2 * linux/net/sunrpc/svc_xprt.c
4 * Author: Tom Tucker <tom@opengridcomputing.com>
7 #include <linux/sched.h>
8 #include <linux/errno.h>
9 #include <linux/freezer.h>
10 #include <linux/kthread.h>
11 #include <linux/slab.h>
13 #include <linux/sunrpc/stats.h>
14 #include <linux/sunrpc/svc_xprt.h>
15 #include <linux/sunrpc/svcsock.h>
16 #include <linux/sunrpc/xprt.h>
17 #include <linux/module.h>
19 #define RPCDBG_FACILITY RPCDBG_SVCXPRT
21 static struct svc_deferred_req
*svc_deferred_dequeue(struct svc_xprt
*xprt
);
22 static int svc_deferred_recv(struct svc_rqst
*rqstp
);
23 static struct cache_deferred_req
*svc_defer(struct cache_req
*req
);
24 static void svc_age_temp_xprts(unsigned long closure
);
25 static void svc_delete_xprt(struct svc_xprt
*xprt
);
27 /* apparently the "standard" is that clients close
28 * idle connections after 5 minutes, servers after
30 * http://www.connectathon.org/talks96/nfstcp.pdf
32 static int svc_conn_age_period
= 6*60;
34 /* List of registered transport classes */
35 static DEFINE_SPINLOCK(svc_xprt_class_lock
);
36 static LIST_HEAD(svc_xprt_class_list
);
38 /* SMP locking strategy:
40 * svc_pool->sp_lock protects most of the fields of that pool.
41 * svc_serv->sv_lock protects sv_tempsocks, sv_permsocks, sv_tmpcnt.
42 * when both need to be taken (rare), svc_serv->sv_lock is first.
43 * BKL protects svc_serv->sv_nrthread.
44 * svc_sock->sk_lock protects the svc_sock->sk_deferred list
45 * and the ->sk_info_authunix cache.
47 * The XPT_BUSY bit in xprt->xpt_flags prevents a transport being
48 * enqueued multiply. During normal transport processing this bit
49 * is set by svc_xprt_enqueue and cleared by svc_xprt_received.
50 * Providers should not manipulate this bit directly.
52 * Some flags can be set to certain values at any time
53 * providing that certain rules are followed:
56 * - Can be set or cleared at any time.
57 * - After a set, svc_xprt_enqueue must be called to enqueue
58 * the transport for processing.
59 * - After a clear, the transport must be read/accepted.
60 * If this succeeds, it must be set again.
62 * - Can set at any time. It is never cleared.
64 * - Can only be set while XPT_BUSY is held which ensures
65 * that no other thread will be using the transport or will
66 * try to set XPT_DEAD.
69 int svc_reg_xprt_class(struct svc_xprt_class
*xcl
)
71 struct svc_xprt_class
*cl
;
74 dprintk("svc: Adding svc transport class '%s'\n", xcl
->xcl_name
);
76 INIT_LIST_HEAD(&xcl
->xcl_list
);
77 spin_lock(&svc_xprt_class_lock
);
78 /* Make sure there isn't already a class with the same name */
79 list_for_each_entry(cl
, &svc_xprt_class_list
, xcl_list
) {
80 if (strcmp(xcl
->xcl_name
, cl
->xcl_name
) == 0)
83 list_add_tail(&xcl
->xcl_list
, &svc_xprt_class_list
);
86 spin_unlock(&svc_xprt_class_lock
);
89 EXPORT_SYMBOL_GPL(svc_reg_xprt_class
);
91 void svc_unreg_xprt_class(struct svc_xprt_class
*xcl
)
93 dprintk("svc: Removing svc transport class '%s'\n", xcl
->xcl_name
);
94 spin_lock(&svc_xprt_class_lock
);
95 list_del_init(&xcl
->xcl_list
);
96 spin_unlock(&svc_xprt_class_lock
);
98 EXPORT_SYMBOL_GPL(svc_unreg_xprt_class
);
101 * Format the transport list for printing
103 int svc_print_xprts(char *buf
, int maxlen
)
105 struct svc_xprt_class
*xcl
;
110 spin_lock(&svc_xprt_class_lock
);
111 list_for_each_entry(xcl
, &svc_xprt_class_list
, xcl_list
) {
114 sprintf(tmpstr
, "%s %d\n", xcl
->xcl_name
, xcl
->xcl_max_payload
);
115 slen
= strlen(tmpstr
);
116 if (len
+ slen
> maxlen
)
121 spin_unlock(&svc_xprt_class_lock
);
126 static void svc_xprt_free(struct kref
*kref
)
128 struct svc_xprt
*xprt
=
129 container_of(kref
, struct svc_xprt
, xpt_ref
);
130 struct module
*owner
= xprt
->xpt_class
->xcl_owner
;
131 if (test_bit(XPT_CACHE_AUTH
, &xprt
->xpt_flags
))
132 svcauth_unix_info_release(xprt
);
133 put_net(xprt
->xpt_net
);
134 /* See comment on corresponding get in xs_setup_bc_tcp(): */
135 if (xprt
->xpt_bc_xprt
)
136 xprt_put(xprt
->xpt_bc_xprt
);
137 xprt
->xpt_ops
->xpo_free(xprt
);
141 void svc_xprt_put(struct svc_xprt
*xprt
)
143 kref_put(&xprt
->xpt_ref
, svc_xprt_free
);
145 EXPORT_SYMBOL_GPL(svc_xprt_put
);
148 * Called by transport drivers to initialize the transport independent
149 * portion of the transport instance.
