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"
35 #include <sys/param.h>
37 #include <sys/malloc.h>
38 #include <sys/systm.h>
40 #include <sys/domain.h>
41 #include <sys/eventhandler.h>
42 #include <sys/kernel.h>
43 #include <sys/limits.h>
45 #include <sys/mutex.h>
46 #include <sys/protosw.h>
48 #include <sys/sysctl.h>
51 #include <vm/vm_extern.h>
52 #include <vm/vm_kern.h>
53 #include <vm/vm_page.h>
54 #include <vm/vm_map.h>
56 #include <vm/uma_dbg.h>
59 * In FreeBSD, Mbufs and Mbuf Clusters are allocated from UMA
62 * Mbuf Clusters (2K, contiguous) are allocated from the Cluster
63 * Zone. The Zone can be capped at kern.ipc.nmbclusters, if the
64 * administrator so desires.
66 * Mbufs are allocated from a UMA Master Zone called the Mbuf
69 * Additionally, FreeBSD provides a Packet Zone, which it
70 * configures as a Secondary Zone to the Mbuf Master Zone,
71 * thus sharing backend Slab kegs with the Mbuf Master Zone.
73 * Thus common-case allocations and locking are simplified:
77 * | .------------>[(Packet Cache)] m_get(), m_gethdr()
79 * [(Cluster Cache)] [ Secondary ] [ (Mbuf Cache) ]
80 * [ Cluster Zone ] [ Zone ] [ Mbuf Master Zone ]
86 * \____________(VM)_________________/
89 * Whenever an object is allocated with uma_zalloc() out of
90 * one of the Zones its _ctor_ function is executed. The same
91 * for any deallocation through uma_zfree() the _dtor_ function
94 * Caches are per-CPU and are filled from the Master Zone.
96 * Whenever an object is allocated from the underlying global
97 * memory pool it gets pre-initialized with the _zinit_ functions.
98 * When the Keg's are overfull objects get decommissioned with
99 * _zfini_ functions and free'd back to the global memory pool.
103 int nmbufs; /* limits number of mbufs */
104 int nmbclusters; /* limits number of mbuf clusters */
105 int nmbjumbop; /* limits number of page size jumbo clusters */
106 int nmbjumbo9; /* limits number of 9k jumbo clusters */
107 int nmbjumbo16; /* limits number of 16k jumbo clusters */
109 static quad_t maxmbufmem; /* overall real memory limit for all mbufs */
111 SYSCTL_QUAD(_kern_ipc, OID_AUTO, maxmbufmem, CTLFLAG_RDTUN | CTLFLAG_NOFETCH, &maxmbufmem, 0,
112 "Maximum real memory allocatable to various mbuf types");
115 * tunable_mbinit() has to be run before any mbuf allocations are done.
118 tunable_mbinit(void *dummy)
123 * The default limit for all mbuf related memory is 1/2 of all
124 * available kernel memory (physical or kmem).
125 * At most it can be 3/4 of available kernel memory.
127 realmem = qmin((quad_t)physmem * PAGE_SIZE, vm_kmem_size);
128 maxmbufmem = realmem / 2;
129 TUNABLE_QUAD_FETCH("kern.ipc.maxmbufmem", &maxmbufmem);
130 if (maxmbufmem > realmem / 4 * 3)
131 maxmbufmem = realmem / 4 * 3;
133 TUNABLE_INT_FETCH("kern.ipc.nmbclusters", &nmbclusters);
134 if (nmbclusters == 0)
135 nmbclusters = maxmbufmem / MCLBYTES / 4;
137 TUNABLE_INT_FETCH("kern.ipc.nmbjumbop", &nmbjumbop);
139 nmbjumbop = maxmbufmem / MJUMPAGESIZE / 4;
141 TUNABLE_INT_FETCH("kern.ipc.nmbjumbo9", &nmbjumbo9);
143 nmbjumbo9 = maxmbufmem / MJUM9BYTES / 6;
145 TUNABLE_INT_FETCH("kern.ipc.nmbjumbo16", &nmbjumbo16);
147 nmbjumbo16 = maxmbufmem / MJUM16BYTES / 6;
150 * We need at least as many mbufs as we have clusters of
151 * the various types added together.
