2 * Copyright (c) 2003, 2004 Matthew Dillon. All rights reserved.
3 * Copyright (c) 2003, 2004 Jeffrey M. Hsu. All rights reserved.
4 * Copyright (c) 2003 Jonathan Lemon. All rights reserved.
5 * Copyright (c) 2003, 2004 The DragonFly Project. All rights reserved.
7 * This code is derived from software contributed to The DragonFly Project
8 * by Jonathan Lemon, Jeffrey M. Hsu, and Matthew Dillon.
10 * Jonathan Lemon gave Jeffrey Hsu permission to combine his copyright
11 * into this one around July 8 2004.
13 * Redistribution and use in source and binary forms, with or without
14 * modification, are permitted provided that the following conditions
16 * 1. Redistributions of source code must retain the above copyright
17 * notice, this list of conditions and the following disclaimer.
18 * 2. Redistributions in binary form must reproduce the above copyright
19 * notice, this list of conditions and the following disclaimer in the
20 * documentation and/or other materials provided with the distribution.
21 * 3. Neither the name of The DragonFly Project nor the names of its
22 * contributors may be used to endorse or promote products derived
23 * from this software without specific, prior written permission.
25 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
26 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
27 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
28 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
29 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
30 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
31 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
32 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
33 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
34 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
35 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
38 * $DragonFly: src/sys/net/netisr.c,v 1.49 2008/11/01 10:29:31 sephe Exp $
41 #include <sys/param.h>
42 #include <sys/systm.h>
43 #include <sys/kernel.h>
44 #include <sys/malloc.h>
45 #include <sys/msgport.h>
47 #include <sys/interrupt.h>
48 #include <sys/socket.h>
49 #include <sys/sysctl.h>
50 #include <sys/socketvar.h>
52 #include <net/if_var.h>
53 #include <net/netisr.h>
54 #include <machine/cpufunc.h>
56 #include <sys/thread2.h>
57 #include <sys/msgport2.h>
58 #include <net/netmsg2.h>
59 #include <sys/mplock2.h>
61 static void netmsg_sync_func(netmsg_t msg);
62 static void netmsg_service_loop(void *arg);
63 static void cpu0_cpufn(struct mbuf **mp, int hoff);
65 struct netmsg_port_registration {
66 TAILQ_ENTRY(netmsg_port_registration) npr_entry;
70 struct netmsg_rollup {
71 TAILQ_ENTRY(netmsg_rollup) ru_entry;
75 static struct netisr netisrs[NETISR_MAX];
76 static TAILQ_HEAD(,netmsg_port_registration) netreglist;
77 static TAILQ_HEAD(,netmsg_rollup) netrulist;
79 /* Per-CPU thread to handle any protocol. */
80 static struct thread netisr_cpu[MAXCPU];
81 lwkt_port netisr_afree_rport;
82 lwkt_port netisr_afree_free_so_rport;
83 lwkt_port netisr_adone_rport;
84 lwkt_port netisr_apanic_rport;
85 lwkt_port netisr_sync_port;
87 static int (*netmsg_fwd_port_fn)(lwkt_port_t, lwkt_msg_t);
89 SYSCTL_NODE(_net, OID_AUTO, netisr, CTLFLAG_RW, 0, "netisr");
92 * netisr_afree_rport replymsg function, only used to handle async
93 * messages which the sender has abandoned to their fate.
96 netisr_autofree_reply(lwkt_port_t port, lwkt_msg_t msg)
98 kfree(msg, M_LWKTMSG);
102 netisr_autofree_free_so_reply(lwkt_port_t port, lwkt_msg_t msg)
104 sofree(((netmsg_t)msg)->base.nm_so);
105 kfree(msg, M_LWKTMSG);
109 * We need a custom putport function to handle the case where the
110 * message target is the current thread's message port. This case
111 * can occur when the TCP or UDP stack does a direct callback to NFS and NFS
112 * then turns around and executes a network operation synchronously.
