuf *m = obj; |
| 489 | struct mbcluster *cl; |
| 490 | |
| 491 | mbufphdr_ctor(obj, private, ocflags); |
| 492 | cl = objcache_get(mclmeta_cache, ocflags); |
| 493 | if (cl == NULL) { |
| 494 | ++mbstat[mycpu->gd_cpuid].m_drops; |
| 495 | return (FALSE); |
| 496 | } |
| 497 | m->m_flags |= M_CLCACHE; |
| 498 | linkcluster(m, cl); |
| 499 | return (TRUE); |
| 500 | } |
| 501 | |
| 502 | static boolean_t |
| 503 | mbufcluster_ctor(void *obj, void *private, int ocflags) |
| 504 | { |
| 505 | struct mbuf *m = obj; |
| 506 | struct mbcluster *cl; |
| 507 | |
| 508 | mbuf_ctor(obj, private, ocflags); |
| 509 | cl = objcache_get(mclmeta_cache, ocflags); |
| 510 | if (cl == NULL) { |
| 511 | ++mbstat[mycpu->gd_cpuid].m_drops; |
| 512 | return (FALSE); |
| 513 | } |
| 514 | m->m_flags |= M_CLCACHE; |
| 515 | linkcluster(m, cl); |
| 516 | return (TRUE); |
| 517 | } |
| 518 | |
| 519 | /* |
| 520 | * Used for both the cluster and cluster PHDR caches. |
| 521 | * |
| 522 | * The mbuf may have lost its cluster due to sharing, deal |
| 523 | * with the situation by checking M_EXT. |
| 524 | */ |
| 525 | static void |
| 526 | mbufcluster_dtor(void *obj, void *private) |
| 527 | { |
| 528 | struct mbuf *m = obj; |
| 529 | struct mbcluster *mcl; |
| 530 | |
| 531 | if (m->m_flags & M_EXT) { |
| 532 | KKASSERT((m->m_flags & M_EXT_CLUSTER) != 0); |
| 533 | mcl = m->m_ext.ext_arg; |
| 534 | KKASSERT(mcl->mcl_refs == 1); |
| 535 | mcl->mcl_refs = 0; |
| 536 | objcache_put(mclmeta_cache, mcl); |
| 537 | } |
| 538 | } |
| 539 | |
| 540 | struct objcache_malloc_args mbuf_malloc_args = { MSIZE, M_MBUF }; |
| 541 | struct objcache_malloc_args mclmeta_malloc_args = |
| 542 | { sizeof(struct mbcluster), M_MCLMETA }; |
| 543 | |
| 544 | /* ARGSUSED*/ |
| 545 | static void |
| 546 | mbinit(void *dummy) |
| 547 | { |
| 548 | int mb_limit, cl_limit; |
| 549 | int limit; |
| 550 | int i; |
| 551 | |
| 552 | /* |
| 553 | * Initialize statistics |
| 554 | */ |
| 555 | for (i = 0; i < ncpus; i++) { |
| 556 | atomic_set_long_nonlocked(&mbstat[i].m_msize, MSIZE); |
| 557 | atomic_set_long_nonlocked(&mbstat[i].m_mclbytes, MCLBYTES); |
| 558 | atomic_set_long_nonlocked(&mbstat[i].m_minclsize, MINCLSIZE); |
| 559 | atomic_set_long_nonlocked(&mbstat[i].m_mlen, MLEN); |
| 560 | atomic_set_long_nonlocked(&mbstat[i].m_mhlen, MHLEN); |
| 561 | } |
| 562 | |
| 563 | /* |
| 564 | * Create objtect caches and save cluster limits, which will |
| 565 | * be used to adjust backing kmalloc pools' limit later. |
| 566 | */ |
| 567 | |
| 568 | mb_limit = cl_limit = 0; |
| 569 | |
| 570 | limit = nmbufs; |
| 571 | mbuf_cache = objcache_create("mbuf", &limit, 0, |
| 572 | mbuf_ctor, NULL, NULL, |
| 573 | objcache_malloc_alloc, objcache_malloc_free, &mbuf_malloc_args); |
| 574 | mb_limit += limit; |
| 575 | |
| 576 | limit = nmbufs; |
| 577 | mbufphdr_cache = objcache_create("mbuf pkt hdr", &limit, 64, |
| 578 | mbufphdr_ctor, NULL, NULL, |
| 579 | objcache_malloc_alloc, objcache_malloc_free, &mbuf_malloc_args); |
| 580 | mb_limit += limit; |
| 581 | |
| 582 | cl_limit = nmbclusters; |
| 583 | mclmeta_cache = objcache_create("cluster mbuf", &cl_limit, 0, |
| 584 | mclmeta_ctor, mclmeta_dtor, NULL, |
| 585 | objcache_malloc_alloc, objcache_malloc_free, &mclmeta_malloc_args); |
| 586 | |
| 587 | limit = nmbclusters; |
| 588 | mbufcluster_cache = objcache_create("mbuf + cluster", &limit, 0, |
| 589 | mbufcluster_ctor, mbufcluster_dtor, NULL, |
| 590 | objcache_malloc_alloc, objcache_malloc_free, &mbuf_malloc_args); |
| 591 | mb_limit += limit; |
| 592 | |
| 593 | limit = nmbclusters; |
| 594 | mbufphdrcluster_cache = objcache_create("mbuf pkt hdr + cluster", |
| 595 | &limit, 64, mbufphdrcluster_ctor, mbufcluster_dtor, NULL, |
| 596 | objcache_malloc_alloc, objcache_malloc_free, &mbuf_malloc_args); |
| 597 | mb_limit += limit; |
| 598 | |
| 599 | /* |
| 600 | * Adjust backing kmalloc pools' limit |
| 601 | * |
| 602 | * NOTE: We raise the limit by another 1/8 to take the effect |
| 603 | * of loosememuse into account. |
| 604 | */ |
| 605 | cl_limit += cl_limit / 8; |
| 606 | kmalloc_raise_limit(mclmeta_malloc_args.mtype, |
| 607 | mclmeta_malloc_args.objsize * cl_limit); |
| 608 | kmalloc_raise_limit(M_MBUFCL, MCLBYTES * cl_limit); |
| 609 | |
| 610 | mb_limit += mb_limit / 8; |
| 611 | kmalloc_raise_limit(mbuf_malloc_args.mtype, |
| 612 | mbuf_malloc_args.objsize * mb_limit); |
| 613 | } |
| 614 | |
| 615 | /* |
| 616 | * Return the number of references to this mbuf's data. 0 is returned |
| 617 | * if the mbuf is not M_EXT, a reference count is returned if it is |
| 618 | * M_EXT | M_EXT_CLUSTER, and 99 is returned if it is a special M_EXT. |
| 619 | */ |
| 620 | int |
| 621 | m_sharecount(struct mbuf *m) |
| 622 | { |
| 623 | switch (m->m_flags & (M_EXT | M_EXT_CLUSTER)) { |
| 624 | case 0: |
| 625 | return (0); |
| 626 | case M_EXT: |
| 627 | return (99); |
| 628 | case M_EXT | M_EXT_CLUSTER: |
| 629 | return (((struct mbcluster *)m->m_ext.ext_arg)->mcl_refs); |
| 630 | } |
| 631 | /* NOTREACHED */ |
| 632 | return (0); /* to shut up compiler */ |
| 633 | } |
| 634 | |
| 635 | /* |
| 636 | * change mbuf to new type |
| 637 | */ |
| 638 | void |
| 639 | m_chtype(struct mbuf *m, int type) |
| 640 | { |
| 641 | struct globaldata *gd = mycpu; |
| 642 | |
| 643 | atomic_add_long_nonlocked(&mbtypes[gd->gd_cpuid][type], 1); |
| 644 | atomic_subtract_long_nonlocked(&mbtypes[gd->gd_cpuid][m->m_type], 1); |
| 645 | atomic_set_short_nonlocked(&m->m_type, type); |
| 646 | } |
| 647 | |
| 648 | static void |
| 649 | m_reclaim(void) |
| 650 | { |
| 651 | struct domain *dp; |
| 652 | struct protosw *pr; |
| 653 | |
| 654 | kprintf("Debug: m_reclaim() called\n"); |
| 655 | |
| 656 | SLIST_FOREACH(dp, &domains, dom_next) { |
| 657 | for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++) { |
| 658 | if (pr->pr_drain) |
| 659 | (*pr->pr_drain)(); |
| 660 | } |
| 661 | } |
| 662 | atomic_add_long_nonlocked(&mbstat[mycpu->gd_cpuid].m_drain, 1); |
| 663 | } |
| 664 | |
| 665 | static void __inline |
| 666 | updatestats(struct mbuf *m, int type) |
| 667 | { |
| 668 | struct globaldata *gd = mycpu; |
| 669 | m->m_type = type; |
| 670 | |
| 671 | mbuftrack(m); |
| 672 | |
| 673 | atomic_add_long_nonlocked(&mbtypes[gd->gd_cpuid][type], 1); |
| 674 | atomic_add_long_nonlocked(&mbstat[mycpu->gd_cpuid].m_mbufs, 1); |
| 675 | |
| 676 | } |
| 677 | |
| 678 | /* |
| 679 | * Allocate an mbuf. |
| 680 | */ |
| 681 | struct mbuf * |
| 682 | m_get(int how, int type) |
| 683 | { |
| 684 | struct mbuf *m; |
| 685 | int ntries = 0; |