153 TUNABLE_INT_FETCH("kern.ipc.nmbufs", &nmbufs);
154 if (nmbufs < nmbclusters + nmbjumbop + nmbjumbo9 + nmbjumbo16)
155 nmbufs = lmax(maxmbufmem / MSIZE / 5,
156 nmbclusters + nmbjumbop + nmbjumbo9 + nmbjumbo16);
158 SYSINIT(tunable_mbinit, SI_SUB_KMEM, SI_ORDER_MIDDLE, tunable_mbinit, NULL);
161 sysctl_nmbclusters(SYSCTL_HANDLER_ARGS)
163 int error, newnmbclusters;
165 newnmbclusters = nmbclusters;
166 error = sysctl_handle_int(oidp, &newnmbclusters, 0, req);
167 if (error == 0 && req->newptr && newnmbclusters != nmbclusters) {
168 if (newnmbclusters > nmbclusters &&
169 nmbufs >= nmbclusters + nmbjumbop + nmbjumbo9 + nmbjumbo16) {
170 nmbclusters = newnmbclusters;
171 nmbclusters = uma_zone_set_max(zone_clust, nmbclusters);
172 EVENTHANDLER_INVOKE(nmbclusters_change);
178 SYSCTL_PROC(_kern_ipc, OID_AUTO, nmbclusters, CTLTYPE_INT|CTLFLAG_RW,
179 &nmbclusters, 0, sysctl_nmbclusters, "IU",
180 "Maximum number of mbuf clusters allowed");
183 sysctl_nmbjumbop(SYSCTL_HANDLER_ARGS)
185 int error, newnmbjumbop;
187 newnmbjumbop = nmbjumbop;
188 error = sysctl_handle_int(oidp, &newnmbjumbop, 0, req);
189 if (error == 0 && req->newptr && newnmbjumbop != nmbjumbop) {
190 if (newnmbjumbop > nmbjumbop &&
191 nmbufs >= nmbclusters + nmbjumbop + nmbjumbo9 + nmbjumbo16) {
192 nmbjumbop = newnmbjumbop;
193 nmbjumbop = uma_zone_set_max(zone_jumbop, nmbjumbop);
199 SYSCTL_PROC(_kern_ipc, OID_AUTO, nmbjumbop, CTLTYPE_INT|CTLFLAG_RW,
200 &nmbjumbop, 0, sysctl_nmbjumbop, "IU",
201 "Maximum number of mbuf page size jumbo clusters allowed");
204 sysctl_nmbjumbo9(SYSCTL_HANDLER_ARGS)
206 int error, newnmbjumbo9;
208 newnmbjumbo9 = nmbjumbo9;
209 error = sysctl_handle_int(oidp, &newnmbjumbo9, 0, req);
210 if (error == 0 && req->newptr && newnmbjumbo9 != nmbjumbo9) {
211 if (newnmbjumbo9 > nmbjumbo9 &&
212 nmbufs >= nmbclusters + nmbjumbop + nmbjumbo9 + nmbjumbo16) {
213 nmbjumbo9 = newnmbjumbo9;
214 nmbjumbo9 = uma_zone_set_max(zone_jumbo9, nmbjumbo9);
220 SYSCTL_PROC(_kern_ipc, OID_AUTO, nmbjumbo9, CTLTYPE_INT|CTLFLAG_RW,
221 &nmbjumbo9, 0, sysctl_nmbjumbo9, "IU",
222 "Maximum number of mbuf 9k jumbo clusters allowed");
225 sysctl_nmbjumbo16(SYSCTL_HANDLER_ARGS)
227 int error, newnmbjumbo16;
229 newnmbjumbo16 = nmbjumbo16;
230 error = sysctl_handle_int(oidp, &newnmbjumbo16, 0, req);
231 if (error == 0 && req->newptr && newnmbjumbo16 != nmbjumbo16) {
232 if (newnmbjumbo16 > nmbjumbo16 &&
233 nmbufs >= nmbclusters + nmbjumbop + nmbjumbo9 + nmbjumbo16) {
234 nmbjumbo16 = newnmbjumbo16;
235 nmbjumbo16 = uma_zone_set_max(zone_jumbo16, nmbjumbo16);
241 SYSCTL_PROC(_kern_ipc, OID_AUTO, nmbjumbo16, CTLTYPE_INT|CTLFLAG_RW,
242 &nmbjumbo16, 0, sysctl_nmbjumbo16, "IU",
243 "Maximum number of mbuf 16k jumbo clusters allowed");
246 sysctl_nmbufs(SYSCTL_HANDLER_ARGS)
248 int error, newnmbufs;
251 error = sysctl_handle_int(oidp, &newnmbufs, 0, req);
252 if (error == 0 && req->newptr && newnmbufs != nmbufs) {
253 if (newnmbufs > nmbufs) {
255 nmbufs = uma_zone_set_max(zone_mbuf, nmbufs);
256 EVENTHANDLER_INVOKE(nmbufs_change);
262 SYSCTL_PROC(_kern_ipc, OID_AUTO, nmbufs, CTLTYPE_INT|CTLFLAG_RW,
263 &nmbufs, 0, sysctl_nmbufs, "IU",
264 "Maximum number of mbufs allowed");
267 * Zones from which we allocate.
