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_adone_rport
;
83 lwkt_port netisr_apanic_rport
;
84 lwkt_port netisr_sync_port
;
86 static int (*netmsg_fwd_port_fn
)(lwkt_port_t
, lwkt_msg_t
);
88 SYSCTL_NODE(_net
, OID_AUTO
, netisr
, CTLFLAG_RW
, 0, "netisr");
91 * netisr_afree_rport replymsg function, only used to handle async
92 * messages which the sender has abandoned to their fate.
95 netisr_autofree_reply(lwkt_port_t port
, lwkt_msg_t msg
)
97 kfree(msg
, M_LWKTMSG
);
101 * We need a custom putport function to handle the case where the
102 * message target is the current thread's message port. This case
103 * can occur when the TCP or UDP stack does a direct callback to NFS and NFS
104 * then turns around and executes a network operation synchronously.
106 * To prevent deadlocking, we must execute these self-referential messages
107 * synchronously, effectively turning the message into a glorified direct
108 * procedure call back into the protocol stack. The operation must be
109 * complete on return or we will deadlock, so panic if it isn't.
111 * However, the target function is under no obligation to immediately
112 * reply the message. It may forward it elsewhere.
115 netmsg_put_port(lwkt_port_t port
, lwkt_msg_t lmsg
)
117 netmsg_base_t nmsg
= (void *)lmsg
;
119 if ((lmsg
->ms_flags
& MSGF_SYNC
) && port
== &curthread
->td_msgport
) {
120 nmsg
->nm_dispatch((netmsg_t
)nmsg
);
123 return(netmsg_fwd_port_fn(port
, lmsg
));
128 * UNIX DOMAIN sockets still have to run their uipc functions synchronously,
129 * because they depend on the user proc context for a number of things
130 * (like creds) which we have not yet incorporated into the message structure.
132 * However, we maintain or message/port abstraction. Having a special
133 * synchronous port which runs the commands synchronously gives us the
134 * ability to serialize operations in one place later on when we start
138 netmsg_sync_putport(lwkt_port_t port
, lwkt_msg_t lmsg
)
140 netmsg_base_t nmsg
= (void *)lmsg
;
142 KKASSERT((lmsg
->ms_flags
& MSGF_DONE
) == 0);
144 lmsg
->ms_target_port
= port
; /* required for abort */
145 nmsg
->nm_dispatch((netmsg_t
)nmsg
);
154 TAILQ_INIT(&netreglist
);
155 TAILQ_INIT(&netrulist
);
158 * Create default per-cpu threads for generic protocol handling.
160 for (i
= 0; i
< ncpus
; ++i
) {
161 lwkt_create(netmsg_service_loop
, NULL
, NULL
,
162 &netisr_cpu
[i
], TDF_STOPREQ
, i
,
164 netmsg_service_port_init(&netisr_cpu
[i
].td_msgport
);
165 lwkt_schedule(&netisr_cpu
[i
]);
169 * The netisr_afree_rport is a special reply port which automatically
170 * frees the replied message. The netisr_adone_rport simply marks
171 * the message as being done. The netisr_apanic_rport panics if
172 * the message is replied to.
174 lwkt_initport_replyonly(&netisr_afree_rport
, netisr_autofree_reply
);
175 lwkt_initport_replyonly_null(&netisr_adone_rport
);
176 lwkt_initport_panic(&netisr_apanic_rport
);
179 * The netisr_syncport is a special port which executes the message
180 * synchronously and waits for it if EASYNC is returned.
182 lwkt_initport_putonly(&netisr_sync_port
, netmsg_sync_putport
);
185 SYSINIT(netisr
, SI_SUB_PRE_DRIVERS
, SI_ORDER_FIRST
, netisr_init
, NULL
);
188 * Finish initializing the message port for a netmsg service. This also
189 * registers the port for synchronous cleanup operations such as when an
190 * ifnet is being destroyed. There is no deregistration API yet.
193 netmsg_service_port_init(lwkt_port_t port
)
195 struct netmsg_port_registration
*reg
;
198 * Override the putport function. Our custom function checks for
199 * self-references and executes such commands synchronously.