114 * To prevent deadlocking, we must execute these self-referential messages
115 * synchronously, effectively turning the message into a glorified direct
116 * procedure call back into the protocol stack. The operation must be
117 * complete on return or we will deadlock, so panic if it isn't.
119 * However, the target function is under no obligation to immediately
120 * reply the message. It may forward it elsewhere.
123 netmsg_put_port(lwkt_port_t port, lwkt_msg_t lmsg)
125 netmsg_base_t nmsg = (void *)lmsg;
127 if ((lmsg->ms_flags & MSGF_SYNC) && port == &curthread->td_msgport) {
128 nmsg->nm_dispatch((netmsg_t)nmsg);
131 return(netmsg_fwd_port_fn(port, lmsg));
136 * UNIX DOMAIN sockets still have to run their uipc functions synchronously,
137 * because they depend on the user proc context for a number of things
138 * (like creds) which we have not yet incorporated into the message structure.
140 * However, we maintain or message/port abstraction. Having a special
141 * synchronous port which runs the commands synchronously gives us the
142 * ability to serialize operations in one place later on when we start
146 netmsg_sync_putport(lwkt_port_t port, lwkt_msg_t lmsg)
148 netmsg_base_t nmsg = (void *)lmsg;
150 KKASSERT((lmsg->ms_flags & MSGF_DONE) == 0);
152 lmsg->ms_target_port = port; /* required for abort */
153 nmsg->nm_dispatch((netmsg_t)nmsg);
162 TAILQ_INIT(&netreglist);
163 TAILQ_INIT(&netrulist);
166 * Create default per-cpu threads for generic protocol handling.
168 for (i = 0; i < ncpus; ++i) {
169 lwkt_create(netmsg_service_loop, NULL, NULL,
170 &netisr_cpu[i], TDF_STOPREQ, i,
172 netmsg_service_port_init(&netisr_cpu[i].td_msgport);
173 lwkt_schedule(&netisr_cpu[i]);
177 * The netisr_afree_rport is a special reply port which automatically
178 * frees the replied message. The netisr_adone_rport simply marks
179 * the message as being done. The netisr_apanic_rport panics if
180 * the message is replied to.
182 lwkt_initport_replyonly(&netisr_afree_rport, netisr_autofree_reply);
183 lwkt_initport_replyonly(&netisr_afree_free_so_rport,
184 netisr_autofree_free_so_reply);
185 lwkt_initport_replyonly_null(&netisr_adone_rport);
186 lwkt_initport_panic(&netisr_apanic_rport);
189 * The netisr_syncport is a special port which executes the message
190 * synchronously and waits for it if EASYNC is returned.
192 lwkt_initport_putonly(&netisr_sync_port, netmsg_sync_putport);
195 SYSINIT(netisr, SI_SUB_PRE_DRIVERS, SI_ORDER_FIRST, netisr_init, NULL);
198 * Finish initializing the message port for a netmsg service. This also
199 * registers the port for synchronous cleanup operations such as when an
200 * ifnet is being destroyed. There is no deregistration API yet.
203 netmsg_service_port_init(lwkt_port_t port)
205 struct netmsg_port_registration *reg;
208 * Override the putport function. Our custom function checks for
209 * self-references and executes such commands synchronously.