269 uma_zone_t zone_mbuf;
270 uma_zone_t zone_clust;
271 uma_zone_t zone_pack;
272 uma_zone_t zone_jumbop;
273 uma_zone_t zone_jumbo9;
274 uma_zone_t zone_jumbo16;
279 static int mb_ctor_mbuf(void *, int, void *, int);
280 static int mb_ctor_clust(void *, int, void *, int);
281 static int mb_ctor_pack(void *, int, void *, int);
282 static void mb_dtor_mbuf(void *, int, void *);
283 static void mb_dtor_pack(void *, int, void *);
284 static int mb_zinit_pack(void *, int, int);
285 static void mb_zfini_pack(void *, int);
286 static void mb_reclaim(uma_zone_t, int);
287 static void *mbuf_jumbo_alloc(uma_zone_t, vm_size_t, int, uint8_t *, int);
289 /* Ensure that MSIZE is a power of 2. */
290 CTASSERT((((MSIZE - 1) ^ MSIZE) + 1) >> 1 == MSIZE);
293 * Initialize FreeBSD Network buffer allocation.
296 mbuf_init(void *dummy)
300 * Configure UMA zones for Mbufs, Clusters, and Packets.
302 zone_mbuf = uma_zcreate(MBUF_MEM_NAME, MSIZE,
303 mb_ctor_mbuf, mb_dtor_mbuf,
305 trash_init, trash_fini,
309 MSIZE - 1, UMA_ZONE_MAXBUCKET);
311 nmbufs = uma_zone_set_max(zone_mbuf, nmbufs);
312 uma_zone_set_warning(zone_mbuf, "kern.ipc.nmbufs limit reached");
313 uma_zone_set_maxaction(zone_mbuf, mb_reclaim);
315 zone_clust = uma_zcreate(MBUF_CLUSTER_MEM_NAME, MCLBYTES,
318 trash_dtor, trash_init, trash_fini,
324 nmbclusters = uma_zone_set_max(zone_clust, nmbclusters);
325 uma_zone_set_warning(zone_clust, "kern.ipc.nmbclusters limit reached");
326 uma_zone_set_maxaction(zone_clust, mb_reclaim);
328 zone_pack = uma_zsecond_create(MBUF_PACKET_MEM_NAME, mb_ctor_pack,
329 mb_dtor_pack, mb_zinit_pack, mb_zfini_pack, zone_mbuf);
331 /* Make jumbo frame zone too. Page size, 9k and 16k. */
332 zone_jumbop = uma_zcreate(MBUF_JUMBOP_MEM_NAME, MJUMPAGESIZE,
335 trash_dtor, trash_init, trash_fini,
341 nmbjumbop = uma_zone_set_max(zone_jumbop, nmbjumbop);
342 uma_zone_set_warning(zone_jumbop, "kern.ipc.nmbjumbop limit reached");
343 uma_zone_set_maxaction(zone_jumbop, mb_reclaim);
345 zone_jumbo9 = uma_zcreate(MBUF_JUMBO9_MEM_NAME, MJUM9BYTES,
348 trash_dtor, trash_init, trash_fini,
353 uma_zone_set_allocf(zone_jumbo9, mbuf_jumbo_alloc);
355 nmbjumbo9 = uma_zone_set_max(zone_jumbo9, nmbjumbo9);
356 uma_zone_set_warning(zone_jumbo9, "kern.ipc.nmbjumbo9 limit reached");
357 uma_zone_set_maxaction(zone_jumbo9, mb_reclaim);
359 zone_jumbo16 = uma_zcreate(MBUF_JUMBO16_MEM_NAME, MJUM16BYTES,
362 trash_dtor, trash_init, trash_fini,
367 uma_zone_set_allocf(zone_jumbo16, mbuf_jumbo_alloc);
369 nmbjumbo16 = uma_zone_set_max(zone_jumbo16, nmbjumbo16);
370 uma_zone_set_warning(zone_jumbo16, "kern.ipc.nmbjumbo16 limit reached");
371 uma_zone_set_maxaction(zone_jumbo16, mb_reclaim);
374 * Hook event handler for low-memory situation, used to
375 * drain protocols and push data back to the caches (UMA
376 * later pushes it back to VM).
