2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
4 * Copyright (c) 2004, 2005,
5 * Bosko Milekic <bmilekic@FreeBSD.org>. All rights reserved.
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
10 * 1. Redistributions of source code must retain the above copyright
11 * notice unmodified, this list of conditions and the following
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 #include <sys/cdefs.h>
31 __FBSDID("$FreeBSD$");
33 #include "opt_param.h"
34 #include "opt_kern_tls.h"
36 #include <sys/param.h>
38 #include <sys/domainset.h>
39 #include <sys/malloc.h>
40 #include <sys/systm.h>
42 #include <sys/domain.h>
43 #include <sys/eventhandler.h>
44 #include <sys/kernel.h>
46 #include <sys/limits.h>
48 #include <sys/mutex.h>
49 #include <sys/protosw.h>
50 #include <sys/refcount.h>
51 #include <sys/sf_buf.h>
53 #include <sys/socket.h>
54 #include <sys/sysctl.h>
57 #include <net/if_var.h>
60 #include <vm/vm_extern.h>
61 #include <vm/vm_kern.h>
62 #include <vm/vm_page.h>
63 #include <vm/vm_map.h>
65 #include <vm/uma_dbg.h>
68 * In FreeBSD, Mbufs and Mbuf Clusters are allocated from UMA
71 * Mbuf Clusters (2K, contiguous) are allocated from the Cluster
72 * Zone. The Zone can be capped at kern.ipc.nmbclusters, if the
73 * administrator so desires.
75 * Mbufs are allocated from a UMA Master Zone called the Mbuf
78 * Additionally, FreeBSD provides a Packet Zone, which it
79 * configures as a Secondary Zone to the Mbuf Master Zone,
80 * thus sharing backend Slab kegs with the Mbuf Master Zone.
82 * Thus common-case allocations and locking are simplified:
86 * | .------------>[(Packet Cache)] m_get(), m_gethdr()
88 * [(Cluster Cache)] [ Secondary ] [ (Mbuf Cache) ]
89 * [ Cluster Zone ] [ Zone ] [ Mbuf Master Zone ]
95 * \____________(VM)_________________/
98 * Whenever an object is allocated with uma_zalloc() out of
99 * one of the Zones its _ctor_ function is executed. The same
100 * for any deallocation through uma_zfree() the _dtor_ function
103 * Caches are per-CPU and are filled from the Master Zone.
105 * Whenever an object is allocated from the underlying global
106 * memory pool it gets pre-initialized with the _zinit_ functions.
107 * When the Keg's are overfull objects get decommissioned with
108 * _zfini_ functions and free'd back to the global memory pool.
112 int nmbufs; /* limits number of mbufs */
113 int nmbclusters; /* limits number of mbuf clusters */
114 int nmbjumbop; /* limits number of page size jumbo clusters */
115 int nmbjumbo9; /* limits number of 9k jumbo clusters */
116 int nmbjumbo16; /* limits number of 16k jumbo clusters */
118 bool mb_use_ext_pgs; /* use EXT_PGS mbufs for sendfile & TLS */
119 SYSCTL_BOOL(_kern_ipc, OID_AUTO, mb_use_ext_pgs, CTLFLAG_RWTUN,
121 "Use unmapped mbufs for sendfile(2) and TLS offload");
123 static quad_t maxmbufmem; /* overall real memory limit for all mbufs */
125 SYSCTL_QUAD(_kern_ipc, OID_AUTO, maxmbufmem, CTLFLAG_RDTUN | CTLFLAG_NOFETCH, &maxmbufmem, 0,
126 "Maximum real memory allocatable to various mbuf types");
128 static counter_u64_t snd_tag_count;
129 SYSCTL_COUNTER_U64(_kern_ipc, OID_AUTO, num_snd_tags, CTLFLAG_RW,
130 &snd_tag_count, "# of active mbuf send tags");
133 * tunable_mbinit() has to be run before any mbuf allocations are done.
136 tunable_mbinit(void *dummy)
141 * The default limit for all mbuf related memory is 1/2 of all
142 * available kernel memory (physical or kmem).
143 * At most it can be 3/4 of available kernel memory.
145 realmem = qmin((quad_t)physmem * PAGE_SIZE, vm_kmem_size);
146 maxmbufmem = realmem / 2;
147 TUNABLE_QUAD_FETCH("kern.ipc.maxmbufmem", &maxmbufmem);
148 if (maxmbufmem > realmem / 4 * 3)
149 maxmbufmem = realmem / 4 * 3;
151 TUNABLE_INT_FETCH("kern.ipc.nmbclusters", &nmbclusters);
152 if (nmbclusters == 0)
153 nmbclusters = maxmbufmem / MCLBYTES / 4;
155 TUNABLE_INT_FETCH("kern.ipc.nmbjumbop", &nmbjumbop);
157 nmbjumbop = maxmbufmem / MJUMPAGESIZE / 4;
159 TUNABLE_INT_FETCH("kern.ipc.nmbjumbo9", &nmbjumbo9);
161 nmbjumbo9 = maxmbufmem / MJUM9BYTES / 6;
163 TUNABLE_INT_FETCH("kern.ipc.nmbjumbo16", &nmbjumbo16);
165 nmbjumbo16 = maxmbufmem / MJUM16BYTES / 6;
168 * We need at least as many mbufs as we have clusters of
169 * the various types added together.