211 if (netmsg_fwd_port_fn == NULL)
212 netmsg_fwd_port_fn = port->mp_putport;
213 KKASSERT(netmsg_fwd_port_fn == port->mp_putport);
214 port->mp_putport = netmsg_put_port;
217 * Keep track of ports using the netmsg API so we can synchronize
218 * certain operations (such as freeing an ifnet structure) across all
221 reg = kmalloc(sizeof(*reg), M_TEMP, M_WAITOK|M_ZERO);
222 reg->npr_port = port;
223 TAILQ_INSERT_TAIL(&netreglist, reg, npr_entry);
227 * This function synchronizes the caller with all netmsg services. For
228 * example, if an interface is being removed we must make sure that all
229 * packets related to that interface complete processing before the structure
230 * can actually be freed. This sort of synchronization is an alternative to
231 * ref-counting the netif, removing the ref counting overhead in favor of
232 * placing additional overhead in the netif freeing sequence (where it is
236 netmsg_service_sync(void)
238 struct netmsg_port_registration *reg;
239 struct netmsg_base smsg;
241 netmsg_init(&smsg, NULL, &curthread->td_msgport, 0, netmsg_sync_func);
243 TAILQ_FOREACH(reg, &netreglist, npr_entry) {
244 lwkt_domsg(reg->npr_port, &smsg.lmsg, 0);
249 * The netmsg function simply replies the message. API semantics require
250 * EASYNC to be returned if the netmsg function disposes of the message.
253 netmsg_sync_func(netmsg_t msg)
255 lwkt_replymsg(&msg->lmsg, 0);
259 * Generic netmsg service loop. Some protocols may roll their own but all
260 * must do the basic command dispatch function call done here.
263 netmsg_service_loop(void *arg)
265 struct netmsg_rollup *ru;
267 thread_t td = curthread;;
270 while ((msg = lwkt_waitport(&td->td_msgport, 0))) {
272 * Run up to 512 pending netmsgs.
276 KASSERT(msg->nm_dispatch != NULL,
277 ("netmsg_service isr %d badmsg\n",
278 msg->lmsg.u.ms_result));
280 msg->nm_so->so_port != &td->td_msgport) {
282 * Sockets undergoing connect or disconnect
283 * ops can change ports on us. Chase the
286 kprintf("netmsg_service_loop: Warning, "
287 "port changed so=%p\n", msg->nm_so);
288 lwkt_forwardmsg(msg->nm_so->so_port,
292 * We are on the correct port, dispatch it.
294 msg->nm_dispatch((netmsg_t)msg);
298 } while ((msg = lwkt_getport(&td->td_msgport)) != NULL);
301 * Run all registered rollup functions for this cpu
302 * (e.g. tcp_willblock()).
304 TAILQ_FOREACH(ru, &netrulist, ru_entry)
310 * Forward a packet to a netisr service function.
312 * If the packet has not been assigned to a protocol thread we call
313 * the port characterization function to assign it. The caller must
314 * clear M_HASH (or not have set it in the first place) if the caller
315 * wishes the packet to be recharacterized.
318 netisr_queue(int num, struct mbuf *m)
321 struct netmsg_packet *pmsg;
324 KASSERT((num > 0 && num <= (sizeof(netisrs)/sizeof(netisrs[0]))),
325 ("Bad isr %d", num));
328 if (ni->ni_handler == NULL) {
329 kprintf("Unregistered isr %d\n", num);
335 * Figure out which protocol thread to send to. This does not
336 * have to be perfect but performance will be really good if it
337 * is correct. Major protocol inputs such as ip_input() will
338 * re-characterize the packet as necessary.
340 if ((m->m_flags & M_HASH) == 0) {
346 if ((m->m_flags & M_HASH) == 0) {
347 kprintf("netisr_queue(%d): packet hash failed\n", num);
354 * Get the protocol port based on the packet hash, initialize
355 * the netmsg, and send it off.
357 port = cpu_portfn(m->m_pkthdr.hash);
358 pmsg = &m->m_hdr.mh_netmsg;
359 netmsg_init(&pmsg->base, NULL, &netisr_apanic_rport,
362 pmsg->base.lmsg.u.ms_result = num;
363 lwkt_sendmsg(port, &pmsg->base.lmsg);
369 * Pre-characterization of a deeper portion of the packet for the
372 * The base of the ISR type (e.g. IP) that we want to characterize is
373 * at (hoff) relative to the beginning of the mbuf. This allows
374 * e.g. ether_input_chain() to not have to adjust the m_data/m_len.