378 EVENTHANDLER_REGISTER(vm_lowmem, mb_reclaim, NULL,
379 EVENTHANDLER_PRI_FIRST);
381 SYSINIT(mbuf, SI_SUB_MBUF, SI_ORDER_FIRST, mbuf_init, NULL);
385 * netdump makes use of a pre-allocated pool of mbufs and clusters. When
386 * netdump is configured, we initialize a set of UMA cache zones which return
387 * items from this pool. At panic-time, the regular UMA zone pointers are
388 * overwritten with those of the cache zones so that drivers may allocate and
389 * free mbufs and clusters without attempting to allocate physical memory.
391 * We keep mbufs and clusters in a pair of mbuf queues. In particular, for
392 * the purpose of caching clusters, we treat them as mbufs.
394 static struct mbufq nd_mbufq =
395 { STAILQ_HEAD_INITIALIZER(nd_mbufq.mq_head), 0, INT_MAX };
396 static struct mbufq nd_clustq =
397 { STAILQ_HEAD_INITIALIZER(nd_clustq.mq_head), 0, INT_MAX };
399 static int nd_clsize;
400 static uma_zone_t nd_zone_mbuf;
401 static uma_zone_t nd_zone_clust;
402 static uma_zone_t nd_zone_pack;
405 nd_buf_import(void *arg, void **store, int count, int domain __unused,
412 KASSERT(!dumping, ("%s: ran out of pre-allocated mbufs", __func__));
416 for (i = 0; i < count; i++) {
417 m = mbufq_dequeue(q);
420 trash_init(m, q == &nd_mbufq ? MSIZE : nd_clsize, flags);
427 nd_buf_release(void *arg, void **store, int count)
435 for (i = 0; i < count; i++) {
437 (void)mbufq_enqueue(q, m);
442 nd_pack_import(void *arg __unused, void **store, int count, int domain __unused,
449 KASSERT(!dumping, ("%s: ran out of pre-allocated mbufs", __func__));
451 for (i = 0; i < count; i++) {
452 m = m_get(MT_DATA, M_NOWAIT);
455 clust = uma_zalloc(nd_zone_clust, M_NOWAIT);
460 mb_ctor_clust(clust, nd_clsize, m, 0);
467 nd_pack_release(void *arg __unused, void **store, int count)
473 for (i = 0; i < count; i++) {
475 clust = m->m_ext.ext_buf;
476 uma_zfree(nd_zone_clust, clust);
477 uma_zfree(nd_zone_mbuf, m);
482 * Free the pre-allocated mbufs and clusters reserved for netdump, and destroy
483 * the corresponding UMA cache zones.
486 netdump_mbuf_drain(void)
491 if (nd_zone_mbuf != NULL) {
492 uma_zdestroy(nd_zone_mbuf);
495 if (nd_zone_clust != NULL) {
496 uma_zdestroy(nd_zone_clust);
497 nd_zone_clust = NULL;
499 if (nd_zone_pack != NULL) {
500 uma_zdestroy(nd_zone_pack);
504 while ((m = mbufq_dequeue(&nd_mbufq)) != NULL)
506 while ((item = mbufq_dequeue(&nd_clustq)) != NULL)
507 uma_zfree(m_getzone(nd_clsize), item);
511 * Callback invoked immediately prior to starting a netdump.
514 netdump_mbuf_dump(void)
518 * All cluster zones return buffers of the size requested by the
519 * drivers. It's up to the driver to reinitialize the zones if the
520 * MTU of a netdump-enabled interface changes.
522 printf("netdump: overwriting mbuf zone pointers\n");
523 zone_mbuf = nd_zone_mbuf;
524 zone_clust = nd_zone_clust;
525 zone_pack = nd_zone_pack;
526 zone_jumbop = nd_zone_clust;
527 zone_jumbo9 = nd_zone_clust;
528 zone_jumbo16 = nd_zone_clust;
532 * Reinitialize the netdump mbuf+cluster pool and cache zones.