201 if (netmsg_fwd_port_fn
== NULL
)
202 netmsg_fwd_port_fn
= port
->mp_putport
;
203 KKASSERT(netmsg_fwd_port_fn
== port
->mp_putport
);
204 port
->mp_putport
= netmsg_put_port
;
207 * Keep track of ports using the netmsg API so we can synchronize
208 * certain operations (such as freeing an ifnet structure) across all
211 reg
= kmalloc(sizeof(*reg
), M_TEMP
, M_WAITOK
|M_ZERO
);
212 reg
->npr_port
= port
;
213 TAILQ_INSERT_TAIL(&netreglist
, reg
, npr_entry
);
217 * This function synchronizes the caller with all netmsg services. For
218 * example, if an interface is being removed we must make sure that all
219 * packets related to that interface complete processing before the structure
220 * can actually be freed. This sort of synchronization is an alternative to
221 * ref-counting the netif, removing the ref counting overhead in favor of
222 * placing additional overhead in the netif freeing sequence (where it is
226 netmsg_service_sync(void)
228 struct netmsg_port_registration
*reg
;
229 struct netmsg_base smsg
;
231 netmsg_init(&smsg
, NULL
, &curthread
->td_msgport
, 0, netmsg_sync_func
);
233 TAILQ_FOREACH(reg
, &netreglist
, npr_entry
) {
234 lwkt_domsg(reg
->npr_port
, &smsg
.lmsg
, 0);
239 * The netmsg function simply replies the message. API semantics require
240 * EASYNC to be returned if the netmsg function disposes of the message.
243 netmsg_sync_func(netmsg_t msg
)
245 lwkt_replymsg(&msg
->lmsg
, 0);
249 * Generic netmsg service loop. Some protocols may roll their own but all
250 * must do the basic command dispatch function call done here.
253 netmsg_service_loop(void *arg
)
255 struct netmsg_rollup
*ru
;
257 thread_t td
= curthread
;;
260 while ((msg
= lwkt_waitport(&td
->td_msgport
, 0))) {
262 * Run up to 512 pending netmsgs.
266 KASSERT(msg
->nm_dispatch
!= NULL
,
267 ("netmsg_service isr %d badmsg\n",
268 msg
->lmsg
.u
.ms_result
));
270 msg
->nm_so
->so_port
!= &td
->td_msgport
) {
272 * Sockets undergoing connect or disconnect
273 * ops can change ports on us. Chase the
276 kprintf("netmsg_service_loop: Warning, "
277 "port changed so=%p\n", msg
->nm_so
);
278 lwkt_forwardmsg(msg
->nm_so
->so_port
,
282 * We are on the correct port, dispatch it.
284 msg
->nm_dispatch((netmsg_t
)msg
);
288 } while ((msg
= lwkt_getport(&td
->td_msgport
)) != NULL
);
291 * Run all registered rollup functions for this cpu
292 * (e.g. tcp_willblock()).
294 TAILQ_FOREACH(ru
, &netrulist
, ru_entry
)
300 * Forward a packet to a netisr service function.
302 * If the packet has not been assigned to a protocol thread we call
303 * the port characterization function to assign it. The caller must
304 * clear M_HASH (or not have set it in the first place) if the caller
305 * wishes the packet to be recharacterized.
308 netisr_queue(int num
, struct mbuf
*m
)
311 struct netmsg_packet
*pmsg
;
314 KASSERT((num
> 0 && num
<= (sizeof(netisrs
)/sizeof(netisrs
[0]))),
315 ("Bad isr %d", num
));
318 if (ni
->ni_handler
== NULL
) {
319 kprintf("Unregistered isr %d\n", num
);
325 * Figure out which protocol thread to send to. This does not
326 * have to be perfect but performance will be really good if it
327 * is correct. Major protocol inputs such as ip_input() will
328 * re-characterize the packet as necessary.
330 if ((m
->m_flags
& M_HASH
) == 0) {
336 if ((m
->m_flags
& M_HASH
) == 0) {
337 kprintf("netisr_queue(%d): packet hash failed\n", num
);
344 * Get the protocol port based on the packet hash, initialize
345 * the netmsg, and send it off.
347 port
= cpu_portfn(m
->m_pkthdr
.hash
);
348 pmsg
= &m
->m_hdr
.mh_netmsg
;
349 netmsg_init(&pmsg
->base
, NULL
, &netisr_apanic_rport
,
352 pmsg
->base
.lmsg
.u
.ms_result
= num
;
353 lwkt_sendmsg(port
, &pmsg
->base
.lmsg
);
359 * Pre-characterization of a deeper portion of the packet for the
362 * The base of the ISR type (e.g. IP) that we want to characterize is
363 * at (hoff) relative to the beginning of the mbuf. This allows
364 * e.g. ether_input_chain() to not have to adjust the m_data/m_len.