171 TUNABLE_INT_FETCH("kern.ipc.nmbufs", &nmbufs);
172 if (nmbufs < nmbclusters + nmbjumbop + nmbjumbo9 + nmbjumbo16)
173 nmbufs = lmax(maxmbufmem / MSIZE / 5,
174 nmbclusters + nmbjumbop + nmbjumbo9 + nmbjumbo16);
176 SYSINIT(tunable_mbinit, SI_SUB_KMEM, SI_ORDER_MIDDLE, tunable_mbinit, NULL);
179 sysctl_nmbclusters(SYSCTL_HANDLER_ARGS)
181 int error, newnmbclusters;
183 newnmbclusters = nmbclusters;
184 error = sysctl_handle_int(oidp, &newnmbclusters, 0, req);
185 if (error == 0 && req->newptr && newnmbclusters != nmbclusters) {
186 if (newnmbclusters > nmbclusters &&
187 nmbufs >= nmbclusters + nmbjumbop + nmbjumbo9 + nmbjumbo16) {
188 nmbclusters = newnmbclusters;
189 nmbclusters = uma_zone_set_max(zone_clust, nmbclusters);
190 EVENTHANDLER_INVOKE(nmbclusters_change);
196 SYSCTL_PROC(_kern_ipc, OID_AUTO, nmbclusters,
197 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT, &nmbclusters, 0,
198 sysctl_nmbclusters, "IU",
199 "Maximum number of mbuf clusters allowed");
202 sysctl_nmbjumbop(SYSCTL_HANDLER_ARGS)
204 int error, newnmbjumbop;
206 newnmbjumbop = nmbjumbop;
207 error = sysctl_handle_int(oidp, &newnmbjumbop, 0, req);
208 if (error == 0 && req->newptr && newnmbjumbop != nmbjumbop) {
209 if (newnmbjumbop > nmbjumbop &&
210 nmbufs >= nmbclusters + nmbjumbop + nmbjumbo9 + nmbjumbo16) {
211 nmbjumbop = newnmbjumbop;
212 nmbjumbop = uma_zone_set_max(zone_jumbop, nmbjumbop);
218 SYSCTL_PROC(_kern_ipc, OID_AUTO, nmbjumbop,
219 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT, &nmbjumbop, 0,
220 sysctl_nmbjumbop, "IU",
221 "Maximum number of mbuf page size jumbo clusters allowed");
224 sysctl_nmbjumbo9(SYSCTL_HANDLER_ARGS)
226 int error, newnmbjumbo9;
228 newnmbjumbo9 = nmbjumbo9;
229 error = sysctl_handle_int(oidp, &newnmbjumbo9, 0, req);
230 if (error == 0 && req->newptr && newnmbjumbo9 != nmbjumbo9) {
231 if (newnmbjumbo9 > nmbjumbo9 &&
232 nmbufs >= nmbclusters + nmbjumbop + nmbjumbo9 + nmbjumbo16) {
233 nmbjumbo9 = newnmbjumbo9;
234 nmbjumbo9 = uma_zone_set_max(zone_jumbo9, nmbjumbo9);
240 SYSCTL_PROC(_kern_ipc, OID_AUTO, nmbjumbo9,
241 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT, &nmbjumbo9, 0,
242 sysctl_nmbjumbo9, "IU",
243 "Maximum number of mbuf 9k jumbo clusters allowed");
246 sysctl_nmbjumbo16(SYSCTL_HANDLER_ARGS)
248 int error, newnmbjumbo16;
250 newnmbjumbo16 = nmbjumbo16;
251 error = sysctl_handle_int(oidp, &newnmbjumbo16, 0, req);
252 if (error == 0 && req->newptr && newnmbjumbo16 != nmbjumbo16) {
253 if (newnmbjumbo16 > nmbjumbo16 &&
254 nmbufs >= nmbclusters + nmbjumbop + nmbjumbo9 + nmbjumbo16) {
255 nmbjumbo16 = newnmbjumbo16;
256 nmbjumbo16 = uma_zone_set_max(zone_jumbo16, nmbjumbo16);
262 SYSCTL_PROC(_kern_ipc, OID_AUTO, nmbjumbo16,
263 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT, &nmbjumbo16, 0,
264 sysctl_nmbjumbo16, "IU",
265 "Maximum number of mbuf 16k jumbo clusters allowed");
268 sysctl_nmbufs(SYSCTL_HANDLER_ARGS)
270 int error, newnmbufs;
273 error = sysctl_handle_int(oidp, &newnmbufs, 0, req);
274 if (error == 0 && req->newptr && newnmbufs != nmbufs) {
275 if (newnmbufs > nmbufs) {
277 nmbufs = uma_zone_set_max(zone_mbuf, nmbufs);
278 EVENTHANDLER_INVOKE(nmbufs_change);
284 SYSCTL_PROC(_kern_ipc, OID_AUTO, nmbufs,
285 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT,
286 &nmbufs, 0, sysctl_nmbufs, "IU",
287 "Maximum number of mbufs allowed");
290 * Zones from which we allocate.
292 uma_zone_t zone_mbuf;
293 uma_zone_t zone_clust;
294 uma_zone_t zone_pack;
295 uma_zone_t zone_jumbop;
296 uma_zone_t zone_jumbo9;
297 uma_zone_t zone_jumbo16;
298 uma_zone_t zone_extpgs;
303 static int mb_ctor_mbuf(void *, int, void *, int);
304 static int mb_ctor_clust(void *, int, void *, int);
305 static int mb_ctor_pack(void *, int, void *, int);
306 static void mb_dtor_mbuf(void *, int, void *);
307 static void mb_dtor_pack(void *, int, void *);
308 static int mb_zinit_pack(void *, int, int);
309 static void mb_zfini_pack(void *, int);
310 static void mb_reclaim(uma_zone_t, int);
312 /* Ensure that MSIZE is a power of 2. */
313 CTASSERT((((MSIZE - 1) ^ MSIZE) + 1) >> 1 == MSIZE);
315 _Static_assert(sizeof(struct mbuf_ext_pgs) == 256,
316 "mbuf_ext_pgs size mismatch");
319 * Initialize FreeBSD Network buffer allocation.
322 mbuf_init(void *dummy)
326 * Configure UMA zones for Mbufs, Clusters, and Packets.