535 netdump_mbuf_reinit(int nmbuf, int nclust, int clsize)
540 netdump_mbuf_drain();
544 nd_zone_mbuf = uma_zcache_create("netdump_" MBUF_MEM_NAME,
545 MSIZE, mb_ctor_mbuf, mb_dtor_mbuf,
547 trash_init, trash_fini,
551 nd_buf_import, nd_buf_release,
552 &nd_mbufq, UMA_ZONE_NOBUCKET);
554 nd_zone_clust = uma_zcache_create("netdump_" MBUF_CLUSTER_MEM_NAME,
555 clsize, mb_ctor_clust,
557 trash_dtor, trash_init, trash_fini,
561 nd_buf_import, nd_buf_release,
562 &nd_clustq, UMA_ZONE_NOBUCKET);
564 nd_zone_pack = uma_zcache_create("netdump_" MBUF_PACKET_MEM_NAME,
565 MCLBYTES, mb_ctor_pack, mb_dtor_pack, NULL, NULL,
566 nd_pack_import, nd_pack_release,
567 NULL, UMA_ZONE_NOBUCKET);
569 while (nmbuf-- > 0) {
570 m = m_get(MT_DATA, M_WAITOK);
571 uma_zfree(nd_zone_mbuf, m);
573 while (nclust-- > 0) {
574 item = uma_zalloc(m_getzone(nd_clsize), M_WAITOK);
575 uma_zfree(nd_zone_clust, item);
581 * UMA backend page allocator for the jumbo frame zones.
583 * Allocates kernel virtual memory that is backed by contiguous physical
587 mbuf_jumbo_alloc(uma_zone_t zone, vm_size_t bytes, int domain, uint8_t *flags,
591 /* Inform UMA that this allocator uses kernel_map/object. */
592 *flags = UMA_SLAB_KERNEL;
593 return ((void *)kmem_alloc_contig_domain(domain, bytes, wait,
594 (vm_paddr_t)0, ~(vm_paddr_t)0, 1, 0, VM_MEMATTR_DEFAULT));
598 * Constructor for Mbuf master zone.
600 * The 'arg' pointer points to a mb_args structure which
601 * contains call-specific information required to support the
602 * mbuf allocation API. See mbuf.h.
605 mb_ctor_mbuf(void *mem, int size, void *arg, int how)
608 struct mb_args *args;
614 trash_ctor(mem, size, arg, how);
616 args = (struct mb_args *)arg;
620 * The mbuf is initialized later. The caller has the
621 * responsibility to set up any MAC labels too.
623 if (type == MT_NOINIT)
626 m = (struct mbuf *)mem;
628 MPASS((flags & M_NOFREE) == 0);
630 error = m_init(m, how, type, flags);
636 * The Mbuf master zone destructor.
639 mb_dtor_mbuf(void *mem, int size, void *arg)
644 m = (struct mbuf *)mem;
645 flags = (unsigned long)arg;
647 KASSERT((m->m_flags & M_NOFREE) == 0, ("%s: M_NOFREE set", __func__));
648 if (!(flags & MB_DTOR_SKIP) && (m->m_flags & M_PKTHDR) && !SLIST_EMPTY(&m->m_pkthdr.tags))
649 m_tag_delete_chain(m, NULL);
651 trash_dtor(mem, size, arg);
656 * The Mbuf Packet zone destructor.
659 mb_dtor_pack(void *mem, int size, void *arg)
663 m = (struct mbuf *)mem;
664 if ((m->m_flags & M_PKTHDR) != 0)
665 m_tag_delete_chain(m, NULL);
667 /* Make sure we've got a clean cluster back. */
668 KASSERT((m->m_flags & M_EXT) == M_EXT, ("%s: M_EXT not set", __func__));
669 KASSERT(m->m_ext.ext_buf != NULL, ("%s: ext_buf == NULL", __func__));
670 KASSERT(m->m_ext.ext_free == NULL, ("%s: ext_free != NULL", __func__));
671 KASSERT(m->m_ext.ext_arg1 == NULL, ("%s: ext_arg1 != NULL", __func__));
672 KASSERT(m->m_ext.ext_arg2 == NULL, ("%s: ext_arg2 != NULL", __func__));
673 KASSERT(m->m_ext.ext_size == MCLBYTES, ("%s: ext_size != MCLBYTES", __func__));
674 KASSERT(m->m_ext.ext_type == EXT_PACKET, ("%s: ext_type != EXT_PACKET", __func__));
676 trash_dtor(m->m_ext.ext_buf, MCLBYTES, arg);
679 * If there are processes blocked on zone_clust, waiting for pages
680 * to be freed up, * cause them to be woken up by draining the
681 * packet zone. We are exposed to a race here * (in the check for
682 * the UMA_ZFLAG_FULL) where we might miss the flag set, but that
683 * is deliberate. We don't want to acquire the zone lock for every
686 if (uma_zone_exhausted_nolock(zone_clust))
687 zone_drain(zone_pack);
691 * The Cluster and Jumbo[PAGESIZE|9|16] zone constructor.
