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>
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 #define NETISR_GET_MPLOCK(ni) \
61 if (((ni)->ni_flags & NETISR_FLAG_MPSAFE) == 0) \
65 #define NETISR_REL_MPLOCK(ni) \
67 if (((ni)->ni_flags & NETISR_FLAG_MPSAFE) == 0) \
71 static void netmsg_sync_func(struct netmsg
*msg
);
73 struct netmsg_port_registration
{
74 TAILQ_ENTRY(netmsg_port_registration
) npr_entry
;
78 static struct netisr netisrs
[NETISR_MAX
];
79 static TAILQ_HEAD(,netmsg_port_registration
) netreglist
;
81 /* Per-CPU thread to handle any protocol. */
82 struct thread netisr_cpu
[MAXCPU
];
83 lwkt_port netisr_afree_rport
;
84 lwkt_port netisr_adone_rport
;
85 lwkt_port netisr_apanic_rport
;
86 lwkt_port netisr_sync_port
;
88 static int (*netmsg_fwd_port_fn
)(lwkt_port_t
, lwkt_msg_t
);
90 static int netisr_mpsafe_thread
= NETMSG_SERVICE_ADAPTIVE
;
91 TUNABLE_INT("net.netisr.mpsafe_thread", &netisr_mpsafe_thread
);
93 SYSCTL_NODE(_net
, OID_AUTO
, netisr
, CTLFLAG_RW
, 0, "netisr");
94 SYSCTL_INT(_net_netisr
, OID_AUTO
, mpsafe_thread
, CTLFLAG_RW
,
95 &netisr_mpsafe_thread
, 0,
96 "0:BGL, 1:Adaptive BGL, 2:No BGL(experimental)");
99 NETISR_TO_MSGF(const struct netisr
*ni
)
103 if (ni
->ni_flags
& NETISR_FLAG_MPSAFE
)
104 msg_flags
|= MSGF_MPSAFE
;
109 * netisr_afree_rport replymsg function, only used to handle async
110 * messages which the sender has abandoned to their fate.
113 netisr_autofree_reply(lwkt_port_t port
, lwkt_msg_t msg
)
115 kfree(msg
, M_LWKTMSG
);
119 * We need a custom putport function to handle the case where the
120 * message target is the current thread's message port. This case
121 * can occur when the TCP or UDP stack does a direct callback to NFS and NFS
122 * then turns around and executes a network operation synchronously.
124 * To prevent deadlocking, we must execute these self-referential messages
125 * synchronously, effectively turning the message into a glorified direct
126 * procedure call back into the protocol stack. The operation must be
127 * complete on return or we will deadlock, so panic if it isn't.
130 netmsg_put_port(lwkt_port_t port
, lwkt_msg_t lmsg
)
132 netmsg_t netmsg
= (void *)lmsg
;
134 if ((lmsg
->ms_flags
& MSGF_SYNC
) && port
== &curthread
->td_msgport
) {
135 netmsg
->nm_dispatch(netmsg
);
136 if ((lmsg
->ms_flags
& MSGF_DONE
) == 0)
137 panic("netmsg_put_port: self-referential deadlock on netport");
140 return(netmsg_fwd_port_fn(port
, lmsg
));
145 * UNIX DOMAIN sockets still have to run their uipc functions synchronously,
146 * because they depend on the user proc context for a number of things
147 * (like creds) which we have not yet incorporated into the message structure.
149 * However, we maintain or message/port abstraction. Having a special
150 * synchronous port which runs the commands synchronously gives us the
151 * ability to serialize operations in one place later on when we start
155 netmsg_sync_putport(lwkt_port_t port
, lwkt_msg_t lmsg
)
157 netmsg_t netmsg
= (void *)lmsg
;
159 KKASSERT((lmsg
->ms_flags
& MSGF_DONE
) == 0);
161 lmsg
->ms_target_port
= port
; /* required for abort */
162 netmsg
->nm_dispatch(netmsg
);
171 TAILQ_INIT(&netreglist
);
174 * Create default per-cpu threads for generic protocol handling.