| 686 | int ocf = MBTOM(how); |
| 687 | |
| 688 | retryonce: |
| 689 | |
| 690 | m = objcache_get(mbuf_cache, ocf); |
| 691 | |
| 692 | if (m == NULL) { |
| 693 | if ((how & MB_TRYWAIT) && ntries++ == 0) { |
| 694 | struct objcache *reclaimlist[] = { |
| 695 | mbufphdr_cache, |
| 696 | mbufcluster_cache, |
| 697 | mbufphdrcluster_cache |
| 698 | }; |
| 699 | const int nreclaims = __arysize(reclaimlist); |
| 700 | |
| 701 | if (!objcache_reclaimlist(reclaimlist, nreclaims, ocf)) |
| 702 | m_reclaim(); |
| 703 | goto retryonce; |
| 704 | } |
| 705 | ++mbstat[mycpu->gd_cpuid].m_drops; |
| 706 | return (NULL); |
| 707 | } |
| 708 | |
| 709 | updatestats(m, type); |
| 710 | return (m); |
| 711 | } |
| 712 | |
| 713 | struct mbuf * |
| 714 | m_gethdr(int how, int type) |
| 715 | { |
| 716 | struct mbuf *m; |
| 717 | int ocf = MBTOM(how); |
| 718 | int ntries = 0; |
| 719 | |
| 720 | retryonce: |
| 721 | |
| 722 | m = objcache_get(mbufphdr_cache, ocf); |
| 723 | |
| 724 | if (m == NULL) { |
| 725 | if ((how & MB_TRYWAIT) && ntries++ == 0) { |
| 726 | struct objcache *reclaimlist[] = { |
| 727 | mbuf_cache, |
| 728 | mbufcluster_cache, mbufphdrcluster_cache |
| 729 | }; |
| 730 | const int nreclaims = __arysize(reclaimlist); |
| 731 | |
| 732 | if (!objcache_reclaimlist(reclaimlist, nreclaims, ocf)) |
| 733 | m_reclaim(); |
| 734 | goto retryonce; |
| 735 | } |
| 736 | ++mbstat[mycpu->gd_cpuid].m_drops; |
| 737 | return (NULL); |
| 738 | } |
| 739 | |
| 740 | updatestats(m, type); |
| 741 | return (m); |
| 742 | } |
| 743 | |
| 744 | /* |
| 745 | * Get a mbuf (not a mbuf cluster!) and zero it. |
| 746 | * Deprecated. |
| 747 | */ |
| 748 | struct mbuf * |
| 749 | m_getclr(int how, int type) |
| 750 | { |
| 751 | struct mbuf *m; |
| 752 | |
| 753 | m = m_get(how, type); |
| 754 | if (m != NULL) |
| 755 | bzero(m->m_data, MLEN); |
| 756 | return (m); |
| 757 | } |
| 758 | |
| 759 | /* |
| 760 | * Returns an mbuf with an attached cluster. |
| 761 | * Because many network drivers use this kind of buffers a lot, it is |
| 762 | * convenient to keep a small pool of free buffers of this kind. |
| 763 | * Even a small size such as 10 gives about 10% improvement in the |
| 764 | * forwarding rate in a bridge or router. |
| 765 | */ |
| 766 | struct mbuf * |
| 767 | m_getcl(int how, short type, int flags) |
| 768 | { |
| 769 | struct mbuf *m; |
| 770 | int ocflags = MBTOM(how); |
| 771 | int ntries = 0; |
| 772 | |
| 773 | retryonce: |
| 774 | |
| 775 | if (flags & M_PKTHDR) |
| 776 | m = objcache_get(mbufphdrcluster_cache, ocflags); |
| 777 | else |
| 778 | m = objcache_get(mbufcluster_cache, ocflags); |
| 779 | |
| 780 | if (m == NULL) { |
| 781 | if ((how & MB_TRYWAIT) && ntries++ == 0) { |
| 782 | struct objcache *reclaimlist[1]; |
| 783 | |
| 784 | if (flags & M_PKTHDR) |
| 785 | reclaimlist[0] = mbufcluster_cache; |
| 786 | else |
| 787 | reclaimlist[0] = mbufphdrcluster_cache; |
| 788 | if (!objcache_reclaimlist(reclaimlist, 1, ocflags)) |
| 789 | m_reclaim(); |
| 790 | goto retryonce; |
| 791 | } |
| 792 | ++mbstat[mycpu->gd_cpuid].m_drops; |
| 793 | return (NULL); |
| 794 | } |
| 795 | |
| 796 | m->m_type = type; |
| 797 | |
| 798 | mbuftrack(m); |
| 799 | |
| 800 | atomic_add_long_nonlocked(&mbtypes[mycpu->gd_cpuid][type], 1); |
| 801 | atomic_add_long_nonlocked(&mbstat[mycpu->gd_cpuid].m_clusters, 1); |
| 802 | return (m); |
| 803 | } |
| 804 | |
| 805 | /* |
| 806 | * Allocate chain of requested length. |
| 807 | */ |
| 808 | struct mbuf * |
| 809 | m_getc(int len, int how, int type) |
| 810 | { |
| 811 | struct mbuf *n, *nfirst = NULL, **ntail = &nfirst; |
| 812 | int nsize; |
| 813 | |
| 814 | while (len > 0) { |
| 815 | n = m_getl(len, how, type, 0, &nsize); |
| 816 | if (n == NULL) |
| 817 | goto failed; |
| 818 | n->m_len = 0; |
| 819 | *ntail = n; |
| 820 | ntail = &n->m_next; |
| 821 | len -= nsize; |
| 822 | } |
| 823 | return (nfirst); |
| 824 | |
| 825 | failed: |
| 826 | m_freem(nfirst); |
| 827 | return (NULL); |
| 828 | } |
| 829 | |
| 830 | /* |
| 831 | * Allocate len-worth of mbufs and/or mbuf clusters (whatever fits best) |
| 832 | * and return a pointer to the head of the allocated chain. If m0 is |
| 833 | * non-null, then we assume that it is a single mbuf or an mbuf chain to |
| 834 | * which we want len bytes worth of mbufs and/or clusters attached, and so |
| 835 | * if we succeed in allocating it, we will just return a pointer to m0. |
| 836 | * |
| 837 | * If we happen to fail at any point during the allocation, we will free |
| 838 | * up everything we have already allocated and return NULL. |
| 839 | * |
| 840 | * Deprecated. Use m_getc() and m_cat() instead. |
| 841 | */ |
| 842 | struct mbuf * |
| 843 | m_getm(struct mbuf *m0, int len, int type, int how) |
| 844 | { |
| 845 | struct mbuf *nfirst; |
| 846 | |
| 847 | nfirst = m_getc(len, how, type); |
| 848 | |
| 849 | if (m0 != NULL) { |
| 850 | m_last(m0)->m_next = nfirst; |
| 851 | return (m0); |
| 852 | } |
| 853 | |
| 854 | return (nfirst); |
| 855 | } |
| 856 | |
| 857 | /* |
| 858 | * Adds a cluster to a normal mbuf, M_EXT is set on success. |
| 859 | * Deprecated. Use m_getcl() instead. |
| 860 | */ |
| 861 | void |
| 862 | m_mclget(struct mbuf *m, int how) |
| 863 | { |
| 864 | struct mbcluster *mcl; |
| 865 | |
| 866 | KKASSERT((m->m_flags & M_EXT) == 0); |
| 867 | mcl = objcache_get(mclmeta_cache, MBTOM(how)); |
| 868 | if (mcl != NULL) { |
| 869 | linkcluster(m, mcl); |
| 870 | atomic_add_long_nonlocked(&mbstat[mycpu->gd_cpuid].m_clusters, |
| 871 | 1); |
| 872 | } else { |
| 873 | ++mbstat[mycpu->gd_cpuid].m_drops; |
| 874 | } |
| 875 | } |
| 876 | |
| 877 | /* |
| 878 | * Updates to mbcluster must be MPSAFE. Only an entity which already has |
| 879 | * a reference to the cluster can ref it, so we are in no danger of |
| 880 | * racing an add with a subtract. But the operation must still be atomic |
| 881 | * since multiple entities may have a reference on the cluster. |
| 882 | * |
| 883 | * m_mclfree() is almost the same but it must contend with two entities |
| 884 | * freeing the cluster at the same time. |
| 885 | */ |
| 886 | static void |
| 887 | m_mclref(void *arg) |
| 888 | { |
| 889 | struct mbcluster *mcl = arg; |
| 890 | |
| 891 | atomic_add_int(&mcl->mcl_refs, 1); |
| 892 | } |
| 893 | |
| 894 | /* |
| 895 | * When dereferencing a cluster we have to deal with a N->0 race, where |
| 896 | * N entities free their references simultaniously. To do this we use |
| 897 | * atomic_fetchadd_int(). |
| 898 | */ |
| 899 | static void |
| 900 | m_mclfree(void *arg) |