328 zone_mbuf = uma_zcreate(MBUF_MEM_NAME, MSIZE,
329 mb_ctor_mbuf, mb_dtor_mbuf, NULL, NULL,
330 MSIZE - 1, UMA_ZONE_CONTIG | UMA_ZONE_MAXBUCKET);
332 nmbufs = uma_zone_set_max(zone_mbuf, nmbufs);
333 uma_zone_set_warning(zone_mbuf, "kern.ipc.nmbufs limit reached");
334 uma_zone_set_maxaction(zone_mbuf, mb_reclaim);
336 zone_clust = uma_zcreate(MBUF_CLUSTER_MEM_NAME, MCLBYTES,
337 mb_ctor_clust, NULL, NULL, NULL,
338 UMA_ALIGN_PTR, UMA_ZONE_CONTIG);
340 nmbclusters = uma_zone_set_max(zone_clust, nmbclusters);
341 uma_zone_set_warning(zone_clust, "kern.ipc.nmbclusters limit reached");
342 uma_zone_set_maxaction(zone_clust, mb_reclaim);
344 zone_pack = uma_zsecond_create(MBUF_PACKET_MEM_NAME, mb_ctor_pack,
345 mb_dtor_pack, mb_zinit_pack, mb_zfini_pack, zone_mbuf);
347 /* Make jumbo frame zone too. Page size, 9k and 16k. */
348 zone_jumbop = uma_zcreate(MBUF_JUMBOP_MEM_NAME, MJUMPAGESIZE,
349 mb_ctor_clust, NULL, NULL, NULL,
350 UMA_ALIGN_PTR, UMA_ZONE_CONTIG);
352 nmbjumbop = uma_zone_set_max(zone_jumbop, nmbjumbop);
353 uma_zone_set_warning(zone_jumbop, "kern.ipc.nmbjumbop limit reached");
354 uma_zone_set_maxaction(zone_jumbop, mb_reclaim);
356 zone_jumbo9 = uma_zcreate(MBUF_JUMBO9_MEM_NAME, MJUM9BYTES,
357 mb_ctor_clust, NULL, NULL, NULL,
358 UMA_ALIGN_PTR, UMA_ZONE_CONTIG);
360 nmbjumbo9 = uma_zone_set_max(zone_jumbo9, nmbjumbo9);
361 uma_zone_set_warning(zone_jumbo9, "kern.ipc.nmbjumbo9 limit reached");
362 uma_zone_set_maxaction(zone_jumbo9, mb_reclaim);
364 zone_jumbo16 = uma_zcreate(MBUF_JUMBO16_MEM_NAME, MJUM16BYTES,
365 mb_ctor_clust, NULL, NULL, NULL,
366 UMA_ALIGN_PTR, UMA_ZONE_CONTIG);
368 nmbjumbo16 = uma_zone_set_max(zone_jumbo16, nmbjumbo16);
369 uma_zone_set_warning(zone_jumbo16, "kern.ipc.nmbjumbo16 limit reached");
370 uma_zone_set_maxaction(zone_jumbo16, mb_reclaim);
372 zone_extpgs = uma_zcreate(MBUF_EXTPGS_MEM_NAME,
373 sizeof(struct mbuf_ext_pgs),
374 NULL, NULL, NULL, NULL,
378 * Hook event handler for low-memory situation, used to
379 * drain protocols and push data back to the caches (UMA
380 * later pushes it back to VM).
382 EVENTHANDLER_REGISTER(vm_lowmem, mb_reclaim, NULL,
383 EVENTHANDLER_PRI_FIRST);
385 snd_tag_count = counter_u64_alloc(M_WAITOK);
387 SYSINIT(mbuf, SI_SUB_MBUF, SI_ORDER_FIRST, mbuf_init, NULL);
391 * debugnet makes use of a pre-allocated pool of mbufs and clusters. When
392 * debugnet is configured, we initialize a set of UMA cache zones which return
393 * items from this pool. At panic-time, the regular UMA zone pointers are
394 * overwritten with those of the cache zones so that drivers may allocate and
395 * free mbufs and clusters without attempting to allocate physical memory.
397 * We keep mbufs and clusters in a pair of mbuf queues. In particular, for
398 * the purpose of caching clusters, we treat them as mbufs.
400 static struct mbufq dn_mbufq =
401 { STAILQ_HEAD_INITIALIZER(dn_mbufq.mq_head), 0, INT_MAX };
402 static struct mbufq dn_clustq =
403 { STAILQ_HEAD_INITIALIZER(dn_clustq.mq_head), 0, INT_MAX };
405 static int dn_clsize;
406 static uma_zone_t dn_zone_mbuf;
407 static uma_zone_t dn_zone_clust;
408 static uma_zone_t dn_zone_pack;
410 static struct debugnet_saved_zones {
412 uma_zone_t dsz_clust;
414 uma_zone_t dsz_jumbop;
415 uma_zone_t dsz_jumbo9;
416 uma_zone_t dsz_jumbo16;
417 bool dsz_debugnet_zones_enabled;
421 dn_buf_import(void *arg, void **store, int count, int domain __unused,
430 for (i = 0; i < count; i++) {
431 m = mbufq_dequeue(q);
434 trash_init(m, q == &dn_mbufq ? MSIZE : dn_clsize, flags);
437 KASSERT((flags & M_WAITOK) == 0 || i == count,
438 ("%s: ran out of pre-allocated mbufs", __func__));
443 dn_buf_release(void *arg, void **store, int count)
451 for (i = 0; i < count; i++) {
453 (void)mbufq_enqueue(q, m);
458 dn_pack_import(void *arg __unused, void **store, int count, int domain __unused,
465 for (i = 0; i < count; i++) {
466 m = m_get(MT_DATA, M_NOWAIT);
469 clust = uma_zalloc(dn_zone_clust, M_NOWAIT);
474 mb_ctor_clust(clust, dn_clsize, m, 0);
477 KASSERT((flags & M_WAITOK) == 0 || i == count,
478 ("%s: ran out of pre-allocated mbufs", __func__));
483 dn_pack_release(void *arg __unused, void **store, int count)
489 for (i = 0; i < count; i++) {
491 clust = m->m_ext.ext_buf;
492 uma_zfree(dn_zone_clust, clust);
493 uma_zfree(dn_zone_mbuf, m);
498 * Free the pre-allocated mbufs and clusters reserved for debugnet, and destroy
499 * the corresponding UMA cache zones.
502 debugnet_mbuf_drain(void)
507 if (dn_zone_mbuf != NULL) {
508 uma_zdestroy(dn_zone_mbuf);
511 if (dn_zone_clust != NULL) {
512 uma_zdestroy(dn_zone_clust);
513 dn_zone_clust = NULL;
515 if (dn_zone_pack != NULL) {
516 uma_zdestroy(dn_zone_pack);
520 while ((m = mbufq_dequeue(&dn_mbufq)) != NULL)
522 while ((item = mbufq_dequeue(&dn_clustq)) != NULL)
523 uma_zfree(m_getzone(dn_clsize), item);
527 * Callback invoked immediately prior to starting a debugnet connection.