176 for (i
= 0; i
< ncpus
; ++i
) {
177 lwkt_create(netmsg_service_loop
, &netisr_mpsafe_thread
, NULL
,
178 &netisr_cpu
[i
], TDF_NETWORK
| TDF_MPSAFE
, i
,
180 netmsg_service_port_init(&netisr_cpu
[i
].td_msgport
);
184 * The netisr_afree_rport is a special reply port which automatically
185 * frees the replied message. The netisr_adone_rport simply marks
186 * the message as being done. The netisr_apanic_rport panics if
187 * the message is replied to.
189 lwkt_initport_replyonly(&netisr_afree_rport
, netisr_autofree_reply
);
190 lwkt_initport_replyonly_null(&netisr_adone_rport
);
191 lwkt_initport_panic(&netisr_apanic_rport
);
194 * The netisr_syncport is a special port which executes the message
195 * synchronously and waits for it if EASYNC is returned.
197 lwkt_initport_putonly(&netisr_sync_port
, netmsg_sync_putport
);
200 SYSINIT(netisr
, SI_SUB_PRE_DRIVERS
, SI_ORDER_FIRST
, netisr_init
, NULL
);
203 * Finish initializing the message port for a netmsg service. This also
204 * registers the port for synchronous cleanup operations such as when an
205 * ifnet is being destroyed. There is no deregistration API yet.
208 netmsg_service_port_init(lwkt_port_t port
)
210 struct netmsg_port_registration
*reg
;
213 * Override the putport function. Our custom function checks for
214 * self-references and executes such commands synchronously.
216 if (netmsg_fwd_port_fn
== NULL
)
217 netmsg_fwd_port_fn
= port
->mp_putport
;
218 KKASSERT(netmsg_fwd_port_fn
== port
->mp_putport
);
219 port
->mp_putport
= netmsg_put_port
;
222 * Keep track of ports using the netmsg API so we can synchronize
223 * certain operations (such as freeing an ifnet structure) across all
226 reg
= kmalloc(sizeof(*reg
), M_TEMP
, M_WAITOK
|M_ZERO
);
227 reg
->npr_port
= port
;
228 TAILQ_INSERT_TAIL(&netreglist
, reg
, npr_entry
);
232 * This function synchronizes the caller with all netmsg services. For
233 * example, if an interface is being removed we must make sure that all
234 * packets related to that interface complete processing before the structure
235 * can actually be freed. This sort of synchronization is an alternative to
236 * ref-counting the netif, removing the ref counting overhead in favor of
237 * placing additional overhead in the netif freeing sequence (where it is
241 netmsg_service_sync(void)
243 struct netmsg_port_registration
*reg
;
246 netmsg_init(&smsg
, &curthread
->td_msgport
, MSGF_MPSAFE
, netmsg_sync_func
);
248 TAILQ_FOREACH(reg
, &netreglist
, npr_entry
) {
249 lwkt_domsg(reg
->npr_port
, &smsg
.nm_lmsg
, 0);
254 * The netmsg function simply replies the message. API semantics require
255 * EASYNC to be returned if the netmsg function disposes of the message.
258 netmsg_sync_func(struct netmsg
*msg
)
260 lwkt_replymsg(&msg
->nm_lmsg
, 0);
264 * Return current BGL lock state (1:locked, 0: unlocked)
267 netmsg_service(struct netmsg
*msg
, int mpsafe_mode
, int mplocked
)
270 * Adjust the mplock dynamically.
272 switch (mpsafe_mode
) {
273 case NETMSG_SERVICE_ADAPTIVE
: /* Adaptive BGL */
274 if (msg
->nm_lmsg
.ms_flags
& MSGF_MPSAFE
) {
279 msg
->nm_dispatch(msg
);
280 /* Leave mpunlocked */
284 /* mplocked = 1; not needed */
286 msg
->nm_dispatch(msg
);
289 /* Leave mpunlocked, next msg might be mpsafe */
293 case NETMSG_SERVICE_MPSAFE
: /* No BGL */
298 msg
->nm_dispatch(msg
);
299 /* Leave mpunlocked */
307 msg
->nm_dispatch(msg
);
315 * Generic netmsg service loop. Some protocols may roll their own but all
316 * must do the basic command dispatch function call done here.