| 901 | { |
| 902 | struct mbcluster *mcl = arg; |
| 903 | |
| 904 | if (atomic_fetchadd_int(&mcl->mcl_refs, -1) == 1) |
| 905 | objcache_put(mclmeta_cache, mcl); |
| 906 | } |
| 907 | |
| 908 | /* |
| 909 | * Free a single mbuf and any associated external storage. The successor, |
| 910 | * if any, is returned. |
| 911 | * |
| 912 | * We do need to check non-first mbuf for m_aux, since some of existing |
| 913 | * code does not call M_PREPEND properly. |
| 914 | * (example: call to bpf_mtap from drivers) |
| 915 | */ |
| 916 | struct mbuf * |
| 917 | m_free(struct mbuf *m) |
| 918 | { |
| 919 | struct mbuf *n; |
| 920 | struct globaldata *gd = mycpu; |
| 921 | |
| 922 | KASSERT(m->m_type != MT_FREE, ("freeing free mbuf %p", m)); |
| 923 | atomic_subtract_long_nonlocked(&mbtypes[gd->gd_cpuid][m->m_type], 1); |
| 924 | |
| 925 | n = m->m_next; |
| 926 | |
| 927 | /* |
| 928 | * Make sure the mbuf is in constructed state before returning it |
| 929 | * to the objcache. |
| 930 | */ |
| 931 | m->m_next = NULL; |
| 932 | mbufuntrack(m); |
| 933 | #ifdef notyet |
| 934 | KKASSERT(m->m_nextpkt == NULL); |
| 935 | #else |
| 936 | if (m->m_nextpkt != NULL) { |
| 937 | static int afewtimes = 10; |
| 938 | |
| 939 | if (afewtimes-- > 0) { |
| 940 | kprintf("mfree: m->m_nextpkt != NULL\n"); |
| 941 | print_backtrace(-1); |
| 942 | } |
| 943 | m->m_nextpkt = NULL; |
| 944 | } |
| 945 | #endif |
| 946 | if (m->m_flags & M_PKTHDR) { |
| 947 | m_tag_delete_chain(m); /* eliminate XXX JH */ |
| 948 | } |
| 949 | |
| 950 | m->m_flags &= (M_EXT | M_EXT_CLUSTER | M_CLCACHE | M_PHCACHE); |
| 951 | |
| 952 | /* |
| 953 | * Clean the M_PKTHDR state so we can return the mbuf to its original |
| 954 | * cache. This is based on the PHCACHE flag which tells us whether |
| 955 | * the mbuf was originally allocated out of a packet-header cache |
| 956 | * or a non-packet-header cache. |
| 957 | */ |
| 958 | if (m->m_flags & M_PHCACHE) { |
| 959 | m->m_flags |= M_PKTHDR; |
| 960 | m->m_pkthdr.rcvif = NULL; /* eliminate XXX JH */ |
| 961 | m->m_pkthdr.csum_flags = 0; /* eliminate XXX JH */ |
| 962 | m->m_pkthdr.fw_flags = 0; /* eliminate XXX JH */ |
| 963 | SLIST_INIT(&m->m_pkthdr.tags); |
| 964 | } |
| 965 | |
| 966 | /* |
| 967 | * Handle remaining flags combinations. M_CLCACHE tells us whether |
| 968 | * the mbuf was originally allocated from a cluster cache or not, |
| 969 | * and is totally separate from whether the mbuf is currently |
| 970 | * associated with a cluster. |
| 971 | */ |
| 972 | switch(m->m_flags & (M_CLCACHE | M_EXT | M_EXT_CLUSTER)) { |
| 973 | case M_CLCACHE | M_EXT | M_EXT_CLUSTER: |
| 974 | /* |
| 975 | * mbuf+cluster cache case. The mbuf was allocated from the |
| 976 | * combined mbuf_cluster cache and can be returned to the |
| 977 | * cache if the cluster hasn't been shared. |
| 978 | */ |
| 979 | if (m_sharecount(m) == 1) { |
| 980 | /* |
| 981 | * The cluster has not been shared, we can just |
| 982 | * reset the data pointer and return the mbuf |
| 983 | * to the cluster cache. Note that the reference |
| 984 | * count is left intact (it is still associated with |
| 985 | * an mbuf). |
| 986 | */ |
| 987 | m->m_data = m->m_ext.ext_buf; |
| 988 | if (m->m_flags & M_PHCACHE) |
| 989 | objcache_put(mbufphdrcluster_cache, m); |
| 990 | else |
| 991 | objcache_put(mbufcluster_cache, m); |
| 992 | atomic_subtract_long_nonlocked(&mbstat[mycpu->gd_cpuid].m_clusters, 1); |
| 993 | } else { |
| 994 | /* |
| 995 | * Hell. Someone else has a ref on this cluster, |
| 996 | * we have to disconnect it which means we can't |
| 997 | * put it back into the mbufcluster_cache, we |
| 998 | * have to destroy the mbuf. |
| 999 | * |
| 1000 | * Other mbuf references to the cluster will typically |
| 1001 | * be M_EXT | M_EXT_CLUSTER but without M_CLCACHE. |
| 1002 | * |
| 1003 | * XXX we could try to connect another cluster to |
| 1004 | * it. |
| 1005 | */ |
| 1006 | m->m_ext.ext_free(m->m_ext.ext_arg); |
| 1007 | m->m_flags &= ~(M_EXT | M_EXT_CLUSTER); |
| 1008 | if (m->m_flags & M_PHCACHE) |
| 1009 | objcache_dtor(mbufphdrcluster_cache, m); |
| 1010 | else |
| 1011 | objcache_dtor(mbufcluster_cache, m); |
| 1012 | } |
| 1013 | break; |
| 1014 | case M_EXT | M_EXT_CLUSTER: |
| 1015 | /* |
| 1016 | * Normal cluster associated with an mbuf that was allocated |
| 1017 | * from the normal mbuf pool rather then the cluster pool. |
| 1018 | * The cluster has to be independantly disassociated from the |
| 1019 | * mbuf. |
| 1020 | */ |
| 1021 | if (m_sharecount(m) == 1) |
| 1022 | atomic_subtract_long_nonlocked(&mbstat[mycpu->gd_cpuid].m_clusters, 1); |
| 1023 | /* fall through */ |
| 1024 | case M_EXT: |
| 1025 | /* |
| 1026 | * Normal cluster association case, disconnect the cluster from |
| 1027 | * the mbuf. The cluster may or may not be custom. |
| 1028 | */ |
| 1029 | m->m_ext.ext_free(m->m_ext.ext_arg); |
| 1030 | m->m_flags &= ~(M_EXT | M_EXT_CLUSTER); |
| 1031 | /* fall through */ |
| 1032 | case 0: |
| 1033 | /* |
| 1034 | * return the mbuf to the mbuf cache. |
| 1035 | */ |
| 1036 | if (m->m_flags & M_PHCACHE) { |
| 1037 | m->m_data = m->m_pktdat; |
| 1038 | objcache_put(mbufphdr_cache, m); |
| 1039 | } else { |
| 1040 | m->m_data = m->m_dat; |
| 1041 | objcache_put(mbuf_cache, m); |
| 1042 | } |
| 1043 | atomic_subtract_long_nonlocked(&mbstat[mycpu->gd_cpuid].m_mbufs, 1); |
| 1044 | break; |
| 1045 | default: |
| 1046 | if (!panicstr) |
| 1047 | panic("bad mbuf flags %p %08x\n", m, m->m_flags); |
| 1048 | break; |
| 1049 | } |
| 1050 | return (n); |
| 1051 | } |
| 1052 | |
| 1053 | void |
| 1054 | m_freem(struct mbuf *m) |
| 1055 | { |
| 1056 | while (m) |
| 1057 | m = m_free(m); |
| 1058 | } |
| 1059 | |
| 1060 | /* |
| 1061 | * mbuf utility routines |
| 1062 | */ |
| 1063 | |
| 1064 | /* |
| 1065 | * Lesser-used path for M_PREPEND: allocate new mbuf to prepend to chain and |
| 1066 | * copy junk along. |
| 1067 | */ |
| 1068 | struct mbuf * |
| 1069 | m_prepend(struct mbuf *m, int len, int how) |
| 1070 | { |
| 1071 | struct mbuf *mn; |
| 1072 | |
| 1073 | if (m->m_flags & M_PKTHDR) |
| 1074 | mn = m_gethdr(how, m->m_type); |
| 1075 | else |
| 1076 | mn = m_get(how, m->m_type); |
| 1077 | if (mn == NULL) { |
| 1078 | m_freem(m); |
| 1079 | return (NULL); |
| 1080 | } |
| 1081 | if (m->m_flags & M_PKTHDR) |
| 1082 | M_MOVE_PKTHDR(mn, m); |
| 1083 | mn->m_next = m; |
| 1084 | m = mn; |
| 1085 | if (len < MHLEN) |
| 1086 | MH_ALIGN(m, len); |
| 1087 | m->m_len = len; |
| 1088 | return (m); |
| 1089 | } |
| 1090 | |
| 1091 | /* |