530 debugnet_mbuf_start(void)
533 MPASS(!dn_saved_zones.dsz_debugnet_zones_enabled);
535 /* Save the old zone pointers to restore when debugnet is closed. */
536 dn_saved_zones = (struct debugnet_saved_zones) {
537 .dsz_debugnet_zones_enabled = true,
538 .dsz_mbuf = zone_mbuf,
539 .dsz_clust = zone_clust,
540 .dsz_pack = zone_pack,
541 .dsz_jumbop = zone_jumbop,
542 .dsz_jumbo9 = zone_jumbo9,
543 .dsz_jumbo16 = zone_jumbo16,
547 * All cluster zones return buffers of the size requested by the
548 * drivers. It's up to the driver to reinitialize the zones if the
549 * MTU of a debugnet-enabled interface changes.
551 printf("debugnet: overwriting mbuf zone pointers\n");
552 zone_mbuf = dn_zone_mbuf;
553 zone_clust = dn_zone_clust;
554 zone_pack = dn_zone_pack;
555 zone_jumbop = dn_zone_clust;
556 zone_jumbo9 = dn_zone_clust;
557 zone_jumbo16 = dn_zone_clust;
561 * Callback invoked when a debugnet connection is closed/finished.
564 debugnet_mbuf_finish(void)
567 MPASS(dn_saved_zones.dsz_debugnet_zones_enabled);
569 printf("debugnet: restoring mbuf zone pointers\n");
570 zone_mbuf = dn_saved_zones.dsz_mbuf;
571 zone_clust = dn_saved_zones.dsz_clust;
572 zone_pack = dn_saved_zones.dsz_pack;
573 zone_jumbop = dn_saved_zones.dsz_jumbop;
574 zone_jumbo9 = dn_saved_zones.dsz_jumbo9;
575 zone_jumbo16 = dn_saved_zones.dsz_jumbo16;
577 memset(&dn_saved_zones, 0, sizeof(dn_saved_zones));
581 * Reinitialize the debugnet mbuf+cluster pool and cache zones.
584 debugnet_mbuf_reinit(int nmbuf, int nclust, int clsize)
589 debugnet_mbuf_drain();
593 dn_zone_mbuf = uma_zcache_create("debugnet_" MBUF_MEM_NAME,
594 MSIZE, mb_ctor_mbuf, mb_dtor_mbuf, NULL, NULL,
595 dn_buf_import, dn_buf_release,
596 &dn_mbufq, UMA_ZONE_NOBUCKET);
598 dn_zone_clust = uma_zcache_create("debugnet_" MBUF_CLUSTER_MEM_NAME,
599 clsize, mb_ctor_clust, NULL, NULL, NULL,
600 dn_buf_import, dn_buf_release,
601 &dn_clustq, UMA_ZONE_NOBUCKET);
603 dn_zone_pack = uma_zcache_create("debugnet_" MBUF_PACKET_MEM_NAME,
604 MCLBYTES, mb_ctor_pack, mb_dtor_pack, NULL, NULL,
605 dn_pack_import, dn_pack_release,
606 NULL, UMA_ZONE_NOBUCKET);
608 while (nmbuf-- > 0) {
609 m = m_get(MT_DATA, M_WAITOK);
610 uma_zfree(dn_zone_mbuf, m);
612 while (nclust-- > 0) {
613 item = uma_zalloc(m_getzone(dn_clsize), M_WAITOK);
614 uma_zfree(dn_zone_clust, item);
617 #endif /* DEBUGNET */
620 * Constructor for Mbuf master zone.
622 * The 'arg' pointer points to a mb_args structure which
623 * contains call-specific information required to support the
624 * mbuf allocation API. See mbuf.h.
627 mb_ctor_mbuf(void *mem, int size, void *arg, int how)
630 struct mb_args *args;
635 args = (struct mb_args *)arg;
639 * The mbuf is initialized later. The caller has the
640 * responsibility to set up any MAC labels too.
642 if (type == MT_NOINIT)
645 m = (struct mbuf *)mem;
647 MPASS((flags & M_NOFREE) == 0);
649 error = m_init(m, how, type, flags);
655 * The Mbuf master zone destructor.
658 mb_dtor_mbuf(void *mem, int size, void *arg)
663 m = (struct mbuf *)mem;
664 flags = (unsigned long)arg;
666 KASSERT((m->m_flags & M_NOFREE) == 0, ("%s: M_NOFREE set", __func__));
667 if (!(flags & MB_DTOR_SKIP) && (m->m_flags & M_PKTHDR) && !SLIST_EMPTY(&m->m_pkthdr.tags))
668 m_tag_delete_chain(m, NULL);
672 * The Mbuf Packet zone destructor.
675 mb_dtor_pack(void *mem, int size, void *arg)
679 m = (struct mbuf *)mem;
680 if ((m->m_flags & M_PKTHDR) != 0)
681 m_tag_delete_chain(m, NULL);
683 /* Make sure we've got a clean cluster back. */
684 KASSERT((m->m_flags & M_EXT) == M_EXT, ("%s: M_EXT not set", __func__));
685 KASSERT(m->m_ext.ext_buf != NULL, ("%s: ext_buf == NULL", __func__));
686 KASSERT(m->m_ext.ext_free == NULL, ("%s: ext_free != NULL", __func__));
687 KASSERT(m->m_ext.ext_arg1 == NULL, ("%s: ext_arg1 != NULL", __func__));
688 KASSERT(m->m_ext.ext_arg2 == NULL, ("%s: ext_arg2 != NULL", __func__));
689 KASSERT(m->m_ext.ext_size == MCLBYTES, ("%s: ext_size != MCLBYTES", __func__));
690 KASSERT(m->m_ext.ext_type == EXT_PACKET, ("%s: ext_type != EXT_PACKET", __func__));
692 trash_dtor(m->m_ext.ext_buf, MCLBYTES, arg);
695 * If there are processes blocked on zone_clust, waiting for pages
696 * to be freed up, cause them to be woken up by draining the
697 * packet zone. We are exposed to a race here (in the check for
698 * the UMA_ZFLAG_FULL) where we might miss the flag set, but that
699 * is deliberate. We don't want to acquire the zone lock for every
702 if (uma_zone_exhausted(zone_clust))
703 uma_zone_reclaim(zone_pack, UMA_RECLAIM_DRAIN);
707 * The Cluster and Jumbo[PAGESIZE|9|16] zone constructor.