377 netisr_characterize(int num, struct mbuf **mp, int hoff)
388 if (num < 0 || num >= NETISR_MAX) {
389 if (num == NETISR_MAX) {
390 m->m_flags |= M_HASH;
391 m->m_pkthdr.hash = 0;
394 panic("Bad isr %d", num);
401 if (ni->ni_handler == NULL) {
402 kprintf("Unregistered isr %d\n", num);
408 * Characterize the packet
410 if ((m->m_flags & M_HASH) == 0) {
411 ni->ni_cpufn(mp, hoff);
413 if (m && (m->m_flags & M_HASH) == 0)
414 kprintf("netisr_queue(%d): packet hash failed\n", num);
419 netisr_register(int num, netisr_fn_t handler, netisr_cpufn_t cpufn)
423 KASSERT((num > 0 && num <= (sizeof(netisrs)/sizeof(netisrs[0]))),
424 ("netisr_register: bad isr %d", num));
425 KKASSERT(handler != NULL);
432 ni->ni_handler = handler;
433 ni->ni_cpufn = cpufn;
434 netmsg_init(&ni->ni_netmsg, NULL, &netisr_adone_rport, 0, NULL);
438 netisr_register_rollup(netisr_ru_t ru_func)
440 struct netmsg_rollup *ru;
442 ru = kmalloc(sizeof(*ru), M_TEMP, M_WAITOK|M_ZERO);
443 ru->ru_func = ru_func;
444 TAILQ_INSERT_TAIL(&netrulist, ru, ru_entry);
448 * Return the message port for the general protocol message servicing
449 * thread for a particular cpu.
454 KKASSERT(cpu >= 0 && cpu < ncpus);
455 return (&netisr_cpu[cpu].td_msgport);
459 * Return the current cpu's network protocol thread.
464 return(cpu_portfn(mycpu->gd_cpuid));
468 * Return a default protocol control message processing thread port
471 cpu0_ctlport(int cmd __unused, struct sockaddr *sa __unused,
472 void *extra __unused)
474 return (&netisr_cpu[0].td_msgport);
478 * This is a default netisr packet characterization function which
479 * sets M_HASH. If a netisr is registered with a NULL cpufn function
480 * this one is assigned.
482 * This function makes no attempt to validate the packet.
485 cpu0_cpufn(struct mbuf **mp, int hoff __unused)
487 struct mbuf *m = *mp;
489 m->m_flags |= M_HASH;
490 m->m_pkthdr.hash = 0;
494 * schednetisr() is used to call the netisr handler from the appropriate
495 * netisr thread for polling and other purposes.
497 * This function may be called from a hard interrupt or IPI and must be
498 * MP SAFE and non-blocking. We use a fixed per-cpu message instead of
499 * trying to allocate one. We must get ourselves onto the target cpu
500 * to safely check the MSGF_DONE bit on the message but since the message
501 * will be sent to that cpu anyway this does not add any extra work beyond
502 * what lwkt_sendmsg() would have already had to do to schedule the target
506 schednetisr_remote(void *data)
508 int num = (int)(intptr_t)data;
509 struct netisr *ni = &netisrs[num];
510 lwkt_port_t port = &netisr_cpu[0].td_msgport;
513 pmsg = &netisrs[num].ni_netmsg;
514 if (pmsg->lmsg.ms_flags & MSGF_DONE) {
515 netmsg_init(pmsg, NULL, &netisr_adone_rport, 0, ni->ni_handler);
516 pmsg->lmsg.u.ms_result = num;
517 lwkt_sendmsg(port, &pmsg->lmsg);
524 KASSERT((num > 0 && num <= (sizeof(netisrs)/sizeof(netisrs[0]))),
525 ("schednetisr: bad isr %d", num));
526 KKASSERT(netisrs[num].ni_handler != NULL);
528 if (mycpu->gd_cpuid != 0) {
529 lwkt_send_ipiq(globaldata_find(0),
530 schednetisr_remote, (void *)(intptr_t)num);
533 schednetisr_remote((void *)(intptr_t)num);
538 schednetisr_remote((void *)(intptr_t)num);