| 1092 | * Make a copy of an mbuf chain starting "off0" bytes from the beginning, |
| 1093 | * continuing for "len" bytes. If len is M_COPYALL, copy to end of mbuf. |
| 1094 | * The wait parameter is a choice of MB_WAIT/MB_DONTWAIT from caller. |
| 1095 | * Note that the copy is read-only, because clusters are not copied, |
| 1096 | * only their reference counts are incremented. |
| 1097 | */ |
| 1098 | struct mbuf * |
| 1099 | m_copym(const struct mbuf *m, int off0, int len, int wait) |
| 1100 | { |
| 1101 | struct mbuf *n, **np; |
| 1102 | int off = off0; |
| 1103 | struct mbuf *top; |
| 1104 | int copyhdr = 0; |
| 1105 | |
| 1106 | KASSERT(off >= 0, ("m_copym, negative off %d", off)); |
| 1107 | KASSERT(len >= 0, ("m_copym, negative len %d", len)); |
| 1108 | if (off == 0 && (m->m_flags & M_PKTHDR)) |
| 1109 | copyhdr = 1; |
| 1110 | while (off > 0) { |
| 1111 | KASSERT(m != NULL, ("m_copym, offset > size of mbuf chain")); |
| 1112 | if (off < m->m_len) |
| 1113 | break; |
| 1114 | off -= m->m_len; |
| 1115 | m = m->m_next; |
| 1116 | } |
| 1117 | np = ⊤ |
| 1118 | top = NULL; |
| 1119 | while (len > 0) { |
| 1120 | if (m == NULL) { |
| 1121 | KASSERT(len == M_COPYALL, |
| 1122 | ("m_copym, length > size of mbuf chain")); |
| 1123 | break; |
| 1124 | } |
| 1125 | /* |
| 1126 | * Because we are sharing any cluster attachment below, |
| 1127 | * be sure to get an mbuf that does not have a cluster |
| 1128 | * associated with it. |
| 1129 | */ |
| 1130 | if (copyhdr) |
| 1131 | n = m_gethdr(wait, m->m_type); |
| 1132 | else |
| 1133 | n = m_get(wait, m->m_type); |
| 1134 | *np = n; |
| 1135 | if (n == NULL) |
| 1136 | goto nospace; |
| 1137 | if (copyhdr) { |
| 1138 | if (!m_dup_pkthdr(n, m, wait)) |
| 1139 | goto nospace; |
| 1140 | if (len == M_COPYALL) |
| 1141 | n->m_pkthdr.len -= off0; |
| 1142 | else |
| 1143 | n->m_pkthdr.len = len; |
| 1144 | copyhdr = 0; |
| 1145 | } |
| 1146 | n->m_len = min(len, m->m_len - off); |
| 1147 | if (m->m_flags & M_EXT) { |
| 1148 | KKASSERT((n->m_flags & M_EXT) == 0); |
| 1149 | n->m_data = m->m_data + off; |
| 1150 | m->m_ext.ext_ref(m->m_ext.ext_arg); |
| 1151 | n->m_ext = m->m_ext; |
| 1152 | n->m_flags |= m->m_flags & (M_EXT | M_EXT_CLUSTER); |
| 1153 | } else { |
| 1154 | bcopy(mtod(m, caddr_t)+off, mtod(n, caddr_t), |
| 1155 | (unsigned)n->m_len); |
| 1156 | } |
| 1157 | if (len != M_COPYALL) |
| 1158 | len -= n->m_len; |
| 1159 | off = 0; |
| 1160 | m = m->m_next; |
| 1161 | np = &n->m_next; |
| 1162 | } |
| 1163 | if (top == NULL) |
| 1164 | atomic_add_long_nonlocked(&mbstat[mycpu->gd_cpuid].m_mcfail, 1); |
| 1165 | return (top); |
| 1166 | nospace: |
| 1167 | m_freem(top); |
| 1168 | atomic_add_long_nonlocked(&mbstat[mycpu->gd_cpuid].m_mcfail, 1); |
| 1169 | return (NULL); |
| 1170 | } |
| 1171 | |
| 1172 | /* |
| 1173 | * Copy an entire packet, including header (which must be present). |
| 1174 | * An optimization of the common case `m_copym(m, 0, M_COPYALL, how)'. |
| 1175 | * Note that the copy is read-only, because clusters are not copied, |
| 1176 | * only their reference counts are incremented. |
| 1177 | * Preserve alignment of the first mbuf so if the creator has left |
| 1178 | * some room at the beginning (e.g. for inserting protocol headers) |
| 1179 | * the copies also have the room available. |
| 1180 | */ |
| 1181 | struct mbuf * |
| 1182 | m_copypacket(struct mbuf *m, int how) |
| 1183 | { |
| 1184 | struct mbuf *top, *n, *o; |
| 1185 | |
| 1186 | n = m_gethdr(how, m->m_type); |
| 1187 | top = n; |
| 1188 | if (!n) |
| 1189 | goto nospace; |
| 1190 | |
| 1191 | if (!m_dup_pkthdr(n, m, how)) |
| 1192 | goto nospace; |
| 1193 | n->m_len = m->m_len; |
| 1194 | if (m->m_flags & M_EXT) { |
| 1195 | KKASSERT((n->m_flags & M_EXT) == 0); |
| 1196 | n->m_data = m->m_data; |
| 1197 | m->m_ext.ext_ref(m->m_ext.ext_arg); |
| 1198 | n->m_ext = m->m_ext; |
| 1199 | n->m_flags |= m->m_flags & (M_EXT | M_EXT_CLUSTER); |
| 1200 | } else { |
| 1201 | n->m_data = n->m_pktdat + (m->m_data - m->m_pktdat ); |
| 1202 | bcopy(mtod(m, char *), mtod(n, char *), n->m_len); |
| 1203 | } |
| 1204 | |
| 1205 | m = m->m_next; |
| 1206 | while (m) { |
| 1207 | o = m_get(how, m->m_type); |
| 1208 | if (!o) |
| 1209 | goto nospace; |
| 1210 | |
| 1211 | n->m_next = o; |
| 1212 | n = n->m_next; |
| 1213 | |
| 1214 | n->m_len = m->m_len; |
| 1215 | if (m->m_flags & M_EXT) { |
| 1216 | KKASSERT((n->m_flags & M_EXT) == 0); |
| 1217 | n->m_data = m->m_data; |
| 1218 | m->m_ext.ext_ref(m->m_ext.ext_arg); |
| 1219 | n->m_ext = m->m_ext; |
| 1220 | n->m_flags |= m->m_flags & (M_EXT | M_EXT_CLUSTER); |
| 1221 | } else { |
| 1222 | bcopy(mtod(m, char *), mtod(n, char *), n->m_len); |
| 1223 | } |
| 1224 | |
| 1225 | m = m->m_next; |
| 1226 | } |
| 1227 | return top; |
| 1228 | nospace: |
| 1229 | m_freem(top); |
| 1230 | atomic_add_long_nonlocked(&mbstat[mycpu->gd_cpuid].m_mcfail, 1); |
| 1231 | return (NULL); |
| 1232 | } |
| 1233 | |
| 1234 | /* |
| 1235 | * Copy data from an mbuf chain starting "off" bytes from the beginning, |
| 1236 | * continuing for "len" bytes, into the indicated buffer. |
| 1237 | */ |
| 1238 | void |
| 1239 | m_copydata(const struct mbuf *m, int off, int len, caddr_t cp) |
| 1240 | { |
| 1241 | unsigned count; |
| 1242 | |
| 1243 | KASSERT(off >= 0, ("m_copydata, negative off %d", off)); |
| 1244 | KASSERT(len >= 0, ("m_copydata, negative len %d", len)); |
| 1245 | while (off > 0) { |
| 1246 | KASSERT(m != NULL, ("m_copydata, offset > size of mbuf chain")); |
| 1247 | if (off < m->m_len) |
| 1248 | break; |
| 1249 | off -= m->m_len; |
| 1250 | m = m->m_next; |
| 1251 | } |
| 1252 | while (len > 0) { |
| 1253 | KASSERT(m != NULL, ("m_copydata, length > size of mbuf chain")); |
| 1254 | count = min(m->m_len - off, len); |
| 1255 | bcopy(mtod(m, caddr_t) + off, cp, count); |
| 1256 | len -= count; |
| 1257 | cp += count; |
| 1258 | off = 0; |
| 1259 | m = m->m_next; |
| 1260 | } |
| 1261 | } |
| 1262 | |
| 1263 | /* |
| 1264 | * Copy a packet header mbuf chain into a completely new chain, including |
| 1265 | * copying any mbuf clusters. Use this instead of m_copypacket() when |
| 1266 | * you need a writable copy of an mbuf chain. |
| 1267 | */ |
| 1268 | struct mbuf * |
| 1269 | m_dup(struct mbuf *m, int how) |
| 1270 | { |
| 1271 | struct mbuf **p, *top = NULL; |
| 1272 | int remain, moff, nsize; |
| 1273 | |
| 1274 | /* Sanity check */ |
| 1275 | if (m == NULL) |
| 1276 | return (NULL); |
| 1277 | KASSERT((m->m_flags & M_PKTHDR) != 0, ("%s: !PKTHDR", __func__)); |
| 1278 | |
| 1279 | /* While there's more data, get a new mbuf, tack it on, and fill it */ |