693 * Here the 'arg' pointer points to the Mbuf which we
694 * are configuring cluster storage for. If 'arg' is
695 * empty we allocate just the cluster without setting
696 * the mbuf to it. See mbuf.h.
699 mb_ctor_clust(void *mem, int size, void *arg, int how)
704 trash_ctor(mem, size, arg, how);
706 m = (struct mbuf *)arg;
708 m->m_ext.ext_buf = (char *)mem;
709 m->m_data = m->m_ext.ext_buf;
711 m->m_ext.ext_free = NULL;
712 m->m_ext.ext_arg1 = NULL;
713 m->m_ext.ext_arg2 = NULL;
714 m->m_ext.ext_size = size;
715 m->m_ext.ext_type = m_gettype(size);
716 m->m_ext.ext_flags = EXT_FLAG_EMBREF;
717 m->m_ext.ext_count = 1;
724 * The Packet secondary zone's init routine, executed on the
725 * object's transition from mbuf keg slab to zone cache.
728 mb_zinit_pack(void *mem, int size, int how)
732 m = (struct mbuf *)mem; /* m is virgin. */
733 if (uma_zalloc_arg(zone_clust, m, how) == NULL ||
734 m->m_ext.ext_buf == NULL)
736 m->m_ext.ext_type = EXT_PACKET; /* Override. */
738 trash_init(m->m_ext.ext_buf, MCLBYTES, how);
744 * The Packet secondary zone's fini routine, executed on the
745 * object's transition from zone cache to keg slab.
748 mb_zfini_pack(void *mem, int size)
752 m = (struct mbuf *)mem;
754 trash_fini(m->m_ext.ext_buf, MCLBYTES);
756 uma_zfree_arg(zone_clust, m->m_ext.ext_buf, NULL);
758 trash_dtor(mem, size, NULL);
763 * The "packet" keg constructor.
766 mb_ctor_pack(void *mem, int size, void *arg, int how)
769 struct mb_args *args;
773 m = (struct mbuf *)mem;
774 args = (struct mb_args *)arg;
777 MPASS((flags & M_NOFREE) == 0);
780 trash_ctor(m->m_ext.ext_buf, MCLBYTES, arg, how);
783 error = m_init(m, how, type, flags);
785 /* m_ext is already initialized. */
786 m->m_data = m->m_ext.ext_buf;
787 m->m_flags = (flags | M_EXT);
793 * This is the protocol drain routine. Called by UMA whenever any of the
794 * mbuf zones is closed to its limit.
796 * No locks should be held when this is called. The drain routines have to
797 * presently acquire some locks which raises the possibility of lock order
801 mb_reclaim(uma_zone_t zone __unused, int pending __unused)
806 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK | WARN_PANIC, NULL, __func__);
808 for (dp = domains; dp != NULL; dp = dp->dom_next)
809 for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++)
810 if (pr->pr_drain != NULL)
815 * Clean up after mbufs with M_EXT storage attached to them if the
816 * reference count hits 1.
819 mb_free_ext(struct mbuf *m)
821 volatile u_int *refcnt;
825 KASSERT(m->m_flags & M_EXT, ("%s: M_EXT not set on %p", __func__, m));
827 /* See if this is the mbuf that holds the embedded refcount. */
828 if (m->m_ext.ext_flags & EXT_FLAG_EMBREF) {
829 refcnt = &m->m_ext.ext_count;
832 KASSERT(m->m_ext.ext_cnt != NULL,
833 ("%s: no refcounting pointer on %p", __func__, m));
834 refcnt = m->m_ext.ext_cnt;
835 mref = __containerof(refcnt, struct mbuf, m_ext.ext_count);
839 * Check if the header is embedded in the cluster. It is
840 * important that we can't touch any of the mbuf fields
841 * after we have freed the external storage, since mbuf
842 * could have been embedded in it. For now, the mbufs
843 * embedded into the cluster are always of type EXT_EXTREF,
844 * and for this type we won't free the mref.