151 void svc_xprt_init(struct net
*net
, struct svc_xprt_class
*xcl
,
152 struct svc_xprt
*xprt
, struct svc_serv
*serv
)
154 memset(xprt
, 0, sizeof(*xprt
));
155 xprt
->xpt_class
= xcl
;
156 xprt
->xpt_ops
= xcl
->xcl_ops
;
157 kref_init(&xprt
->xpt_ref
);
158 xprt
->xpt_server
= serv
;
159 INIT_LIST_HEAD(&xprt
->xpt_list
);
160 INIT_LIST_HEAD(&xprt
->xpt_ready
);
161 INIT_LIST_HEAD(&xprt
->xpt_deferred
);
162 INIT_LIST_HEAD(&xprt
->xpt_users
);
163 mutex_init(&xprt
->xpt_mutex
);
164 spin_lock_init(&xprt
->xpt_lock
);
165 set_bit(XPT_BUSY
, &xprt
->xpt_flags
);
166 rpc_init_wait_queue(&xprt
->xpt_bc_pending
, "xpt_bc_pending");
167 xprt
->xpt_net
= get_net(net
);
169 EXPORT_SYMBOL_GPL(svc_xprt_init
);
171 static struct svc_xprt
*__svc_xpo_create(struct svc_xprt_class
*xcl
,
172 struct svc_serv
*serv
,
175 const unsigned short port
,
178 struct sockaddr_in sin
= {
179 .sin_family
= AF_INET
,
180 .sin_addr
.s_addr
= htonl(INADDR_ANY
),
181 .sin_port
= htons(port
),
183 #if IS_ENABLED(CONFIG_IPV6)
184 struct sockaddr_in6 sin6
= {
185 .sin6_family
= AF_INET6
,
186 .sin6_addr
= IN6ADDR_ANY_INIT
,
187 .sin6_port
= htons(port
),
190 struct sockaddr
*sap
;
195 sap
= (struct sockaddr
*)&sin
;
198 #if IS_ENABLED(CONFIG_IPV6)
200 sap
= (struct sockaddr
*)&sin6
;
205 return ERR_PTR(-EAFNOSUPPORT
);
208 return xcl
->xcl_ops
->xpo_create(serv
, net
, sap
, len
, flags
);
211 int svc_create_xprt(struct svc_serv
*serv
, const char *xprt_name
,
212 struct net
*net
, const int family
,
213 const unsigned short port
, int flags
)
215 struct svc_xprt_class
*xcl
;
217 dprintk("svc: creating transport %s[%d]\n", xprt_name
, port
);
218 spin_lock(&svc_xprt_class_lock
);
219 list_for_each_entry(xcl
, &svc_xprt_class_list
, xcl_list
) {
220 struct svc_xprt
*newxprt
;
221 unsigned short newport
;
223 if (strcmp(xprt_name
, xcl
->xcl_name
))
226 if (!try_module_get(xcl
->xcl_owner
))
229 spin_unlock(&svc_xprt_class_lock
);
230 newxprt
= __svc_xpo_create(xcl
, serv
, net
, family
, port
, flags
);
231 if (IS_ERR(newxprt
)) {
232 module_put(xcl
->xcl_owner
);
233 return PTR_ERR(newxprt
);
236 clear_bit(XPT_TEMP
, &newxprt
->xpt_flags
);
237 spin_lock_bh(&serv
->sv_lock
);
238 list_add(&newxprt
->xpt_list
, &serv
->sv_permsocks
);
239 spin_unlock_bh(&serv
->sv_lock
);
240 newport
= svc_xprt_local_port(newxprt
);
241 clear_bit(XPT_BUSY
, &newxprt
->xpt_flags
);
245 spin_unlock(&svc_xprt_class_lock
);
246 dprintk("svc: transport %s not found\n", xprt_name
);
248 /* This errno is exposed to user space. Provide a reasonable
249 * perror msg for a bad transport. */
250 return -EPROTONOSUPPORT
;
252 EXPORT_SYMBOL_GPL(svc_create_xprt
);
255 * Copy the local and remote xprt addresses to the rqstp structure
257 void svc_xprt_copy_addrs(struct svc_rqst
*rqstp
, struct svc_xprt
*xprt
)
259 memcpy(&rqstp
->rq_addr
, &xprt
->xpt_remote
, xprt
->xpt_remotelen
);
260 rqstp
->rq_addrlen
= xprt
->xpt_remotelen
;
263 * Destination address in request is needed for binding the
264 * source address in RPC replies/callbacks later.