| 1280 | remain = m->m_pkthdr.len; |
| 1281 | moff = 0; |
| 1282 | p = ⊤ |
| 1283 | while (remain > 0 || top == NULL) { /* allow m->m_pkthdr.len == 0 */ |
| 1284 | struct mbuf *n; |
| 1285 | |
| 1286 | /* Get the next new mbuf */ |
| 1287 | n = m_getl(remain, how, m->m_type, top == NULL ? M_PKTHDR : 0, |
| 1288 | &nsize); |
| 1289 | if (n == NULL) |
| 1290 | goto nospace; |
| 1291 | if (top == NULL) |
| 1292 | if (!m_dup_pkthdr(n, m, how)) |
| 1293 | goto nospace0; |
| 1294 | |
| 1295 | /* Link it into the new chain */ |
| 1296 | *p = n; |
| 1297 | p = &n->m_next; |
| 1298 | |
| 1299 | /* Copy data from original mbuf(s) into new mbuf */ |
| 1300 | n->m_len = 0; |
| 1301 | while (n->m_len < nsize && m != NULL) { |
| 1302 | int chunk = min(nsize - n->m_len, m->m_len - moff); |
| 1303 | |
| 1304 | bcopy(m->m_data + moff, n->m_data + n->m_len, chunk); |
| 1305 | moff += chunk; |
| 1306 | n->m_len += chunk; |
| 1307 | remain -= chunk; |
| 1308 | if (moff == m->m_len) { |
| 1309 | m = m->m_next; |
| 1310 | moff = 0; |
| 1311 | } |
| 1312 | } |
| 1313 | |
| 1314 | /* Check correct total mbuf length */ |
| 1315 | KASSERT((remain > 0 && m != NULL) || (remain == 0 && m == NULL), |
| 1316 | ("%s: bogus m_pkthdr.len", __func__)); |
| 1317 | } |
| 1318 | return (top); |
| 1319 | |
| 1320 | nospace: |
| 1321 | m_freem(top); |
| 1322 | nospace0: |
| 1323 | atomic_add_long_nonlocked(&mbstat[mycpu->gd_cpuid].m_mcfail, 1); |
| 1324 | return (NULL); |
| 1325 | } |
| 1326 | |
| 1327 | /* |
| 1328 | * Copy the non-packet mbuf data chain into a new set of mbufs, including |
| 1329 | * copying any mbuf clusters. This is typically used to realign a data |
| 1330 | * chain by nfs_realign(). |
| 1331 | * |
| 1332 | * The original chain is left intact. how should be MB_WAIT or MB_DONTWAIT |
| 1333 | * and NULL can be returned if MB_DONTWAIT is passed. |
| 1334 | * |
| 1335 | * Be careful to use cluster mbufs, a large mbuf chain converted to non |
| 1336 | * cluster mbufs can exhaust our supply of mbufs. |
| 1337 | */ |
| 1338 | struct mbuf * |
| 1339 | m_dup_data(struct mbuf *m, int how) |
| 1340 | { |
| 1341 | struct mbuf **p, *n, *top = NULL; |
| 1342 | int mlen, moff, chunk, gsize, nsize; |
| 1343 | |
| 1344 | /* |
| 1345 | * Degenerate case |
| 1346 | */ |
| 1347 | if (m == NULL) |
| 1348 | return (NULL); |
| 1349 | |
| 1350 | /* |
| 1351 | * Optimize the mbuf allocation but do not get too carried away. |
| 1352 | */ |
| 1353 | if (m->m_next || m->m_len > MLEN) |
| 1354 | gsize = MCLBYTES; |
| 1355 | else |
| 1356 | gsize = MLEN; |
| 1357 | |
| 1358 | /* Chain control */ |
| 1359 | p = ⊤ |
| 1360 | n = NULL; |
| 1361 | nsize = 0; |
| 1362 | |
| 1363 | /* |
| 1364 | * Scan the mbuf chain until nothing is left, the new mbuf chain |
| 1365 | * will be allocated on the fly as needed. |
| 1366 | */ |
| 1367 | while (m) { |
| 1368 | mlen = m->m_len; |
| 1369 | moff = 0; |
| 1370 | |
| 1371 | while (mlen) { |
| 1372 | KKASSERT(m->m_type == MT_DATA); |
| 1373 | if (n == NULL) { |
| 1374 | n = m_getl(gsize, how, MT_DATA, 0, &nsize); |
| 1375 | n->m_len = 0; |
| 1376 | if (n == NULL) |
| 1377 | goto nospace; |
| 1378 | *p = n; |
| 1379 | p = &n->m_next; |
| 1380 | } |
| 1381 | chunk = imin(mlen, nsize); |
| 1382 | bcopy(m->m_data + moff, n->m_data + n->m_len, chunk); |
| 1383 | mlen -= chunk; |
| 1384 | moff += chunk; |
| 1385 | n->m_len += chunk; |
| 1386 | nsize -= chunk; |
| 1387 | if (nsize == 0) |
| 1388 | n = NULL; |
| 1389 | } |
| 1390 | m = m->m_next; |
| 1391 | } |
| 1392 | *p = NULL; |
| 1393 | return(top); |
| 1394 | nospace: |
| 1395 | *p = NULL; |
| 1396 | m_freem(top); |
| 1397 | atomic_add_long_nonlocked(&mbstat[mycpu->gd_cpuid].m_mcfail, 1); |
| 1398 | return (NULL); |
| 1399 | } |
| 1400 | |
| 1401 | /* |
| 1402 | * Concatenate mbuf chain n to m. |
| 1403 | * Both chains must be of the same type (e.g. MT_DATA). |
| 1404 | * Any m_pkthdr is not updated. |
| 1405 | */ |
| 1406 | void |
| 1407 | m_cat(struct mbuf *m, struct mbuf *n) |
| 1408 | { |
| 1409 | m = m_last(m); |
| 1410 | while (n) { |
| 1411 | if (m->m_flags & M_EXT || |
| 1412 | m->m_data + m->m_len + n->m_len >= &m->m_dat[MLEN]) { |
| 1413 | /* just join the two chains */ |
| 1414 | m->m_next = n; |
| 1415 | return; |
| 1416 | } |
| 1417 | /* splat the data from one into the other */ |
| 1418 | bcopy(mtod(n, caddr_t), mtod(m, caddr_t) + m->m_len, |
| 1419 | (u_int)n->m_len); |
| 1420 | m->m_len += n->m_len; |
| 1421 | n = m_free(n); |
| 1422 | } |
| 1423 | } |
| 1424 | |
| 1425 | void |
| 1426 | m_adj(struct mbuf *mp, int req_len) |
| 1427 | { |
| 1428 | int len = req_len; |
| 1429 | struct mbuf *m; |
| 1430 | int count; |
| 1431 | |
| 1432 | if ((m = mp) == NULL) |
| 1433 | return; |
| 1434 | if (len >= 0) { |
| 1435 | /* |
| 1436 | * Trim from head. |
| 1437 | */ |
| 1438 | while (m != NULL && len > 0) { |
| 1439 | if (m->m_len <= len) { |
| 1440 | len -= m->m_len; |
| 1441 | m->m_len = 0; |
| 1442 | m = m->m_next; |
| 1443 | } else { |
| 1444 | m->m_len -= len; |
| 1445 | m->m_data += len; |
| 1446 | len = 0; |
| 1447 | } |
| 1448 | } |
| 1449 | m = mp; |
| 1450 | if (mp->m_flags & M_PKTHDR) |
| 1451 | m->m_pkthdr.len -= (req_len - len); |
| 1452 | } else { |
| 1453 | /* |
| 1454 | * Trim from tail. Scan the mbuf chain, |
| 1455 | * calculating its length and finding the last mbuf. |
| 1456 | * If the adjustment only affects this mbuf, then just |
| 1457 | * adjust and return. Otherwise, rescan and truncate |
| 1458 | * after the remaining size. |
| 1459 | */ |
| 1460 | len = -len; |
| 1461 | count = 0; |
| 1462 | for (;;) { |
| 1463 | count += m->m_len; |
| 1464 | if (m->m_next == NULL) |
| 1465 | break; |
| 1466 | m = m->m_next; |
| 1467 | } |
| 1468 | if (m->m_len >= len) { |
| 1469 | m->m_len -= len; |
| 1470 | if (mp->m_flags & M_PKTHDR) |
| 1471 | mp->m_pkthdr.len -= len; |
| 1472 | return; |
| 1473 | } |
| 1474 | count -= len; |
| 1475 | if (count < 0) |
| 1476 | count = 0; |
| 1477 | /* |
| 1478 | * Correct length for chain is "count". |
| 1479 | * Find the mbuf with last data, adjust its length, |
| 1480 | * and toss data from remaining mbufs on chain. |
| 1481 | */ |
| 1482 | m = mp; |
| 1483 | if (m->m_flags & M_PKTHDR) |
| 1484 | m->m_pkthdr.len = count; |
| 1485 | for (; m; m = m->m_next) { |
| 1486 | if (m->m_len >= count) { |
| 1487 | m->m_len = count; |
| 1488 | break; |
| 1489 | } |
| 1490 | count -= m->m_len; |
| 1491 | } |
| 1492 | while (m->m_next) |
| 1493 | (m = m->m_next) ->m_len = 0; |
| 1494 | } |
| 1495 | } |
| 1496 | |
| 1497 | /* |