709 * Here the 'arg' pointer points to the Mbuf which we
710 * are configuring cluster storage for. If 'arg' is
711 * empty we allocate just the cluster without setting
712 * the mbuf to it. See mbuf.h.
715 mb_ctor_clust(void *mem, int size, void *arg, int how)
719 m = (struct mbuf *)arg;
721 m->m_ext.ext_buf = (char *)mem;
722 m->m_data = m->m_ext.ext_buf;
724 m->m_ext.ext_free = NULL;
725 m->m_ext.ext_arg1 = NULL;
726 m->m_ext.ext_arg2 = NULL;
727 m->m_ext.ext_size = size;
728 m->m_ext.ext_type = m_gettype(size);
729 m->m_ext.ext_flags = EXT_FLAG_EMBREF;
730 m->m_ext.ext_count = 1;
737 * The Packet secondary zone's init routine, executed on the
738 * object's transition from mbuf keg slab to zone cache.
741 mb_zinit_pack(void *mem, int size, int how)
745 m = (struct mbuf *)mem; /* m is virgin. */
746 if (uma_zalloc_arg(zone_clust, m, how) == NULL ||
747 m->m_ext.ext_buf == NULL)
749 m->m_ext.ext_type = EXT_PACKET; /* Override. */
751 trash_init(m->m_ext.ext_buf, MCLBYTES, how);
757 * The Packet secondary zone's fini routine, executed on the
758 * object's transition from zone cache to keg slab.
761 mb_zfini_pack(void *mem, int size)
765 m = (struct mbuf *)mem;
767 trash_fini(m->m_ext.ext_buf, MCLBYTES);
769 uma_zfree_arg(zone_clust, m->m_ext.ext_buf, NULL);
771 trash_dtor(mem, size, NULL);
776 * The "packet" keg constructor.
779 mb_ctor_pack(void *mem, int size, void *arg, int how)
782 struct mb_args *args;
786 m = (struct mbuf *)mem;
787 args = (struct mb_args *)arg;
790 MPASS((flags & M_NOFREE) == 0);
793 trash_ctor(m->m_ext.ext_buf, MCLBYTES, arg, how);
796 error = m_init(m, how, type, flags);
798 /* m_ext is already initialized. */
799 m->m_data = m->m_ext.ext_buf;
800 m->m_flags = (flags | M_EXT);
806 * This is the protocol drain routine. Called by UMA whenever any of the
807 * mbuf zones is closed to its limit.
809 * No locks should be held when this is called. The drain routines have to
810 * presently acquire some locks which raises the possibility of lock order
814 mb_reclaim(uma_zone_t zone __unused, int pending __unused)
816 struct epoch_tracker et;
820 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK | WARN_PANIC, NULL, __func__);
823 for (dp = domains; dp != NULL; dp = dp->dom_next)
824 for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++)
825 if (pr->pr_drain != NULL)
831 * Free "count" units of I/O from an mbuf chain. They could be held
832 * in EXT_PGS or just as a normal mbuf. This code is intended to be
833 * called in an error path (I/O error, closed connection, etc).
836 mb_free_notready(struct mbuf *m, int count)
840 for (i = 0; i < count && m != NULL; i++) {
841 if ((m->m_flags & M_EXT) != 0 &&
842 m->m_ext.ext_type == EXT_PGS) {
843 m->m_ext.ext_pgs->nrdy--;
844 if (m->m_ext.ext_pgs->nrdy != 0)
849 KASSERT(i == count, ("Removed only %d items from %p", i, m));
853 * Compress an unmapped mbuf into a simple mbuf when it holds a small
854 * amount of data. This is used as a DOS defense to avoid having
855 * small packets tie up wired pages, an ext_pgs structure, and an
856 * mbuf. Since this converts the existing mbuf in place, it can only
857 * be used if there are no other references to 'm'.
860 mb_unmapped_compress(struct mbuf *m)
862 volatile u_int *refcnt;
866 * Assert that 'm' does not have a packet header. If 'm' had
867 * a packet header, it would only be able to hold MHLEN bytes
868 * and m_data would have to be initialized differently.
870 KASSERT((m->m_flags & M_PKTHDR) == 0 && (m->m_flags & M_EXT) &&
871 m->m_ext.ext_type == EXT_PGS,
872 ("%s: m %p !M_EXT or !EXT_PGS or M_PKTHDR", __func__, m));
873 KASSERT(m->m_len <= MLEN, ("m_len too large %p", m));
875 if (m->m_ext.ext_flags & EXT_FLAG_EMBREF) {
876 refcnt = &m->m_ext.ext_count;
878 KASSERT(m->m_ext.ext_cnt != NULL,
879 ("%s: no refcounting pointer on %p", __func__, m));
880 refcnt = m->m_ext.ext_cnt;
887 * Copy mbuf header and m_ext portion of 'm' to 'm_temp' to
888 * create a "fake" EXT_PGS mbuf that can be used with
889 * m_copydata() as well as the ext_free callback.
891 memcpy(&m_temp, m, offsetof(struct mbuf, m_ext) + sizeof (m->m_ext));
892 m_temp.m_next = NULL;
893 m_temp.m_nextpkt = NULL;
895 /* Turn 'm' into a "normal" mbuf. */
896 m->m_flags &= ~(M_EXT | M_RDONLY | M_NOMAP);
897 m->m_data = m->m_dat;
899 /* Copy data from template's ext_pgs. */
900 m_copydata(&m_temp, 0, m_temp.m_len, mtod(m, caddr_t));
902 /* Free the backing pages. */
903 m_temp.m_ext.ext_free(&m_temp);
905 /* Finally, free the ext_pgs struct. */
906 uma_zfree(zone_extpgs, m_temp.m_ext.ext_pgs);
911 * These next few routines are used to permit downgrading an unmapped
912 * mbuf to a chain of mapped mbufs. This is used when an interface
913 * doesn't supported unmapped mbufs or if checksums need to be
914 * computed in software.
