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 1.40 2008/05/02 07:40:32 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>
51 #include <net/if_var.h>
52 #include <net/netisr.h>
53 #include <machine/cpufunc.h>
55 #include <sys/thread2.h>
56 #include <sys/msgport2.h>
57 #include <net/netmsg2.h>
59 static void netmsg_sync_func(struct netmsg *msg);
61 struct netmsg_port_registration {
62 TAILQ_ENTRY(netmsg_port_registration) npr_entry;
66 static struct netisr netisrs[NETISR_MAX];
67 static TAILQ_HEAD(,netmsg_port_registration) netreglist;
69 /* Per-CPU thread to handle any protocol. */
70 struct thread netisr_cpu[MAXCPU];
71 lwkt_port netisr_afree_rport;
72 lwkt_port netisr_adone_rport;
73 lwkt_port netisr_apanic_rport;
74 lwkt_port netisr_sync_port;
76 static int (*netmsg_fwd_port_fn)(lwkt_port_t, lwkt_msg_t);
78 static int netisr_mpsafe_thread = 0;
79 TUNABLE_INT("netisr.mpsafe_thread", &netisr_mpsafe_thread);
82 * netisr_afree_rport replymsg function, only used to handle async
83 * messages which the sender has abandoned to their fate.
86 netisr_autofree_reply(lwkt_port_t port, lwkt_msg_t msg)
88 kfree(msg, M_LWKTMSG);
92 * We need a custom putport function to handle the case where the
93 * message target is the current thread's message port. This case
94 * can occur when the TCP or UDP stack does a direct callback to NFS and NFS
95 * then turns around and executes a network operation synchronously.
97 * To prevent deadlocking, we must execute these self-referential messages
98 * synchronously, effectively turning the message into a glorified direct
99 * procedure call back into the protocol stack. The operation must be
100 * complete on return or we will deadlock, so panic if it isn't.
103 netmsg_put_port(lwkt_port_t port, lwkt_msg_t lmsg)
105 netmsg_t netmsg = (void *)lmsg;
107 if ((lmsg->ms_flags & MSGF_SYNC) && port == &curthread->td_msgport) {
108 netmsg->nm_dispatch(netmsg);
109 if ((lmsg->ms_flags & MSGF_DONE) == 0)
110 panic("netmsg_put_port: self-referential deadlock on netport");
113 return(netmsg_fwd_port_fn(port, lmsg));
118 * UNIX DOMAIN sockets still have to run their uipc functions synchronously,
119 * because they depend on the user proc context for a number of things
120 * (like creds) which we have not yet incorporated into the message structure.
122 * However, we maintain or message/port abstraction. Having a special
123 * synchronous port which runs the commands synchronously gives us the
124 * ability to serialize operations in one place later on when we start
128 netmsg_sync_putport(lwkt_port_t port, lwkt_msg_t lmsg)
130 netmsg_t netmsg = (void *)lmsg;
132 KKASSERT((lmsg->ms_flags & MSGF_DONE) == 0);
134 lmsg->ms_target_port = port; /* required for abort */
135 netmsg->nm_dispatch(netmsg);
144 TAILQ_INIT(&netreglist);
147 * Create default per-cpu threads for generic protocol handling.
149 for (i = 0; i < ncpus; ++i) {
150 lwkt_create(netisr_mpsafe_thread ?
151 netmsg_service_loop_mpsafe : netmsg_service_loop,
152 NULL, NULL, &netisr_cpu[i],
153 0, i, "netisr_cpu %d", i);
154 netmsg_service_port_init(&netisr_cpu[i].td_msgport);
158 * The netisr_afree_rport is a special reply port which automatically
159 * frees the replied message. The netisr_adone_rport simply marks
160 * the message as being done. The netisr_apanic_rport panics if
161 * the message is replied to.
163 lwkt_initport_replyonly(&netisr_afree_rport, netisr_autofree_reply);
164 lwkt_initport_replyonly_null(&netisr_adone_rport);
165 lwkt_initport_panic(&netisr_apanic_rport);
168 * The netisr_syncport is a special port which executes the message
169 * synchronously and waits for it if EASYNC is returned.
171 lwkt_initport_putonly(&netisr_sync_port, netmsg_sync_putport);
174 SYSINIT(netisr, SI_SUB_PRE_DRIVERS, SI_ORDER_FIRST, netisr_init, NULL);
177 * Finish initializing the message port for a netmsg service. This also
178 * registers the port for synchronous cleanup operations such as when an
179 * ifnet is being destroyed. There is no deregistration API yet.
182 netmsg_service_port_init(lwkt_port_t port)
184 struct netmsg_port_registration *reg;
187 * Override the putport function. Our custom function checks for
188 * self-references and executes such commands synchronously.
190 if (netmsg_fwd_port_fn == NULL)
191 netmsg_fwd_port_fn = port->mp_putport;
192 KKASSERT(netmsg_fwd_port_fn == port->mp_putport);
193 port->mp_putport = netmsg_put_port;
196 * Keep track of ports using the netmsg API so we can synchronize
197 * certain operations (such as freeing an ifnet structure) across all
200 reg = kmalloc(sizeof(*reg), M_TEMP, M_WAITOK|M_ZERO);
201 reg->npr_port = port;
202 TAILQ_INSERT_TAIL(&netreglist, reg, npr_entry);
206 * This function synchronizes the caller with all netmsg services. For
207 * example, if an interface is being removed we must make sure that all
208 * packets related to that interface complete processing before the structure
209 * can actually be freed. This sort of synchronization is an alternative to
210 * ref-counting the netif, removing the ref counting overhead in favor of
211 * placing additional overhead in the netif freeing sequence (where it is
215 netmsg_service_sync(void)
217 struct netmsg_port_registration *reg;
220 netmsg_init(&smsg, &curthread->td_msgport, 0, netmsg_sync_func);
222 TAILQ_FOREACH(reg, &netreglist, npr_entry) {
223 lwkt_domsg(reg->npr_port, &smsg.nm_lmsg, 0);
228 * The netmsg function simply replies the message. API semantics require
229 * EASYNC to be returned if the netmsg function disposes of the message.