266 memcpy(&rqstp
->rq_daddr
, &xprt
->xpt_local
, xprt
->xpt_locallen
);
267 rqstp
->rq_daddrlen
= xprt
->xpt_locallen
;
269 EXPORT_SYMBOL_GPL(svc_xprt_copy_addrs
);
272 * svc_print_addr - Format rq_addr field for printing
273 * @rqstp: svc_rqst struct containing address to print
274 * @buf: target buffer for formatted address
275 * @len: length of target buffer
278 char *svc_print_addr(struct svc_rqst
*rqstp
, char *buf
, size_t len
)
280 return __svc_print_addr(svc_addr(rqstp
), buf
, len
);
282 EXPORT_SYMBOL_GPL(svc_print_addr
);
285 * Queue up an idle server thread. Must have pool->sp_lock held.
286 * Note: this is really a stack rather than a queue, so that we only
287 * use as many different threads as we need, and the rest don't pollute
290 static void svc_thread_enqueue(struct svc_pool
*pool
, struct svc_rqst
*rqstp
)
292 list_add(&rqstp
->rq_list
, &pool
->sp_threads
);
296 * Dequeue an nfsd thread. Must have pool->sp_lock held.
298 static void svc_thread_dequeue(struct svc_pool
*pool
, struct svc_rqst
*rqstp
)
300 list_del(&rqstp
->rq_list
);
303 static bool svc_xprt_has_something_to_do(struct svc_xprt
*xprt
)
305 if (xprt
->xpt_flags
& ((1<<XPT_CONN
)|(1<<XPT_CLOSE
)))
307 if (xprt
->xpt_flags
& ((1<<XPT_DATA
)|(1<<XPT_DEFERRED
)))
308 return xprt
->xpt_ops
->xpo_has_wspace(xprt
);
313 * Queue up a transport with data pending. If there are idle nfsd
314 * processes, wake 'em up.
317 void svc_xprt_enqueue(struct svc_xprt
*xprt
)
319 struct svc_serv
*serv
= xprt
->xpt_server
;
320 struct svc_pool
*pool
;
321 struct svc_rqst
*rqstp
;
324 if (!svc_xprt_has_something_to_do(xprt
))
328 pool
= svc_pool_for_cpu(xprt
->xpt_server
, cpu
);
331 spin_lock_bh(&pool
->sp_lock
);
333 if (!list_empty(&pool
->sp_threads
) &&
334 !list_empty(&pool
->sp_sockets
))
337 "threads and transports both waiting??\n");
339 pool
->sp_stats
.packets
++;
341 /* Mark transport as busy. It will remain in this state until
342 * the provider calls svc_xprt_received. We update XPT_BUSY
343 * atomically because it also guards against trying to enqueue
344 * the transport twice.