| 1498 | * Set the m_data pointer of a newly-allocated mbuf |
| 1499 | * to place an object of the specified size at the |
| 1500 | * end of the mbuf, longword aligned. |
| 1501 | */ |
| 1502 | void |
| 1503 | m_align(struct mbuf *m, int len) |
| 1504 | { |
| 1505 | int adjust; |
| 1506 | |
| 1507 | if (m->m_flags & M_EXT) |
| 1508 | adjust = m->m_ext.ext_size - len; |
| 1509 | else if (m->m_flags & M_PKTHDR) |
| 1510 | adjust = MHLEN - len; |
| 1511 | else |
| 1512 | adjust = MLEN - len; |
| 1513 | m->m_data += adjust &~ (sizeof(long)-1); |
| 1514 | } |
| 1515 | |
| 1516 | /* |
| 1517 | * Rearrange an mbuf chain so that len bytes are contiguous |
| 1518 | * and in the data area of an mbuf (so that mtod will work for a structure |
| 1519 | * of size len). Returns the resulting mbuf chain on success, frees it and |
| 1520 | * returns null on failure. If there is room, it will add up to |
| 1521 | * max_protohdr-len extra bytes to the contiguous region in an attempt to |
| 1522 | * avoid being called next time. |
| 1523 | */ |
| 1524 | struct mbuf * |
| 1525 | m_pullup(struct mbuf *n, int len) |
| 1526 | { |
| 1527 | struct mbuf *m; |
| 1528 | int count; |
| 1529 | int space; |
| 1530 | |
| 1531 | /* |
| 1532 | * If first mbuf has no cluster, and has room for len bytes |
| 1533 | * without shifting current data, pullup into it, |
| 1534 | * otherwise allocate a new mbuf to prepend to the chain. |
| 1535 | */ |
| 1536 | if (!(n->m_flags & M_EXT) && |
| 1537 | n->m_data + len < &n->m_dat[MLEN] && |
| 1538 | n->m_next) { |
| 1539 | if (n->m_len >= len) |
| 1540 | return (n); |
| 1541 | m = n; |
| 1542 | n = n->m_next; |
| 1543 | len -= m->m_len; |
| 1544 | } else { |
| 1545 | if (len > MHLEN) |
| 1546 | goto bad; |
| 1547 | if (n->m_flags & M_PKTHDR) |
| 1548 | m = m_gethdr(MB_DONTWAIT, n->m_type); |
| 1549 | else |
| 1550 | m = m_get(MB_DONTWAIT, n->m_type); |
| 1551 | if (m == NULL) |
| 1552 | goto bad; |
| 1553 | m->m_len = 0; |
| 1554 | if (n->m_flags & M_PKTHDR) |
| 1555 | M_MOVE_PKTHDR(m, n); |
| 1556 | } |
| 1557 | space = &m->m_dat[MLEN] - (m->m_data + m->m_len); |
| 1558 | do { |
| 1559 | count = min(min(max(len, max_protohdr), space), n->m_len); |
| 1560 | bcopy(mtod(n, caddr_t), mtod(m, caddr_t) + m->m_len, |
| 1561 | (unsigned)count); |
| 1562 | len -= count; |
| 1563 | m->m_len += count; |
| 1564 | n->m_len -= count; |
| 1565 | space -= count; |
| 1566 | if (n->m_len) |
| 1567 | n->m_data += count; |
| 1568 | else |
| 1569 | n = m_free(n); |
| 1570 | } while (len > 0 && n); |
| 1571 | if (len > 0) { |
| 1572 | m_free(m); |
| 1573 | goto bad; |
| 1574 | } |
| 1575 | m->m_next = n; |
| 1576 | return (m); |
| 1577 | bad: |
| 1578 | m_freem(n); |
| 1579 | atomic_add_long_nonlocked(&mbstat[mycpu->gd_cpuid].m_mcfail, 1); |
| 1580 | return (NULL); |
| 1581 | } |
| 1582 | |
| 1583 | /* |
| 1584 | * Partition an mbuf chain in two pieces, returning the tail -- |
| 1585 | * all but the first len0 bytes. In case of failure, it returns NULL and |
| 1586 | * attempts to restore the chain to its original state. |
| 1587 | * |
| 1588 | * Note that the resulting mbufs might be read-only, because the new |
| 1589 | * mbuf can end up sharing an mbuf cluster with the original mbuf if |
| 1590 | * the "breaking point" happens to lie within a cluster mbuf. Use the |
| 1591 | * M_WRITABLE() macro to check for this case. |
| 1592 | */ |
| 1593 | struct mbuf * |
| 1594 | m_split(struct mbuf *m0, int len0, int wait) |
| 1595 | { |
| 1596 | struct mbuf *m, *n; |
| 1597 | unsigned len = len0, remain; |
| 1598 | |
| 1599 | for (m = m0; m && len > m->m_len; m = m->m_next) |
| 1600 | len -= m->m_len; |
| 1601 | if (m == NULL) |
| 1602 | return (NULL); |
| 1603 | remain = m->m_len - len; |
| 1604 | if (m0->m_flags & M_PKTHDR) { |
| 1605 | n = m_gethdr(wait, m0->m_type); |
| 1606 | if (n == NULL) |
| 1607 | return (NULL); |
| 1608 | n->m_pkthdr.rcvif = m0->m_pkthdr.rcvif; |
| 1609 | n->m_pkthdr.len = m0->m_pkthdr.len - len0; |
| 1610 | m0->m_pkthdr.len = len0; |
| 1611 | if (m->m_flags & M_EXT) |
| 1612 | goto extpacket; |
| 1613 | if (remain > MHLEN) { |
| 1614 | /* m can't be the lead packet */ |
| 1615 | MH_ALIGN(n, 0); |
| 1616 | n->m_next = m_split(m, len, wait); |
| 1617 | if (n->m_next == NULL) { |
| 1618 | m_free(n); |
| 1619 | return (NULL); |
| 1620 | } else { |
| 1621 | n->m_len = 0; |
| 1622 | return (n); |
| 1623 | } |
| 1624 | } else |
| 1625 | MH_ALIGN(n, remain); |
| 1626 | } else if (remain == 0) { |
| 1627 | n = m->m_next; |
| 1628 | m->m_next = 0; |
| 1629 | return (n); |
| 1630 | } else { |
| 1631 | n = m_get(wait, m->m_type); |
| 1632 | if (n == NULL) |
| 1633 | return (NULL); |
| 1634 | M_ALIGN(n, remain); |
| 1635 | } |
| 1636 | extpacket: |
| 1637 | if (m->m_flags & M_EXT) { |
| 1638 | KKASSERT((n->m_flags & M_EXT) == 0); |
| 1639 | n->m_data = m->m_data + len; |
| 1640 | m->m_ext.ext_ref(m->m_ext.ext_arg); |
| 1641 | n->m_ext = m->m_ext; |
| 1642 | n->m_flags |= m->m_flags & (M_EXT | M_EXT_CLUSTER); |
| 1643 | } else { |
| 1644 | bcopy(mtod(m, caddr_t) + len, mtod(n, caddr_t), remain); |
| 1645 | } |
| 1646 | n->m_len = remain; |
| 1647 | m->m_len = len; |
| 1648 | n->m_next = m->m_next; |
| 1649 | m->m_next = 0; |
| 1650 | return (n); |
| 1651 | } |
| 1652 | |
| 1653 | /* |
| 1654 | * Routine to copy from device local memory into mbufs. |
| 1655 | * Note: "offset" is ill-defined and always called as 0, so ignore it. |
| 1656 | */ |
| 1657 | struct mbuf * |
| 1658 | m_devget(char *buf, int len, int offset, struct ifnet *ifp, |
| 1659 | void (*copy)(volatile const void *from, volatile void *to, size_t length)) |
| 1660 | { |
| 1661 | struct mbuf *m, *mfirst = NULL, **mtail; |
| 1662 | int nsize, flags; |
| 1663 | |
| 1664 | if (copy == NULL) |
| 1665 | copy = bcopy; |
| 1666 | mtail = &mfirst; |
| 1667 | flags = M_PKTHDR; |
| 1668 | |
| 1669 | while (len > 0) { |
| 1670 | m = m_getl(len, MB_DONTWAIT, MT_DATA, flags, &nsize); |
| 1671 | if (m == NULL) { |
| 1672 | m_freem(mfirst); |
| 1673 | return (NULL); |
| 1674 | } |
| 1675 | m->m_len = min(len, nsize); |
| 1676 | |
| 1677 | if (flags & M_PKTHDR) { |
| 1678 | if (len + max_linkhdr <= nsize) |
| 1679 | m->m_data += max_linkhdr; |
| 1680 | m->m_pkthdr.rcvif = ifp; |
| 1681 | m->m_pkthdr.len = len; |
| 1682 | flags = 0; |
| 1683 | } |
| 1684 | |
| 1685 | copy(buf, m->m_data, (unsigned)m->m_len); |
| 1686 | buf += m->m_len; |
| 1687 | len -= m->m_len; |
| 1688 | *mtail = m; |
| 1689 | mtail = &m->m_next; |
| 1690 | } |
| 1691 | |
| 1692 | return (mfirst); |
| 1693 | } |
| 1694 | |
| 1695 | /* |
| 1696 | * Routine to pad mbuf to the specified length 'padto'. |