232 netmsg_sync_func(struct netmsg *msg)
234 lwkt_replymsg(&msg->nm_lmsg, 0);
238 * Generic netmsg service loop. Some protocols may roll their own but all
239 * must do the basic command dispatch function call done here.
242 netmsg_service_loop(void *arg)
246 while ((msg = lwkt_waitport(&curthread->td_msgport, 0))) {
247 msg->nm_dispatch(msg);
252 * MPSAFE version of netmsg_service_loop()
255 netmsg_service_loop_mpsafe(void *arg)
261 while ((msg = lwkt_waitport(&curthread->td_msgport, 0))) {
262 msg->nm_dispatch(msg);
267 * Call the netisr directly.
268 * Queueing may be done in the msg port layer at its discretion.
271 netisr_dispatch(int num, struct mbuf *m)
273 /* just queue it for now XXX JH */
274 netisr_queue(num, m);
278 * Same as netisr_dispatch(), but always queue.
279 * This is either used in places where we are not confident that
280 * direct dispatch is possible, or where queueing is required.
283 netisr_queue(int num, struct mbuf *m)
286 struct netmsg_packet *pmsg;
289 KASSERT((num > 0 && num <= (sizeof(netisrs)/sizeof(netisrs[0]))),
290 ("netisr_queue: bad isr %d", num));
293 if (ni->ni_handler == NULL) {
294 kprintf("netisr_queue: unregistered isr %d\n", num);
299 if ((port = ni->ni_mport(&m)) == NULL)
302 pmsg = &m->m_hdr.mh_netmsg;
304 netmsg_init(&pmsg->nm_netmsg, &netisr_apanic_rport, 0, ni->ni_handler);
306 pmsg->nm_netmsg.nm_lmsg.u.ms_result = num;
307 lwkt_sendmsg(port, &pmsg->nm_netmsg.nm_lmsg);
312 netisr_register(int num, lwkt_portfn_t mportfn, netisr_fn_t handler)
314 KASSERT((num > 0 && num <= (sizeof(netisrs)/sizeof(netisrs[0]))),
315 ("netisr_register: bad isr %d", num));
316 netmsg_init(&netisrs[num].ni_netmsg, &netisr_adone_rport, 0, NULL);
317 netisrs[num].ni_mport = mportfn;
318 netisrs[num].ni_handler = handler;
322 netisr_unregister(int num)
324 KASSERT((num > 0 && num <= (sizeof(netisrs)/sizeof(netisrs[0]))),
325 ("unregister_netisr: bad isr number: %d\n", num));
332 * Return message port for default handler thread on CPU 0.
335 cpu0_portfn(struct mbuf **mptr)
337 return (&netisr_cpu[0].td_msgport);
343 return (&netisr_cpu[cpu].td_msgport);
348 cpu0_soport(struct socket *so __unused, struct sockaddr *nam __unused,
349 struct mbuf **dummy __unused, int req __unused)
351 return (&netisr_cpu[0].td_msgport);
355 sync_soport(struct socket *so __unused, struct sockaddr *nam __unused,
356 struct mbuf **dummy __unused, int req __unused)
358 return (&netisr_sync_port);
362 * schednetisr() is used to call the netisr handler from the appropriate
363 * netisr thread for polling and other purposes.
365 * This function may be called from a hard interrupt or IPI and must be
366 * MP SAFE and non-blocking. We use a fixed per-cpu message instead of
367 * trying to allocate one. We must get ourselves onto the target cpu
368 * to safely check the MSGF_DONE bit on the message but since the message
369 * will be sent to that cpu anyway this does not add any extra work beyond
370 * what lwkt_sendmsg() would have already had to do to schedule the target
374 schednetisr_remote(void *data)
377 struct netisr *ni = &netisrs[num];
378 lwkt_port_t port = &netisr_cpu[0].td_msgport;
381 pmsg = &netisrs[num].ni_netmsg;
383 if (pmsg->nm_lmsg.ms_flags & MSGF_DONE) {
384 netmsg_init(pmsg, &netisr_adone_rport, 0, ni->ni_handler);
385 pmsg->nm_lmsg.u.ms_result = num;
386 lwkt_sendmsg(port, &pmsg->nm_lmsg);
394 KASSERT((num > 0 && num <= (sizeof(netisrs)/sizeof(netisrs[0]))),
395 ("schednetisr: bad isr %d", num));
397 if (mycpu->gd_cpuid != 0)
398 lwkt_send_ipiq(globaldata_find(0), schednetisr_remote, (void *)num);
400 schednetisr_remote((void *)num);
402 schednetisr_remote((void *)num);
407 netisr_mport(int num, struct mbuf **m0)
410 struct netmsg_packet *pmsg;
412 struct mbuf *m = *m0;
416 KASSERT((num > 0 && num <= (sizeof(netisrs)/sizeof(netisrs[0]))),
417 ("netisr_queue: bad isr %d", num));
420 if (ni->ni_handler == NULL) {
421 kprintf("netisr_queue: unregistered isr %d\n", num);
426 if ((port = ni->ni_mport(&m)) == NULL)
429 pmsg = &m->m_hdr.mh_netmsg;
431 netmsg_init(&pmsg->nm_netmsg, &netisr_apanic_rport, 0, ni->ni_handler);
433 pmsg->nm_netmsg.nm_lmsg.u.ms_result = num;