846 if (m->m_flags & M_NOFREE) {
848 KASSERT(m->m_ext.ext_type == EXT_EXTREF,
849 ("%s: no-free mbuf %p has wrong type", __func__, m));
853 /* Free attached storage if this mbuf is the only reference to it. */
854 if (*refcnt == 1 || atomic_fetchadd_int(refcnt, -1) == 1) {
855 switch (m->m_ext.ext_type) {
857 /* The packet zone is special. */
860 uma_zfree(zone_pack, mref);
863 uma_zfree(zone_clust, m->m_ext.ext_buf);
864 uma_zfree(zone_mbuf, mref);
867 uma_zfree(zone_jumbop, m->m_ext.ext_buf);
868 uma_zfree(zone_mbuf, mref);
871 uma_zfree(zone_jumbo9, m->m_ext.ext_buf);
872 uma_zfree(zone_mbuf, mref);
875 uma_zfree(zone_jumbo16, m->m_ext.ext_buf);
876 uma_zfree(zone_mbuf, mref);
882 KASSERT(mref->m_ext.ext_free != NULL,
883 ("%s: ext_free not set", __func__));
884 mref->m_ext.ext_free(mref);
885 uma_zfree(zone_mbuf, mref);
888 KASSERT(m->m_ext.ext_free != NULL,
889 ("%s: ext_free not set", __func__));
890 m->m_ext.ext_free(m);
893 KASSERT(m->m_ext.ext_type == 0,
894 ("%s: unknown ext_type", __func__));
898 if (freembuf && m != mref)
899 uma_zfree(zone_mbuf, m);
903 * Official mbuf(9) allocation KPI for stack and drivers:
905 * m_get() - a single mbuf without any attachments, sys/mbuf.h.
906 * m_gethdr() - a single mbuf initialized as M_PKTHDR, sys/mbuf.h.
907 * m_getcl() - an mbuf + 2k cluster, sys/mbuf.h.
908 * m_clget() - attach cluster to already allocated mbuf.
909 * m_cljget() - attach jumbo cluster to already allocated mbuf.
910 * m_get2() - allocate minimum mbuf that would fit size argument.
911 * m_getm2() - allocate a chain of mbufs/clusters.
912 * m_extadd() - attach external cluster to mbuf.
914 * m_free() - free single mbuf with its tags and ext, sys/mbuf.h.
915 * m_freem() - free chain of mbufs.
919 m_clget(struct mbuf *m, int how)
922 KASSERT((m->m_flags & M_EXT) == 0, ("%s: mbuf %p has M_EXT",
924 m->m_ext.ext_buf = (char *)NULL;
925 uma_zalloc_arg(zone_clust, m, how);
927 * On a cluster allocation failure, drain the packet zone and retry,
928 * we might be able to loosen a few clusters up on the drain.
930 if ((how & M_NOWAIT) && (m->m_ext.ext_buf == NULL)) {
931 zone_drain(zone_pack);
932 uma_zalloc_arg(zone_clust, m, how);
934 MBUF_PROBE2(m__clget, m, how);
935 return (m->m_flags & M_EXT);
939 * m_cljget() is different from m_clget() as it can allocate clusters without
940 * attaching them to an mbuf. In that case the return value is the pointer
941 * to the cluster of the requested size. If an mbuf was specified, it gets
942 * the cluster attached to it and the return value can be safely ignored.
943 * For size it takes MCLBYTES, MJUMPAGESIZE, MJUM9BYTES, MJUM16BYTES.
946 m_cljget(struct mbuf *m, int how, int size)
952 KASSERT((m->m_flags & M_EXT) == 0, ("%s: mbuf %p has M_EXT",
954 m->m_ext.ext_buf = NULL;
957 zone = m_getzone(size);
958 retval = uma_zalloc_arg(zone, m, how);
960 MBUF_PROBE4(m__cljget, m, how, size, retval);
966 * m_get2() allocates minimum mbuf that would fit "size" argument.
