/*- * Copyright (c) 2004 * Bosko Milekic . * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice unmodified, this list of conditions and the following * disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the author nor the names of contributors may be * used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include __FBSDID("$FreeBSD: head/sys/kern/kern_mbuf.c 129947 2004-06-01 16:17:10Z bmilekic $"); #include "opt_mac.h" #include "opt_param.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* * In FreeBSD, Mbufs and Mbuf Clusters are allocated from UMA * Zones. * * Mbuf Clusters (2K, contiguous) are allocated from the Cluster * Zone. The Zone can be capped at kern.ipc.nmbclusters, if the * administrator so desires. * * Mbufs are allocated from a UMA Master Zone called the Mbuf * Zone. * * Additionally, FreeBSD provides a Packet Zone, which it * configures as a Secondary Zone to the Mbuf Master Zone, * thus sharing backend Slab kegs with the Mbuf Master Zone. * * Thus common-case allocations and locking are simplified: * * m_clget() m_getcl() * | | * | .------------>[(Packet Cache)] m_get(), m_gethdr() * | | [ Packet ] | * [(Cluster Cache)] [ Secondary ] [ (Mbuf Cache) ] * [ Cluster Zone ] [ Zone ] [ Mbuf Master Zone ] * | \________ | * [ Cluster Keg ] \ / * | [ Mbuf Keg ] * [ Cluster Slabs ] | * | [ Mbuf Slabs ] * \____________(VM)_________________/ */ int nmbclusters; struct mbstat mbstat; static void tunable_mbinit(void *dummy) { /* This has to be done before VM init. */ nmbclusters = 1024 + maxusers * 64; TUNABLE_INT_FETCH("kern.ipc.nmbclusters", &nmbclusters); } SYSINIT(tunable_mbinit, SI_SUB_TUNABLES, SI_ORDER_ANY, tunable_mbinit, NULL); SYSCTL_DECL(_kern_ipc); SYSCTL_INT(_kern_ipc, OID_AUTO, nmbclusters, CTLFLAG_RW, &nmbclusters, 0, "Maximum number of mbuf clusters allowed"); SYSCTL_STRUCT(_kern_ipc, OID_AUTO, mbstat, CTLFLAG_RD, &mbstat, mbstat, "Mbuf general information and statistics"); /* * Zones from which we allocate. */ uma_zone_t zone_mbuf; uma_zone_t zone_clust; uma_zone_t zone_pack; /* * Local prototypes. */ static void mb_ctor_mbuf(void *, int, void *); static void mb_ctor_clust(void *, int, void *); static void mb_ctor_pack(void *, int, void *); static void mb_dtor_mbuf(void *, int, void *); static void mb_dtor_clust(void *, int, void *); /* XXX */ static void mb_dtor_pack(void *, int, void *); /* XXX */ static void mb_init_pack(void *, int); static void mb_fini_pack(void *, int); static void mb_reclaim(void *); static void mbuf_init(void *); /* * Initialize FreeBSD Network buffer allocation. */ SYSINIT(mbuf, SI_SUB_MBUF, SI_ORDER_FIRST, mbuf_init, NULL) static void mbuf_init(void *dummy) { /* * Configure UMA zones for Mbufs, Clusters, and Packets. */ zone_mbuf = uma_zcreate("Mbuf", MSIZE, mb_ctor_mbuf, mb_dtor_mbuf, NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_MAXBUCKET); zone_clust = uma_zcreate("MbufClust", MCLBYTES, mb_ctor_clust, mb_dtor_clust, NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_REFCNT); if (nmbclusters > 0) uma_zone_set_max(zone_clust, nmbclusters); zone_pack = uma_zsecond_create("Packet", mb_ctor_pack, mb_dtor_pack, mb_init_pack, mb_fini_pack, zone_mbuf); /* uma_prealloc() goes here */ /* * Hook event handler for low-memory situation, used to * drain protocols and push data back to the caches (UMA * later pushes it back to VM). */ EVENTHANDLER_REGISTER(vm_lowmem, mb_reclaim, NULL, EVENTHANDLER_PRI_FIRST); /* * [Re]set counters and local statistics knobs. * XXX Some of these should go and be replaced, but UMA stat * gathering needs to be revised. */ mbstat.m_mbufs = 0; mbstat.m_mclusts = 0; mbstat.m_drain = 0; mbstat.m_msize = MSIZE; mbstat.m_mclbytes = MCLBYTES; mbstat.m_minclsize = MINCLSIZE; mbstat.m_mlen = MLEN; mbstat.m_mhlen = MHLEN; mbstat.m_numtypes = MT_NTYPES; mbstat.m_mcfail = mbstat.m_mpfail = 0; mbstat.sf_iocnt = 0; mbstat.sf_allocwait = mbstat.sf_allocfail = 0; } /* * Constructor for Mbuf master zone. * * The 'arg' pointer points to a mb_args structure which * contains call-specific information required to support the * mbuf allocation API. */ static void mb_ctor_mbuf(void *mem, int size, void *arg) { struct mbuf *m; struct mb_args *args; int flags; int how; short type; m = (struct mbuf *)mem; args = (struct mb_args *)arg; flags = args->flags; how = args->how; type = args->type; m->m_type = type; m->m_next = NULL; m->m_nextpkt = NULL; m->m_flags = flags; if (flags & M_PKTHDR) { m->m_data = m->m_pktdat; m->m_pkthdr.rcvif = NULL; m->m_pkthdr.csum_flags = 0; SLIST_INIT(&m->m_pkthdr.tags); #ifdef MAC /* If the label init fails, fail the alloc */ if (mac_init_mbuf(m, how) != 0) { m_free(m); /* XXX*/ panic("mb_ctor_mbuf(): can't deal with failure!"); /* return 0; */ } #endif } else m->m_data = m->m_dat; mbstat.m_mbufs += 1; /* XXX */ /* return 1; */ } /* * The Mbuf master zone and Packet secondary zone destructor. */ static void mb_dtor_mbuf(void *mem, int size, void *arg) { struct mbuf *m; m = (struct mbuf *)mem; if ((m->m_flags & M_PKTHDR) != 0) m_tag_delete_chain(m, NULL); mbstat.m_mbufs -= 1; /* XXX */ } /* XXX Only because of stats */ static void mb_dtor_pack(void *mem, int size, void *arg) { struct mbuf *m; m = (struct mbuf *)mem; if ((m->m_flags & M_PKTHDR) != 0) m_tag_delete_chain(m, NULL); mbstat.m_mbufs -= 1; /* XXX */ mbstat.m_mclusts -= 1; /* XXX */ } /* * The Cluster zone constructor. * * Here the 'arg' pointer points to the Mbuf which we * are configuring cluster storage for. */ static void mb_ctor_clust(void *mem, int size, void *arg) { struct mbuf *m; m = (struct mbuf *)arg; m->m_ext.ext_buf = (caddr_t)mem; m->m_data = m->m_ext.ext_buf; m->m_flags |= M_EXT; m->m_ext.ext_free = NULL; m->m_ext.ext_args = NULL; m->m_ext.ext_size = MCLBYTES; m->m_ext.ext_type = EXT_CLUSTER; m->m_ext.ref_cnt = (u_int *)uma_find_refcnt(zone_clust, m->m_ext.ext_buf); *(m->m_ext.ref_cnt) = 1; mbstat.m_mclusts += 1; /* XXX */ /* return 1; */ } /* XXX */ static void mb_dtor_clust(void *mem, int size, void *arg) { mbstat.m_mclusts -= 1; /* XXX */ } /* * The Packet secondary zone's init routine, executed on the * object's transition from keg slab to zone cache. */ static void mb_init_pack(void *mem, int size) { struct mbuf *m; m = (struct mbuf *)mem; m->m_ext.ext_buf = NULL; uma_zalloc_arg(zone_clust, m, M_NOWAIT); if (m->m_ext.ext_buf == NULL) /* XXX */ panic("mb_init_pack(): Can't deal with failure yet."); mbstat.m_mclusts -= 1; /* XXX */ } /* * The Packet secondary zone's fini routine, executed on the * object's transition from zone cache to keg slab. */ static void mb_fini_pack(void *mem, int size) { struct mbuf *m; m = (struct mbuf *)mem; uma_zfree_arg(zone_clust, m->m_ext.ext_buf, NULL); m->m_ext.ext_buf = NULL; mbstat.m_mclusts += 1; /* XXX */ } /* * The "packet" keg constructor. */ static void mb_ctor_pack(void *mem, int size, void *arg) { struct mbuf *m; struct mb_args *args; int flags, how; short type; m = (struct mbuf *)mem; args = (struct mb_args *)arg; flags = args->flags; type = args->type; how = args->how; m->m_type = type; m->m_next = NULL; m->m_nextpkt = NULL; m->m_data = m->m_ext.ext_buf; m->m_flags = flags|M_EXT; m->m_ext.ext_free = NULL; m->m_ext.ext_args = NULL; m->m_ext.ext_size = MCLBYTES; m->m_ext.ext_type = EXT_PACKET; *(m->m_ext.ref_cnt) = 1; if (flags & M_PKTHDR) { m->m_pkthdr.rcvif = NULL; m->m_pkthdr.csum_flags = 0; SLIST_INIT(&m->m_pkthdr.tags); #ifdef MAC /* If the label init fails, fail the alloc */ if (mac_init_mbuf(m, how) != 0) { m_free(m); /* XXX*/ panic("mb_ctor_pack(): can't deal with failure!"); /* return 0; */ } #endif } mbstat.m_mbufs += 1; /* XXX */ mbstat.m_mclusts += 1; /* XXX */ /* return 1; */ } /* * This is the protocol drain routine. * * No locks should be held when this is called. The drain routines have to * presently acquire some locks which raises the possibility of lock order * reversal. */ static void mb_reclaim(void *junk) { struct domain *dp; struct protosw *pr; WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK | WARN_PANIC, NULL, "mb_reclaim()"); mbstat.m_drain++; for (dp = domains; dp != NULL; dp = dp->dom_next) for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++) if (pr->pr_drain != NULL) (*pr->pr_drain)(); }