346 if (test_and_set_bit(XPT_BUSY
, &xprt
->xpt_flags
)) {
347 /* Don't enqueue transport while already enqueued */
348 dprintk("svc: transport %p busy, not enqueued\n", xprt
);
352 if (!list_empty(&pool
->sp_threads
)) {
353 rqstp
= list_entry(pool
->sp_threads
.next
,
356 dprintk("svc: transport %p served by daemon %p\n",
358 svc_thread_dequeue(pool
, rqstp
);
361 "svc_xprt_enqueue: server %p, rq_xprt=%p!\n",
362 rqstp
, rqstp
->rq_xprt
);
363 rqstp
->rq_xprt
= xprt
;
365 rqstp
->rq_reserved
= serv
->sv_max_mesg
;
366 atomic_add(rqstp
->rq_reserved
, &xprt
->xpt_reserved
);
367 pool
->sp_stats
.threads_woken
++;
368 wake_up(&rqstp
->rq_wait
);
370 dprintk("svc: transport %p put into queue\n", xprt
);
371 list_add_tail(&xprt
->xpt_ready
, &pool
->sp_sockets
);
372 pool
->sp_stats
.sockets_queued
++;
376 spin_unlock_bh(&pool
->sp_lock
);
378 EXPORT_SYMBOL_GPL(svc_xprt_enqueue
);
381 * Dequeue the first transport. Must be called with the pool->sp_lock held.
383 static struct svc_xprt
*svc_xprt_dequeue(struct svc_pool
*pool
)
385 struct svc_xprt
*xprt
;
387 if (list_empty(&pool
->sp_sockets
))
390 xprt
= list_entry(pool
->sp_sockets
.next
,
391 struct svc_xprt
, xpt_ready
);
392 list_del_init(&xprt
->xpt_ready
);
394 dprintk("svc: transport %p dequeued, inuse=%d\n",
395 xprt
, atomic_read(&xprt
->xpt_ref
.refcount
));
401 * svc_xprt_received conditionally queues the transport for processing
402 * by another thread. The caller must hold the XPT_BUSY bit and must
403 * not thereafter touch transport data.
405 * Note: XPT_DATA only gets cleared when a read-attempt finds no (or
406 * insufficient) data.
408 void svc_xprt_received(struct svc_xprt
*xprt
)
410 BUG_ON(!test_bit(XPT_BUSY
, &xprt
->xpt_flags
));
411 /* As soon as we clear busy, the xprt could be closed and
412 * 'put', so we need a reference to call svc_xprt_enqueue with:
415 clear_bit(XPT_BUSY
, &xprt
->xpt_flags
);
416 svc_xprt_enqueue(xprt
);
419 EXPORT_SYMBOL_GPL(svc_xprt_received
);
422 * svc_reserve - change the space reserved for the reply to a request.
423 * @rqstp: The request in question
424 * @space: new max space to reserve
426 * Each request reserves some space on the output queue of the transport
427 * to make sure the reply fits. This function reduces that reserved
428 * space to be the amount of space used already, plus @space.
431 void svc_reserve(struct svc_rqst
*rqstp
, int space
)
433 space
+= rqstp
->rq_res
.head
[0].iov_len
;
435 if (space
< rqstp
->rq_reserved
) {
436 struct svc_xprt
*xprt
= rqstp
->rq_xprt
;
437 atomic_sub((rqstp
->rq_reserved
- space
), &xprt
->xpt_reserved
);
438 rqstp
->rq_reserved
= space
;
440 svc_xprt_enqueue(xprt
);
443 EXPORT_SYMBOL_GPL(svc_reserve
);
445 static void svc_xprt_release(struct svc_rqst
*rqstp
)
447 struct svc_xprt
*xprt
= rqstp
->rq_xprt
;
449 rqstp
->rq_xprt
->xpt_ops
->xpo_release_rqst(rqstp
);
451 kfree(rqstp
->rq_deferred
);
452 rqstp
->rq_deferred
= NULL
;
454 svc_free_res_pages(rqstp
);
455 rqstp
->rq_res
.page_len
= 0;
456 rqstp
->rq_res
.page_base
= 0;
458 /* Reset response buffer and release
460 * But first, check that enough space was reserved
461 * for the reply, otherwise we have a bug!
463 if ((rqstp
->rq_res
.len
) > rqstp
->rq_reserved
)
464 printk(KERN_ERR
"RPC request reserved %d but used %d\n",
468 rqstp
->rq_res
.head
[0].iov_len
= 0;
469 svc_reserve(rqstp
, 0);
470 rqstp
->rq_xprt
= NULL
;
476 * External function to wake up a server waiting for data
477 * This really only makes sense for services like lockd
478 * which have exactly one thread anyway.