| 1697 | */ |
| 1698 | int |
| 1699 | m_devpad(struct mbuf *m, int padto) |
| 1700 | { |
| 1701 | struct mbuf *last = NULL; |
| 1702 | int padlen; |
| 1703 | |
| 1704 | if (padto <= m->m_pkthdr.len) |
| 1705 | return 0; |
| 1706 | |
| 1707 | padlen = padto - m->m_pkthdr.len; |
| 1708 | |
| 1709 | /* if there's only the packet-header and we can pad there, use it. */ |
| 1710 | if (m->m_pkthdr.len == m->m_len && M_TRAILINGSPACE(m) >= padlen) { |
| 1711 | last = m; |
| 1712 | } else { |
| 1713 | /* |
| 1714 | * Walk packet chain to find last mbuf. We will either |
| 1715 | * pad there, or append a new mbuf and pad it |
| 1716 | */ |
| 1717 | for (last = m; last->m_next != NULL; last = last->m_next) |
| 1718 | ; /* EMPTY */ |
| 1719 | |
| 1720 | /* `last' now points to last in chain. */ |
| 1721 | if (M_TRAILINGSPACE(last) < padlen) { |
| 1722 | struct mbuf *n; |
| 1723 | |
| 1724 | /* Allocate new empty mbuf, pad it. Compact later. */ |
| 1725 | MGET(n, MB_DONTWAIT, MT_DATA); |
| 1726 | if (n == NULL) |
| 1727 | return ENOBUFS; |
| 1728 | n->m_len = 0; |
| 1729 | last->m_next = n; |
| 1730 | last = n; |
| 1731 | } |
| 1732 | } |
| 1733 | KKASSERT(M_TRAILINGSPACE(last) >= padlen); |
| 1734 | KKASSERT(M_WRITABLE(last)); |
| 1735 | |
| 1736 | /* Now zero the pad area */ |
| 1737 | bzero(mtod(last, char *) + last->m_len, padlen); |
| 1738 | last->m_len += padlen; |
| 1739 | m->m_pkthdr.len += padlen; |
| 1740 | return 0; |
| 1741 | } |
| 1742 | |
| 1743 | /* |
| 1744 | * Copy data from a buffer back into the indicated mbuf chain, |
| 1745 | * starting "off" bytes from the beginning, extending the mbuf |
| 1746 | * chain if necessary. |
| 1747 | */ |
| 1748 | void |
| 1749 | m_copyback(struct mbuf *m0, int off, int len, caddr_t cp) |
| 1750 | { |
| 1751 | int mlen; |
| 1752 | struct mbuf *m = m0, *n; |
| 1753 | int totlen = 0; |
| 1754 | |
| 1755 | if (m0 == NULL) |
| 1756 | return; |
| 1757 | while (off > (mlen = m->m_len)) { |
| 1758 | off -= mlen; |
| 1759 | totlen += mlen; |
| 1760 | if (m->m_next == NULL) { |
| 1761 | n = m_getclr(MB_DONTWAIT, m->m_type); |
| 1762 | if (n == NULL) |
| 1763 | goto out; |
| 1764 | n->m_len = min(MLEN, len + off); |
| 1765 | m->m_next = n; |
| 1766 | } |
| 1767 | m = m->m_next; |
| 1768 | } |
| 1769 | while (len > 0) { |
| 1770 | mlen = min (m->m_len - off, len); |
| 1771 | bcopy(cp, off + mtod(m, caddr_t), (unsigned)mlen); |
| 1772 | cp += mlen; |
| 1773 | len -= mlen; |
| 1774 | mlen += off; |
| 1775 | off = 0; |
| 1776 | totlen += mlen; |
| 1777 | if (len == 0) |
| 1778 | break; |
| 1779 | if (m->m_next == NULL) { |
| 1780 | n = m_get(MB_DONTWAIT, m->m_type); |
| 1781 | if (n == NULL) |
| 1782 | break; |
| 1783 | n->m_len = min(MLEN, len); |
| 1784 | m->m_next = n; |
| 1785 | } |
| 1786 | m = m->m_next; |
| 1787 | } |
| 1788 | out: if (((m = m0)->m_flags & M_PKTHDR) && (m->m_pkthdr.len < totlen)) |
| 1789 | m->m_pkthdr.len = totlen; |
| 1790 | } |
| 1791 | |
| 1792 | /* |
| 1793 | * Append the specified data to the indicated mbuf chain, |
| 1794 | * Extend the mbuf chain if the new data does not fit in |
| 1795 | * existing space. |
| 1796 | * |
| 1797 | * Return 1 if able to complete the job; otherwise 0. |
| 1798 | */ |
| 1799 | int |
| 1800 | m_append(struct mbuf *m0, int len, c_caddr_t cp) |
| 1801 | { |
| 1802 | struct mbuf *m, *n; |
| 1803 | int remainder, space; |
| 1804 | |
| 1805 | for (m = m0; m->m_next != NULL; m = m->m_next) |
| 1806 | ; |
| 1807 | remainder = len; |
| 1808 | space = M_TRAILINGSPACE(m); |
| 1809 | if (space > 0) { |
| 1810 | /* |
| 1811 | * Copy into available space. |
| 1812 | */ |
| 1813 | if (space > remainder) |
| 1814 | space = remainder; |
| 1815 | bcopy(cp, mtod(m, caddr_t) + m->m_len, space); |
| 1816 | m->m_len += space; |
| 1817 | cp += space, remainder -= space; |
| 1818 | } |
| 1819 | while (remainder > 0) { |
| 1820 | /* |
| 1821 | * Allocate a new mbuf; could check space |
| 1822 | * and allocate a cluster instead. |
| 1823 | */ |
| 1824 | n = m_get(MB_DONTWAIT, m->m_type); |
| 1825 | if (n == NULL) |
| 1826 | break; |
| 1827 | n->m_len = min(MLEN, remainder); |
| 1828 | bcopy(cp, mtod(n, caddr_t), n->m_len); |
| 1829 | cp += n->m_len, remainder -= n->m_len; |
| 1830 | m->m_next = n; |
| 1831 | m = n; |
| 1832 | } |
| 1833 | if (m0->m_flags & M_PKTHDR) |
| 1834 | m0->m_pkthdr.len += len - remainder; |
| 1835 | return (remainder == 0); |
| 1836 | } |
| 1837 | |
| 1838 | /* |
| 1839 | * Apply function f to the data in an mbuf chain starting "off" bytes from |
| 1840 | * the beginning, continuing for "len" bytes. |
| 1841 | */ |
| 1842 | int |
| 1843 | m_apply(struct mbuf *m, int off, int len, |
| 1844 | int (*f)(void *, void *, u_int), void *arg) |
| 1845 | { |
| 1846 | u_int count; |
| 1847 | int rval; |
| 1848 | |
| 1849 | KASSERT(off >= 0, ("m_apply, negative off %d", off)); |
| 1850 | KASSERT(len >= 0, ("m_apply, negative len %d", len)); |
| 1851 | while (off > 0) { |
| 1852 | KASSERT(m != NULL, ("m_apply, offset > size of mbuf chain")); |
| 1853 | if (off < m->m_len) |
| 1854 | break; |
| 1855 | off -= m->m_len; |
| 1856 | m = m->m_next; |
| 1857 | } |
| 1858 | while (len > 0) { |
| 1859 | KASSERT(m != NULL, ("m_apply, offset > size of mbuf chain")); |
| 1860 | count = min(m->m_len - off, len); |
| 1861 | rval = (*f)(arg, mtod(m, caddr_t) + off, count); |
| 1862 | if (rval) |
| 1863 | return (rval); |
| 1864 | len -= count; |
| 1865 | off = 0; |
| 1866 | m = m->m_next; |
| 1867 | } |
| 1868 | return (0); |
| 1869 | } |
| 1870 | |
| 1871 | /* |
| 1872 | * Return a pointer to mbuf/offset of location in mbuf chain. |
| 1873 | */ |
| 1874 | struct mbuf * |
| 1875 | m_getptr(struct mbuf *m, int loc, int *off) |
| 1876 | { |
| 1877 | |
| 1878 | while (loc >= 0) { |
| 1879 | /* Normal end of search. */ |
| 1880 | if (m->m_len > loc) { |
| 1881 | *off = loc; |
| 1882 | return (m); |
| 1883 | } else { |
| 1884 | loc -= m->m_len; |
| 1885 | if (m->m_next == NULL) { |
| 1886 | if (loc == 0) { |
| 1887 | /* Point at the end of valid data. */ |
| 1888 | *off = m->m_len; |
| 1889 | return (m); |
| 1890 | } |
| 1891 | return (NULL); |
| 1892 | } |
| 1893 | m = m->m_next; |
| 1894 | } |
| 1895 | } |
| 1896 | return (NULL); |
| 1897 | } |
| 1898 | |
| 1899 | void |
| 1900 | m_print(const struct mbuf *m) |
| 1901 | { |
| 1902 | int len; |
| 1903 | const struct mbuf *m2; |
| 1904 | |
| 1905 | len = m->m_pkthdr.len; |
| 1906 | m2 = m; |
| 1907 | while (len) { |
| 1908 | kprintf("%p %*D\n", m2, m2->m_len, (u_char *)m2->m_data, "-"); |
| 1909 | len -= m2->m_len; |