367 netisr_characterize(int num
, struct mbuf
**mp
, int hoff
)
378 if (num
< 0 || num
>= NETISR_MAX
) {
379 if (num
== NETISR_MAX
) {
380 m
->m_flags
|= M_HASH
;
381 m
->m_pkthdr
.hash
= 0;
384 panic("Bad isr %d", num
);
391 if (ni
->ni_handler
== NULL
) {
392 kprintf("Unregistered isr %d\n", num
);
398 * Characterize the packet
400 if ((m
->m_flags
& M_HASH
) == 0) {
401 ni
->ni_cpufn(mp
, hoff
);
403 if (m
&& (m
->m_flags
& M_HASH
) == 0)
404 kprintf("netisr_queue(%d): packet hash failed\n", num
);
409 netisr_register(int num
, netisr_fn_t handler
, netisr_cpufn_t cpufn
)
413 KASSERT((num
> 0 && num
<= (sizeof(netisrs
)/sizeof(netisrs
[0]))),
414 ("netisr_register: bad isr %d", num
));
415 KKASSERT(handler
!= NULL
);
422 ni
->ni_handler
= handler
;
423 ni
->ni_cpufn
= cpufn
;
424 netmsg_init(&ni
->ni_netmsg
, NULL
, &netisr_adone_rport
, 0, NULL
);
428 netisr_register_rollup(netisr_ru_t ru_func
)
430 struct netmsg_rollup
*ru
;
432 ru
= kmalloc(sizeof(*ru
), M_TEMP
, M_WAITOK
|M_ZERO
);
433 ru
->ru_func
= ru_func
;
434 TAILQ_INSERT_TAIL(&netrulist
, ru
, ru_entry
);
438 * Return the message port for the general protocol message servicing
439 * thread for a particular cpu.
444 KKASSERT(cpu
>= 0 && cpu
< ncpus
);
445 return (&netisr_cpu
[cpu
].td_msgport
);
449 * Return the current cpu's network protocol thread.
454 return(cpu_portfn(mycpu
->gd_cpuid
));
458 * Return a default protocol control message processing thread port
461 cpu0_ctlport(int cmd __unused
, struct sockaddr
*sa __unused
,
462 void *extra __unused
)
464 return (&netisr_cpu
[0].td_msgport
);
468 * This is a default netisr packet characterization function which
469 * sets M_HASH. If a netisr is registered with a NULL cpufn function
470 * this one is assigned.
472 * This function makes no attempt to validate the packet.
475 cpu0_cpufn(struct mbuf
**mp
, int hoff __unused
)
477 struct mbuf
*m
= *mp
;
479 m
->m_flags
|= M_HASH
;
480 m
->m_pkthdr
.hash
= 0;
484 * schednetisr() is used to call the netisr handler from the appropriate
485 * netisr thread for polling and other purposes.
487 * This function may be called from a hard interrupt or IPI and must be
488 * MP SAFE and non-blocking. We use a fixed per-cpu message instead of
489 * trying to allocate one. We must get ourselves onto the target cpu
490 * to safely check the MSGF_DONE bit on the message but since the message
491 * will be sent to that cpu anyway this does not add any extra work beyond
492 * what lwkt_sendmsg() would have already had to do to schedule the target
496 schednetisr_remote(void *data
)
498 int num
= (int)(intptr_t)data
;
499 struct netisr
*ni
= &netisrs
[num
];
500 lwkt_port_t port
= &netisr_cpu
[0].td_msgport
;
503 pmsg
= &netisrs
[num
].ni_netmsg
;
504 if (pmsg
->lmsg
.ms_flags
& MSGF_DONE
) {
505 netmsg_init(pmsg
, NULL
, &netisr_adone_rport
, 0, ni
->ni_handler
);
506 pmsg
->lmsg
.u
.ms_result
= num
;
507 lwkt_sendmsg(port
, &pmsg
->lmsg
);
514 KASSERT((num
> 0 && num
<= (sizeof(netisrs
)/sizeof(netisrs
[0]))),
515 ("schednetisr: bad isr %d", num
));
516 KKASSERT(netisrs
[num
].ni_handler
!= NULL
);
518 if (mycpu
->gd_cpuid
!= 0) {
519 lwkt_send_ipiq(globaldata_find(0),
520 schednetisr_remote
, (void *)(intptr_t)num
);
523 schednetisr_remote((void *)(intptr_t)num
);
528 schednetisr_remote((void *)(intptr_t)num
);