916 * Each unmapped mbuf is converted to a chain of mbufs. First, any
917 * TLS header data is stored in a regular mbuf. Second, each page of
918 * unmapped data is stored in an mbuf with an EXT_SFBUF external
919 * cluster. These mbufs use an sf_buf to provide a valid KVA for the
920 * associated physical page. They also hold a reference on the
921 * original EXT_PGS mbuf to ensure the physical page doesn't go away.
922 * Finally, any TLS trailer data is stored in a regular mbuf.
924 * mb_unmapped_free_mext() is the ext_free handler for the EXT_SFBUF
925 * mbufs. It frees the associated sf_buf and releases its reference
926 * on the original EXT_PGS mbuf.
928 * _mb_unmapped_to_ext() is a helper function that converts a single
929 * unmapped mbuf into a chain of mbufs.
931 * mb_unmapped_to_ext() is the public function that walks an mbuf
932 * chain converting any unmapped mbufs to mapped mbufs. It returns
933 * the new chain of unmapped mbufs on success. On failure it frees
934 * the original mbuf chain and returns NULL.
937 mb_unmapped_free_mext(struct mbuf *m)
942 sf = m->m_ext.ext_arg1;
945 /* Drop the reference on the backing EXT_PGS mbuf. */
946 old_m = m->m_ext.ext_arg2;
951 _mb_unmapped_to_ext(struct mbuf *m)
953 struct mbuf_ext_pgs *ext_pgs;
954 struct mbuf *m_new, *top, *prev, *mref;
957 int i, len, off, pglen, pgoff, seglen, segoff;
958 volatile u_int *refcnt;
961 MBUF_EXT_PGS_ASSERT(m);
962 ext_pgs = m->m_ext.ext_pgs;
964 KASSERT(ext_pgs->tls == NULL, ("%s: can't convert TLS mbuf %p",
967 /* See if this is the mbuf that holds the embedded refcount. */
968 if (m->m_ext.ext_flags & EXT_FLAG_EMBREF) {
969 refcnt = &m->m_ext.ext_count;
972 KASSERT(m->m_ext.ext_cnt != NULL,
973 ("%s: no refcounting pointer on %p", __func__, m));
974 refcnt = m->m_ext.ext_cnt;
975 mref = __containerof(refcnt, struct mbuf, m_ext.ext_count);
978 /* Skip over any data removed from the front. */
979 off = mtod(m, vm_offset_t);
982 if (ext_pgs->hdr_len != 0) {
983 if (off >= ext_pgs->hdr_len) {
984 off -= ext_pgs->hdr_len;
986 seglen = ext_pgs->hdr_len - off;
988 seglen = min(seglen, len);
991 m_new = m_get(M_NOWAIT, MT_DATA);
994 m_new->m_len = seglen;
996 memcpy(mtod(m_new, void *), &ext_pgs->hdr[segoff],
1000 pgoff = ext_pgs->first_pg_off;
1001 for (i = 0; i < ext_pgs->npgs && len > 0; i++) {
1002 pglen = mbuf_ext_pg_len(ext_pgs, i, pgoff);
1008 seglen = pglen - off;
1009 segoff = pgoff + off;
1011 seglen = min(seglen, len);
1014 pg = PHYS_TO_VM_PAGE(ext_pgs->pa[i]);
1015 m_new = m_get(M_NOWAIT, MT_DATA);
1021 prev->m_next = m_new;
1024 sf = sf_buf_alloc(pg, SFB_NOWAIT);
1029 m_extadd(m_new, (char *)sf_buf_kva(sf), PAGE_SIZE,
1030 mb_unmapped_free_mext, sf, mref, M_RDONLY, EXT_SFBUF);
1031 m_new->m_data += segoff;
1032 m_new->m_len = seglen;
1037 KASSERT((off + len) <= ext_pgs->trail_len,
1038 ("off + len > trail (%d + %d > %d)", off, len,
1039 ext_pgs->trail_len));
1040 m_new = m_get(M_NOWAIT, MT_DATA);
1046 prev->m_next = m_new;
1048 memcpy(mtod(m_new, void *), &ext_pgs->trail[off], len);
1053 * Obtain an additional reference on the old mbuf for
1054 * each created EXT_SFBUF mbuf. They will be dropped
1055 * in mb_unmapped_free_mext().
1060 atomic_add_int(refcnt, ref_inc);
1068 * Obtain an additional reference on the old mbuf for
1069 * each created EXT_SFBUF mbuf. They will be
1070 * immediately dropped when these mbufs are freed
1076 atomic_add_int(refcnt, ref_inc);
1084 mb_unmapped_to_ext(struct mbuf *top)
1086 struct mbuf *m, *next, *prev = NULL;
1089 for (m = top; m != NULL; m = next) {
1090 /* m might be freed, so cache the next pointer. */
1092 if (m->m_flags & M_NOMAP) {
1095 * Remove 'm' from the new chain so
1096 * that the 'top' chain terminates
1097 * before 'm' in case 'top' is freed
1100 prev->m_next = NULL;
1102 m = _mb_unmapped_to_ext(m);
1115 * Replaced one mbuf with a chain, so we must
1116 * find the end of chain.