| 1910 | m2 = m2->m_next; |
| 1911 | } |
| 1912 | return; |
| 1913 | } |
| 1914 | |
| 1915 | /* |
| 1916 | * "Move" mbuf pkthdr from "from" to "to". |
| 1917 | * "from" must have M_PKTHDR set, and "to" must be empty. |
| 1918 | */ |
| 1919 | void |
| 1920 | m_move_pkthdr(struct mbuf *to, struct mbuf *from) |
| 1921 | { |
| 1922 | KASSERT((to->m_flags & M_PKTHDR), ("m_move_pkthdr: not packet header")); |
| 1923 | |
| 1924 | to->m_flags |= from->m_flags & M_COPYFLAGS; |
| 1925 | to->m_pkthdr = from->m_pkthdr; /* especially tags */ |
| 1926 | SLIST_INIT(&from->m_pkthdr.tags); /* purge tags from src */ |
| 1927 | } |
| 1928 | |
| 1929 | /* |
| 1930 | * Duplicate "from"'s mbuf pkthdr in "to". |
| 1931 | * "from" must have M_PKTHDR set, and "to" must be empty. |
| 1932 | * In particular, this does a deep copy of the packet tags. |
| 1933 | */ |
| 1934 | int |
| 1935 | m_dup_pkthdr(struct mbuf *to, const struct mbuf *from, int how) |
| 1936 | { |
| 1937 | KASSERT((to->m_flags & M_PKTHDR), ("m_dup_pkthdr: not packet header")); |
| 1938 | |
| 1939 | to->m_flags = (from->m_flags & M_COPYFLAGS) | |
| 1940 | (to->m_flags & ~M_COPYFLAGS); |
| 1941 | to->m_pkthdr = from->m_pkthdr; |
| 1942 | SLIST_INIT(&to->m_pkthdr.tags); |
| 1943 | return (m_tag_copy_chain(to, from, how)); |
| 1944 | } |
| 1945 | |
| 1946 | /* |
| 1947 | * Defragment a mbuf chain, returning the shortest possible |
| 1948 | * chain of mbufs and clusters. If allocation fails and |
| 1949 | * this cannot be completed, NULL will be returned, but |
| 1950 | * the passed in chain will be unchanged. Upon success, |
| 1951 | * the original chain will be freed, and the new chain |
| 1952 | * will be returned. |
| 1953 | * |
| 1954 | * If a non-packet header is passed in, the original |
| 1955 | * mbuf (chain?) will be returned unharmed. |
| 1956 | * |
| 1957 | * m_defrag_nofree doesn't free the passed in mbuf. |
| 1958 | */ |
| 1959 | struct mbuf * |
| 1960 | m_defrag(struct mbuf *m0, int how) |
| 1961 | { |
| 1962 | struct mbuf *m_new; |
| 1963 | |
| 1964 | if ((m_new = m_defrag_nofree(m0, how)) == NULL) |
| 1965 | return (NULL); |
| 1966 | if (m_new != m0) |
| 1967 | m_freem(m0); |
| 1968 | return (m_new); |
| 1969 | } |
| 1970 | |
| 1971 | struct mbuf * |
| 1972 | m_defrag_nofree(struct mbuf *m0, int how) |
| 1973 | { |
| 1974 | struct mbuf *m_new = NULL, *m_final = NULL; |
| 1975 | int progress = 0, length, nsize; |
| 1976 | |
| 1977 | if (!(m0->m_flags & M_PKTHDR)) |
| 1978 | return (m0); |
| 1979 | |
| 1980 | #ifdef MBUF_STRESS_TEST |
| 1981 | if (m_defragrandomfailures) { |
| 1982 | int temp = karc4random() & 0xff; |
| 1983 | if (temp == 0xba) |
| 1984 | goto nospace; |
| 1985 | } |
| 1986 | #endif |
| 1987 | |
| 1988 | m_final = m_getl(m0->m_pkthdr.len, how, MT_DATA, M_PKTHDR, &nsize); |
| 1989 | if (m_final == NULL) |
| 1990 | goto nospace; |
| 1991 | m_final->m_len = 0; /* in case m0->m_pkthdr.len is zero */ |
| 1992 | |
| 1993 | if (m_dup_pkthdr(m_final, m0, how) == 0) |
| 1994 | goto nospace; |
| 1995 | |
| 1996 | m_new = m_final; |
| 1997 | |
| 1998 | while (progress < m0->m_pkthdr.len) { |
| 1999 | length = m0->m_pkthdr.len - progress; |
| 2000 | if (length > MCLBYTES) |
| 2001 | length = MCLBYTES; |
| 2002 | |
| 2003 | if (m_new == NULL) { |
| 2004 | m_new = m_getl(length, how, MT_DATA, 0, &nsize); |
| 2005 | if (m_new == NULL) |
| 2006 | goto nospace; |
| 2007 | } |
| 2008 | |
| 2009 | m_copydata(m0, progress, length, mtod(m_new, caddr_t)); |
| 2010 | progress += length; |
| 2011 | m_new->m_len = length; |
| 2012 | if (m_new != m_final) |
| 2013 | m_cat(m_final, m_new); |
| 2014 | m_new = NULL; |
| 2015 | } |
| 2016 | if (m0->m_next == NULL) |
| 2017 | m_defraguseless++; |
| 2018 | m_defragpackets++; |
| 2019 | m_defragbytes += m_final->m_pkthdr.len; |
| 2020 | return (m_final); |
| 2021 | nospace: |
| 2022 | m_defragfailure++; |
| 2023 | if (m_new) |
| 2024 | m_free(m_new); |
| 2025 | m_freem(m_final); |
| 2026 | return (NULL); |
| 2027 | } |
| 2028 | |
| 2029 | /* |
| 2030 | * Move data from uio into mbufs. |
| 2031 | */ |
| 2032 | struct mbuf * |
| 2033 | m_uiomove(struct uio *uio) |
| 2034 | { |
| 2035 | struct mbuf *m; /* current working mbuf */ |
| 2036 | struct mbuf *head = NULL; /* result mbuf chain */ |
| 2037 | struct mbuf **mp = &head; |
| 2038 | int flags = M_PKTHDR; |
| 2039 | int nsize; |
| 2040 | int error; |
| 2041 | int resid; |
| 2042 | |
| 2043 | do { |
| 2044 | if (uio->uio_resid > INT_MAX) |
| 2045 | resid = INT_MAX; |
| 2046 | else |
| 2047 | resid = (int)uio->uio_resid; |
| 2048 | m = m_getl(resid, MB_WAIT, MT_DATA, flags, &nsize); |
| 2049 | if (flags) { |
| 2050 | m->m_pkthdr.len = 0; |
| 2051 | /* Leave room for protocol headers. */ |
| 2052 | if (resid < MHLEN) |
| 2053 | MH_ALIGN(m, resid); |
| 2054 | flags = 0; |
| 2055 | } |
| 2056 | m->m_len = imin(nsize, resid); |
| 2057 | error = uiomove(mtod(m, caddr_t), m->m_len, uio); |
| 2058 | if (error) { |
| 2059 | m_free(m); |
| 2060 | goto failed; |
| 2061 | } |
| 2062 | *mp = m; |
| 2063 | mp = &m->m_next; |
| 2064 | head->m_pkthdr.len += m->m_len; |
| 2065 | } while (uio->uio_resid > 0); |
| 2066 | |
| 2067 | return (head); |
| 2068 | |
| 2069 | failed: |
| 2070 | m_freem(head); |
| 2071 | return (NULL); |
| 2072 | } |
| 2073 | |
| 2074 | struct mbuf * |
| 2075 | m_last(struct mbuf *m) |
| 2076 | { |
| 2077 | while (m->m_next) |
| 2078 | m = m->m_next; |
| 2079 | return (m); |
| 2080 | } |
| 2081 | |
| 2082 | /* |
| 2083 | * Return the number of bytes in an mbuf chain. |
| 2084 | * If lastm is not NULL, also return the last mbuf. |
| 2085 | */ |
| 2086 | u_int |
| 2087 | m_lengthm(struct mbuf *m, struct mbuf **lastm) |
| 2088 | { |
| 2089 | u_int len = 0; |
| 2090 | struct mbuf *prev = m; |
| 2091 | |
| 2092 | while (m) { |
| 2093 | len += m->m_len; |
| 2094 | prev = m; |
| 2095 | m = m->m_next; |
| 2096 | } |
| 2097 | if (lastm != NULL) |
| 2098 | *lastm = prev; |
| 2099 | return (len); |
| 2100 | } |
| 2101 | |
| 2102 | /* |
| 2103 | * Like m_lengthm(), except also keep track of mbuf usage. |
| 2104 | */ |
| 2105 | u_int |
| 2106 | m_countm(struct mbuf *m, struct mbuf **lastm, u_int *pmbcnt) |
| 2107 | { |
| 2108 | u_int len = 0, mbcnt = 0; |
| 2109 | struct mbuf *prev = m; |
| 2110 | |
| 2111 | while (m) { |
| 2112 | len += m->m_len; |
| 2113 | mbcnt += MSIZE; |
| 2114 | if (m->m_flags & M_EXT) |
| 2115 | mbcnt += m->m_ext.ext_size; |
| 2116 | prev = m; |
| 2117 | m = m->m_next; |
| 2118 | } |
| 2119 | if (lastm != NULL) |
| 2120 | *lastm = prev; |
| 2121 | *pmbcnt = mbcnt; |
| 2122 | return (len); |
| 2123 | } |