319 netmsg_service_loop(void *arg
)
322 int mplocked
, *mpsafe_mode
= arg
;
325 * Thread was started with TDF_MPSAFE
332 while ((msg
= lwkt_waitport(&curthread
->td_msgport
, 0))) {
333 mplocked
= netmsg_service(msg
, *mpsafe_mode
, mplocked
);
338 * Call the netisr directly.
339 * Queueing may be done in the msg port layer at its discretion.
342 netisr_dispatch(int num
, struct mbuf
*m
)
344 /* just queue it for now XXX JH */
345 netisr_queue(num
, m
);
349 * Same as netisr_dispatch(), but always queue.
350 * This is either used in places where we are not confident that
351 * direct dispatch is possible, or where queueing is required.
354 netisr_queue(int num
, struct mbuf
*m
)
357 struct netmsg_packet
*pmsg
;
360 KASSERT((num
> 0 && num
<= (sizeof(netisrs
)/sizeof(netisrs
[0]))),
361 ("%s: bad isr %d", __func__
, num
));
364 if (ni
->ni_handler
== NULL
) {
365 kprintf("%s: unregistered isr %d\n", __func__
, num
);
370 if ((port
= ni
->ni_mport(&m
)) == NULL
)
373 pmsg
= &m
->m_hdr
.mh_netmsg
;
375 netmsg_init(&pmsg
->nm_netmsg
, &netisr_apanic_rport
, NETISR_TO_MSGF(ni
),
378 pmsg
->nm_netmsg
.nm_lmsg
.u
.ms_result
= num
;
379 lwkt_sendmsg(port
, &pmsg
->nm_netmsg
.nm_lmsg
);
384 netisr_register(int num
, pkt_portfn_t mportfn
,
385 pktinfo_portfn_t mportfn_pktinfo
, netisr_fn_t handler
,
390 KASSERT((num
> 0 && num
<= (sizeof(netisrs
)/sizeof(netisrs
[0]))),
391 ("netisr_register: bad isr %d", num
));
394 ni
->ni_mport
= mportfn
;
395 ni
->ni_mport_pktinfo
= mportfn_pktinfo
;
396 ni
->ni_handler
= handler
;
397 ni
->ni_flags
= flags
;
398 netmsg_init(&ni
->ni_netmsg
, &netisr_adone_rport
, NETISR_TO_MSGF(ni
), NULL
);
402 netisr_unregister(int num
)
404 KASSERT((num
> 0 && num
<= (sizeof(netisrs
)/sizeof(netisrs
[0]))),
405 ("unregister_netisr: bad isr number: %d\n", num
));
412 * Return message port for default handler thread on CPU 0.
415 cpu0_portfn(struct mbuf
**mptr
)
417 struct mbuf
*m
= *mptr
;
420 m
->m_pkthdr
.hash
= cpu
;
421 m
->m_flags
|= M_HASH
;
422 return (&netisr_cpu
[cpu
].td_msgport
);
428 return (&netisr_cpu
[cpu
].td_msgport
);
432 * If the current thread is a network protocol thread (TDF_NETWORK),
433 * then return the current thread's message port.
434 * XXX Else, return the current CPU's netisr message port.
439 if (curthread
->td_flags
& TDF_NETWORK
)
440 return &curthread
->td_msgport
;
442 return cpu_portfn(mycpuid
);
447 cpu0_soport(struct socket
*so __unused
, struct sockaddr
*nam __unused
,
448 struct mbuf
**dummy __unused
, int req __unused
)
450 return (&netisr_cpu
[0].td_msgport
);
454 cpu0_ctlport(int cmd __unused
, struct sockaddr
*sa __unused
,
455 void *extra __unused
)
457 return (&netisr_cpu
[0].td_msgport
);
461 sync_soport(struct socket
*so __unused
, struct sockaddr
*nam __unused
,
462 struct mbuf
**dummy __unused
, int req __unused
)
464 return (&netisr_sync_port
);
468 * schednetisr() is used to call the netisr handler from the appropriate
469 * netisr thread for polling and other purposes.