1130 * Allocate an empty EXT_PGS mbuf. The ext_free routine is
1131 * responsible for freeing any pages backing this mbuf when it is
1135 mb_alloc_ext_pgs(int how, bool pkthdr, m_ext_free_t ext_free)
1138 struct mbuf_ext_pgs *ext_pgs;
1141 m = m_gethdr(how, MT_DATA);
1143 m = m_get(how, MT_DATA);
1147 ext_pgs = uma_zalloc(zone_extpgs, how);
1148 if (ext_pgs == NULL) {
1154 ext_pgs->first_pg_off = 0;
1155 ext_pgs->last_pg_len = 0;
1157 ext_pgs->hdr_len = 0;
1158 ext_pgs->trail_len = 0;
1159 ext_pgs->tls = NULL;
1162 m->m_flags |= (M_EXT | M_RDONLY | M_NOMAP);
1163 m->m_ext.ext_type = EXT_PGS;
1164 m->m_ext.ext_flags = EXT_FLAG_EMBREF;
1165 m->m_ext.ext_count = 1;
1166 m->m_ext.ext_pgs = ext_pgs;
1167 m->m_ext.ext_size = 0;
1168 m->m_ext.ext_free = ext_free;
1172 #ifdef INVARIANT_SUPPORT
1174 mb_ext_pgs_check(struct mbuf_ext_pgs *ext_pgs)
1178 * NB: This expects a non-empty buffer (npgs > 0 and
1181 KASSERT(ext_pgs->npgs > 0,
1182 ("ext_pgs with no valid pages: %p", ext_pgs));
1183 KASSERT(ext_pgs->npgs <= nitems(ext_pgs->pa),
1184 ("ext_pgs with too many pages: %p", ext_pgs));
1185 KASSERT(ext_pgs->nrdy <= ext_pgs->npgs,
1186 ("ext_pgs with too many ready pages: %p", ext_pgs));
1187 KASSERT(ext_pgs->first_pg_off < PAGE_SIZE,
1188 ("ext_pgs with too large page offset: %p", ext_pgs));
1189 KASSERT(ext_pgs->last_pg_len > 0,
1190 ("ext_pgs with zero last page length: %p", ext_pgs));
1191 KASSERT(ext_pgs->last_pg_len <= PAGE_SIZE,
1192 ("ext_pgs with too large last page length: %p", ext_pgs));
1193 if (ext_pgs->npgs == 1) {
1194 KASSERT(ext_pgs->first_pg_off + ext_pgs->last_pg_len <=
1195 PAGE_SIZE, ("ext_pgs with single page too large: %p",
1198 KASSERT(ext_pgs->hdr_len <= sizeof(ext_pgs->hdr),
1199 ("ext_pgs with too large header length: %p", ext_pgs));
1200 KASSERT(ext_pgs->trail_len <= sizeof(ext_pgs->trail),
1201 ("ext_pgs with too large header length: %p", ext_pgs));
1206 * Clean up after mbufs with M_EXT storage attached to them if the
1207 * reference count hits 1.
1210 mb_free_ext(struct mbuf *m)
1212 volatile u_int *refcnt;
1216 KASSERT(m->m_flags & M_EXT, ("%s: M_EXT not set on %p", __func__, m));
1218 /* See if this is the mbuf that holds the embedded refcount. */
1219 if (m->m_ext.ext_flags & EXT_FLAG_EMBREF) {
1220 refcnt = &m->m_ext.ext_count;
1223 KASSERT(m->m_ext.ext_cnt != NULL,
1224 ("%s: no refcounting pointer on %p", __func__, m));
1225 refcnt = m->m_ext.ext_cnt;
1226 mref = __containerof(refcnt, struct mbuf, m_ext.ext_count);
1230 * Check if the header is embedded in the cluster. It is
1231 * important that we can't touch any of the mbuf fields
1232 * after we have freed the external storage, since mbuf
1233 * could have been embedded in it. For now, the mbufs
1234 * embedded into the cluster are always of type EXT_EXTREF,
1235 * and for this type we won't free the mref.
1237 if (m->m_flags & M_NOFREE) {
1239 KASSERT(m->m_ext.ext_type == EXT_EXTREF ||
1240 m->m_ext.ext_type == EXT_RXRING,
1241 ("%s: no-free mbuf %p has wrong type", __func__, m));
1245 /* Free attached storage if this mbuf is the only reference to it. */
1246 if (*refcnt == 1 || atomic_fetchadd_int(refcnt, -1) == 1) {
1247 switch (m->m_ext.ext_type) {
1249 /* The packet zone is special. */
1252 uma_zfree(zone_pack, mref);
1255 uma_zfree(zone_clust, m->m_ext.ext_buf);
1256 uma_zfree(zone_mbuf, mref);
1259 uma_zfree(zone_jumbop, m->m_ext.ext_buf);
1260 uma_zfree(zone_mbuf, mref);
1263 uma_zfree(zone_jumbo9, m->m_ext.ext_buf);
1264 uma_zfree(zone_mbuf, mref);
1267 uma_zfree(zone_jumbo16, m->m_ext.ext_buf);
1268 uma_zfree(zone_mbuf, mref);
1272 struct mbuf_ext_pgs *pgs;
1273 struct ktls_session *tls;
1276 KASSERT(mref->m_ext.ext_free != NULL,
1277 ("%s: ext_free not set", __func__));
1278 mref->m_ext.ext_free(mref);
1280 pgs = mref->m_ext.ext_pgs;
1283 !refcount_release_if_not_last(&tls->refcount))
1284 ktls_enqueue_to_free(pgs);
1287 uma_zfree(zone_extpgs, mref->m_ext.ext_pgs);
1288 uma_zfree(zone_mbuf, mref);
1294 case EXT_DISPOSABLE:
1295 KASSERT(mref->m_ext.ext_free != NULL,
1296 ("%s: ext_free not set", __func__));
1297 mref->m_ext.ext_free(mref);
1298 uma_zfree(zone_mbuf, mref);
1301 KASSERT(m->m_ext.ext_free != NULL,
1302 ("%s: ext_free not set", __func__));
1303 m->m_ext.ext_free(m);
1306 KASSERT(m->m_ext.ext_free == NULL,
1307 ("%s: ext_free is set", __func__));
1310 KASSERT(m->m_ext.ext_type == 0,
1311 ("%s: unknown ext_type", __func__));
1315 if (freembuf && m != mref)
1316 uma_zfree(zone_mbuf, m);
1320 * Official mbuf(9) allocation KPI for stack and drivers:
1322 * m_get() - a single mbuf without any attachments, sys/mbuf.h.
1323 * m_gethdr() - a single mbuf initialized as M_PKTHDR, sys/mbuf.h.
1324 * m_getcl() - an mbuf + 2k cluster, sys/mbuf.h.
1325 * m_clget() - attach cluster to already allocated mbuf.
1326 * m_cljget() - attach jumbo cluster to already allocated mbuf.
1327 * m_get2() - allocate minimum mbuf that would fit size argument.
1328 * m_getm2() - allocate a chain of mbufs/clusters.
1329 * m_extadd() - attach external cluster to mbuf.
1331 * m_free() - free single mbuf with its tags and ext, sys/mbuf.h.
1332 * m_freem() - free chain of mbufs.
1336 m_clget(struct mbuf *m, int how)
1339 KASSERT((m->m_flags & M_EXT) == 0, ("%s: mbuf %p has M_EXT",
1341 m->m_ext.ext_buf = (char *)NULL;
1342 uma_zalloc_arg(zone_clust, m, how);
1344 * On a cluster allocation failure, drain the packet zone and retry,
1345 * we might be able to loosen a few clusters up on the drain.