969 m_get2(int size, int how, short type, int flags)
977 if (size <= MHLEN || (size <= MLEN && (flags & M_PKTHDR) == 0))
978 return (uma_zalloc_arg(zone_mbuf, &args, how));
979 if (size <= MCLBYTES)
980 return (uma_zalloc_arg(zone_pack, &args, how));
982 if (size > MJUMPAGESIZE)
985 m = uma_zalloc_arg(zone_mbuf, &args, how);
989 n = uma_zalloc_arg(zone_jumbop, m, how);
991 uma_zfree(zone_mbuf, m);
999 * m_getjcl() returns an mbuf with a cluster of the specified size attached.
1000 * For size it takes MCLBYTES, MJUMPAGESIZE, MJUM9BYTES, MJUM16BYTES.
1003 m_getjcl(int how, short type, int flags, int size)
1005 struct mb_args args;
1009 if (size == MCLBYTES)
1010 return m_getcl(how, type, flags);
1015 m = uma_zalloc_arg(zone_mbuf, &args, how);
1019 zone = m_getzone(size);
1020 n = uma_zalloc_arg(zone, m, how);
1022 uma_zfree(zone_mbuf, m);
1029 * Allocate a given length worth of mbufs and/or clusters (whatever fits
1030 * best) and return a pointer to the top of the allocated chain. If an
1031 * existing mbuf chain is provided, then we will append the new chain
1032 * to the existing one but still return the top of the newly allocated
1036 m_getm2(struct mbuf *m, int len, int how, short type, int flags)
1038 struct mbuf *mb, *nm = NULL, *mtail = NULL;
1040 KASSERT(len >= 0, ("%s: len is < 0", __func__));
1042 /* Validate flags. */
1043 flags &= (M_PKTHDR | M_EOR);
1045 /* Packet header mbuf must be first in chain. */
1046 if ((flags & M_PKTHDR) && m != NULL)
1049 /* Loop and append maximum sized mbufs to the chain tail. */
1052 mb = m_getjcl(how, type, (flags & M_PKTHDR),
1054 else if (len >= MINCLSIZE)
1055 mb = m_getcl(how, type, (flags & M_PKTHDR));
1056 else if (flags & M_PKTHDR)
1057 mb = m_gethdr(how, type);
1059 mb = m_get(how, type);
1061 /* Fail the whole operation if one mbuf can't be allocated. */
1075 flags &= ~M_PKTHDR; /* Only valid on the first mbuf. */
1078 mtail->m_flags |= M_EOR; /* Only valid on the last mbuf. */
1080 /* If mbuf was supplied, append new chain to the end of it. */
1082 for (mtail = m; mtail->m_next != NULL; mtail = mtail->m_next)
1085 mtail->m_flags &= ~M_EOR;
1093 * Configure a provided mbuf to refer to the provided external storage
1094 * buffer and setup a reference count for said buffer.
1097 * mb The existing mbuf to which to attach the provided buffer.
1098 * buf The address of the provided external storage buffer.
1099 * size The size of the provided buffer.
1100 * freef A pointer to a routine that is responsible for freeing the
1101 * provided external storage buffer.
1102 * args A pointer to an argument structure (of any type) to be passed
1103 * to the provided freef routine (may be NULL).
1104 * flags Any other flags to be passed to the provided mbuf.
1105 * type The type that the external storage buffer should be
1112 m_extadd(struct mbuf *mb, char *buf, u_int size, m_ext_free_t freef,
1113 void *arg1, void *arg2, int flags, int type)
1116 KASSERT(type != EXT_CLUSTER, ("%s: EXT_CLUSTER not allowed", __func__));
1118 mb->m_flags |= (M_EXT | flags);
1119 mb->m_ext.ext_buf = buf;
1120 mb->m_data = mb->m_ext.ext_buf;
1121 mb->m_ext.ext_size = size;
1122 mb->m_ext.ext_free = freef;
1123 mb->m_ext.ext_arg1 = arg1;
1124 mb->m_ext.ext_arg2 = arg2;
1125 mb->m_ext.ext_type = type;
1127 if (type != EXT_EXTREF) {
1128 mb->m_ext.ext_count = 1;
1129 mb->m_ext.ext_flags = EXT_FLAG_EMBREF;
1131 mb->m_ext.ext_flags = 0;
1135 * Free an entire chain of mbufs and associated external buffers, if
1139 m_freem(struct mbuf *mb)
1142 MBUF_PROBE1(m__freem, mb);