471 * This function may be called from a hard interrupt or IPI and must be
472 * MP SAFE and non-blocking. We use a fixed per-cpu message instead of
473 * trying to allocate one. We must get ourselves onto the target cpu
474 * to safely check the MSGF_DONE bit on the message but since the message
475 * will be sent to that cpu anyway this does not add any extra work beyond
476 * what lwkt_sendmsg() would have already had to do to schedule the target
480 schednetisr_remote(void *data
)
482 int num
= (int)(intptr_t)data
;
483 struct netisr
*ni
= &netisrs
[num
];
484 lwkt_port_t port
= &netisr_cpu
[0].td_msgport
;
487 pmsg
= &netisrs
[num
].ni_netmsg
;
489 if (pmsg
->nm_lmsg
.ms_flags
& MSGF_DONE
) {
490 netmsg_init(pmsg
, &netisr_adone_rport
, NETISR_TO_MSGF(ni
),
492 pmsg
->nm_lmsg
.u
.ms_result
= num
;
493 lwkt_sendmsg(port
, &pmsg
->nm_lmsg
);
501 KASSERT((num
> 0 && num
<= (sizeof(netisrs
)/sizeof(netisrs
[0]))),
502 ("schednetisr: bad isr %d", num
));
504 if (mycpu
->gd_cpuid
!= 0) {
505 lwkt_send_ipiq(globaldata_find(0),
506 schednetisr_remote
, (void *)(intptr_t)num
);
508 schednetisr_remote((void *)(intptr_t)num
);
511 schednetisr_remote((void *)(intptr_t)num
);
516 netisr_find_port(int num
, struct mbuf
**m0
)
520 struct mbuf
*m
= *m0
;
524 KASSERT((num
> 0 && num
<= (sizeof(netisrs
)/sizeof(netisrs
[0]))),
525 ("%s: bad isr %d", __func__
, num
));
528 if (ni
->ni_mport
== NULL
) {
529 kprintf("%s: unregistered isr %d\n", __func__
, num
);
534 if ((port
= ni
->ni_mport(&m
)) == NULL
)
542 netisr_run(int num
, struct mbuf
*m
)
545 struct netmsg_packet
*pmsg
;
547 KASSERT((num
> 0 && num
<= (sizeof(netisrs
)/sizeof(netisrs
[0]))),
548 ("%s: bad isr %d", __func__
, num
));
551 if (ni
->ni_handler
== NULL
) {
552 kprintf("%s: unregistered isr %d\n", __func__
, num
);
557 pmsg
= &m
->m_hdr
.mh_netmsg
;
559 netmsg_init(&pmsg
->nm_netmsg
, &netisr_apanic_rport
, 0, ni
->ni_handler
);
561 pmsg
->nm_netmsg
.nm_lmsg
.u
.ms_result
= num
;
563 NETISR_GET_MPLOCK(ni
);
564 ni
->ni_handler(&pmsg
->nm_netmsg
);
565 NETISR_REL_MPLOCK(ni
);
569 pktinfo_portfn_cpu0(const struct pktinfo
*dummy __unused
,
572 m
->m_pkthdr
.hash
= 0;
573 return &netisr_cpu
[0].td_msgport
;
577 pktinfo_portfn_notsupp(const struct pktinfo
*dummy __unused
,
578 struct mbuf
*m __unused
)
584 netisr_find_pktinfo_port(const struct pktinfo
*pi
, struct mbuf
*m
)
587 int num
= pi
->pi_netisr
;
589 KASSERT(m
->m_flags
& M_HASH
, ("packet does not contain hash\n"));
590 KASSERT((num
> 0 && num
<= (sizeof(netisrs
)/sizeof(netisrs
[0]))),
591 ("%s: bad isr %d", __func__
, num
));
594 if (ni
->ni_mport_pktinfo
== NULL
) {
595 kprintf("%s: unregistered isr %d\n", __func__
, num
);
598 return ni
->ni_mport_pktinfo(pi
, m
);