1347 if ((how & M_NOWAIT) && (m->m_ext.ext_buf == NULL)) {
1348 uma_zone_reclaim(zone_pack, UMA_RECLAIM_DRAIN);
1349 uma_zalloc_arg(zone_clust, m, how);
1351 MBUF_PROBE2(m__clget, m, how);
1352 return (m->m_flags & M_EXT);
1356 * m_cljget() is different from m_clget() as it can allocate clusters without
1357 * attaching them to an mbuf. In that case the return value is the pointer
1358 * to the cluster of the requested size. If an mbuf was specified, it gets
1359 * the cluster attached to it and the return value can be safely ignored.
1360 * For size it takes MCLBYTES, MJUMPAGESIZE, MJUM9BYTES, MJUM16BYTES.
1363 m_cljget(struct mbuf *m, int how, int size)
1369 KASSERT((m->m_flags & M_EXT) == 0, ("%s: mbuf %p has M_EXT",
1371 m->m_ext.ext_buf = NULL;
1374 zone = m_getzone(size);
1375 retval = uma_zalloc_arg(zone, m, how);
1377 MBUF_PROBE4(m__cljget, m, how, size, retval);
1383 * m_get2() allocates minimum mbuf that would fit "size" argument.
1386 m_get2(int size, int how, short type, int flags)
1388 struct mb_args args;
1394 if (size <= MHLEN || (size <= MLEN && (flags & M_PKTHDR) == 0))
1395 return (uma_zalloc_arg(zone_mbuf, &args, how));
1396 if (size <= MCLBYTES)
1397 return (uma_zalloc_arg(zone_pack, &args, how));
1399 if (size > MJUMPAGESIZE)
1402 m = uma_zalloc_arg(zone_mbuf, &args, how);
1406 n = uma_zalloc_arg(zone_jumbop, m, how);
1408 uma_zfree(zone_mbuf, m);
1416 * m_getjcl() returns an mbuf with a cluster of the specified size attached.
1417 * For size it takes MCLBYTES, MJUMPAGESIZE, MJUM9BYTES, MJUM16BYTES.
1420 m_getjcl(int how, short type, int flags, int size)
1422 struct mb_args args;
1426 if (size == MCLBYTES)
1427 return m_getcl(how, type, flags);
1432 m = uma_zalloc_arg(zone_mbuf, &args, how);
1436 zone = m_getzone(size);
1437 n = uma_zalloc_arg(zone, m, how);
1439 uma_zfree(zone_mbuf, m);
1446 * Allocate a given length worth of mbufs and/or clusters (whatever fits
1447 * best) and return a pointer to the top of the allocated chain. If an
1448 * existing mbuf chain is provided, then we will append the new chain
1449 * to the existing one and return a pointer to the provided mbuf.
1452 m_getm2(struct mbuf *m, int len, int how, short type, int flags)
1454 struct mbuf *mb, *nm = NULL, *mtail = NULL;
1456 KASSERT(len >= 0, ("%s: len is < 0", __func__));
1458 /* Validate flags. */
1459 flags &= (M_PKTHDR | M_EOR);
1461 /* Packet header mbuf must be first in chain. */
1462 if ((flags & M_PKTHDR) && m != NULL)
1465 /* Loop and append maximum sized mbufs to the chain tail. */
1468 mb = m_getjcl(how, type, (flags & M_PKTHDR),
1470 else if (len >= MINCLSIZE)
1471 mb = m_getcl(how, type, (flags & M_PKTHDR));
1472 else if (flags & M_PKTHDR)
1473 mb = m_gethdr(how, type);
1475 mb = m_get(how, type);
1477 /* Fail the whole operation if one mbuf can't be allocated. */
1491 flags &= ~M_PKTHDR; /* Only valid on the first mbuf. */
1494 mtail->m_flags |= M_EOR; /* Only valid on the last mbuf. */
1496 /* If mbuf was supplied, append new chain to the end of it. */
1498 for (mtail = m; mtail->m_next != NULL; mtail = mtail->m_next)
1501 mtail->m_flags &= ~M_EOR;
1509 * Configure a provided mbuf to refer to the provided external storage
1510 * buffer and setup a reference count for said buffer.
1513 * mb The existing mbuf to which to attach the provided buffer.
1514 * buf The address of the provided external storage buffer.
1515 * size The size of the provided buffer.
1516 * freef A pointer to a routine that is responsible for freeing the
1517 * provided external storage buffer.
1518 * args A pointer to an argument structure (of any type) to be passed
1519 * to the provided freef routine (may be NULL).
1520 * flags Any other flags to be passed to the provided mbuf.
1521 * type The type that the external storage buffer should be
1528 m_extadd(struct mbuf *mb, char *buf, u_int size, m_ext_free_t freef,
1529 void *arg1, void *arg2, int flags, int type)
1532 KASSERT(type != EXT_CLUSTER, ("%s: EXT_CLUSTER not allowed", __func__));
1534 mb->m_flags |= (M_EXT | flags);
1535 mb->m_ext.ext_buf = buf;
1536 mb->m_data = mb->m_ext.ext_buf;
1537 mb->m_ext.ext_size = size;
1538 mb->m_ext.ext_free = freef;
1539 mb->m_ext.ext_arg1 = arg1;
1540 mb->m_ext.ext_arg2 = arg2;
1541 mb->m_ext.ext_type = type;
1543 if (type != EXT_EXTREF) {
1544 mb->m_ext.ext_count = 1;
1545 mb->m_ext.ext_flags = EXT_FLAG_EMBREF;
1547 mb->m_ext.ext_flags = 0;
1551 * Free an entire chain of mbufs and associated external buffers, if
1555 m_freem(struct mbuf *mb)
1558 MBUF_PROBE1(m__freem, mb);
1564 m_snd_tag_init(struct m_snd_tag *mst, struct ifnet *ifp)
1569 refcount_init(&mst->refcount, 1);
1570 counter_u64_add(snd_tag_count, 1);
1574 m_snd_tag_destroy(struct m_snd_tag *mst)
1579 ifp->if_snd_tag_free(mst);
1581 counter_u64_add(snd_tag_count, -1);