480 void svc_wake_up(struct svc_serv
*serv
)
482 struct svc_rqst
*rqstp
;
484 struct svc_pool
*pool
;
486 for (i
= 0; i
< serv
->sv_nrpools
; i
++) {
487 pool
= &serv
->sv_pools
[i
];
489 spin_lock_bh(&pool
->sp_lock
);
490 if (!list_empty(&pool
->sp_threads
)) {
491 rqstp
= list_entry(pool
->sp_threads
.next
,
494 dprintk("svc: daemon %p woken up.\n", rqstp
);
496 svc_thread_dequeue(pool, rqstp);
497 rqstp->rq_xprt = NULL;
499 wake_up(&rqstp
->rq_wait
);
501 spin_unlock_bh(&pool
->sp_lock
);
504 EXPORT_SYMBOL_GPL(svc_wake_up
);
506 int svc_port_is_privileged(struct sockaddr
*sin
)
508 switch (sin
->sa_family
) {
510 return ntohs(((struct sockaddr_in
*)sin
)->sin_port
)
513 return ntohs(((struct sockaddr_in6
*)sin
)->sin6_port
)
521 * Make sure that we don't have too many active connections. If we have,
522 * something must be dropped. It's not clear what will happen if we allow
523 * "too many" connections, but when dealing with network-facing software,
524 * we have to code defensively. Here we do that by imposing hard limits.
526 * There's no point in trying to do random drop here for DoS
527 * prevention. The NFS clients does 1 reconnect in 15 seconds. An
528 * attacker can easily beat that.
530 * The only somewhat efficient mechanism would be if drop old
531 * connections from the same IP first. But right now we don't even
532 * record the client IP in svc_sock.
534 * single-threaded services that expect a lot of clients will probably
535 * need to set sv_maxconn to override the default value which is based
536 * on the number of threads
538 static void svc_check_conn_limits(struct svc_serv
*serv
)
540 unsigned int limit
= serv
->sv_maxconn
? serv
->sv_maxconn
:
541 (serv
->sv_nrthreads
+3) * 20;
543 if (serv
->sv_tmpcnt
> limit
) {
544 struct svc_xprt
*xprt
= NULL
;
545 spin_lock_bh(&serv
->sv_lock
);
546 if (!list_empty(&serv
->sv_tempsocks
)) {
547 /* Try to help the admin */
548 net_notice_ratelimited("%s: too many open connections, consider increasing the %s\n",
549 serv
->sv_name
, serv
->sv_maxconn
?
550 "max number of connections" :
551 "number of threads");
553 * Always select the oldest connection. It's not fair,
556 xprt
= list_entry(serv
->sv_tempsocks
.prev
,
559 set_bit(XPT_CLOSE
, &xprt
->xpt_flags
);
562 spin_unlock_bh(&serv
->sv_lock
);
565 svc_xprt_enqueue(xprt
);
572 * Receive the next request on any transport. This code is carefully
573 * organised not to touch any cachelines in the shared svc_serv
574 * structure, only cachelines in the local svc_pool.
576 int svc_recv(struct svc_rqst
*rqstp
, long timeout
)
578 struct svc_xprt
*xprt
= NULL
;
579 struct svc_serv
*serv
= rqstp
->rq_server
;
580 struct svc_pool
*pool
= rqstp
->rq_pool
;
584 DECLARE_WAITQUEUE(wait
, current
);
587 dprintk("svc: server %p waiting for data (to = %ld)\n",
592 "svc_recv: service %p, transport not NULL!\n",
594 if (waitqueue_active(&rqstp
->rq_wait
))
596 "svc_recv: service %p, wait queue active!\n",
599 /* now allocate needed pages. If we get a failure, sleep briefly */
600 pages
= (serv
->sv_max_mesg
+ PAGE_SIZE
) / PAGE_SIZE
;
601 for (i
= 0; i
< pages
; i
++)
602 while (rqstp
->rq_pages
[i
] == NULL
) {
603 struct page
*p
= alloc_page(GFP_KERNEL
);
605 set_current_state(TASK_INTERRUPTIBLE
);
606 if (signalled() || kthread_should_stop()) {
607 set_current_state(TASK_RUNNING
);
610 schedule_timeout(msecs_to_jiffies(500));
612 rqstp
->rq_pages
[i
] = p
;
614 rqstp
->rq_pages
[i
++] = NULL
; /* this might be seen in nfs_read_actor */
615 BUG_ON(pages
>= RPCSVC_MAXPAGES
);
617 /* Make arg->head point to first page and arg->pages point to rest */
618 arg
= &rqstp
->rq_arg
;
619 arg
->head
[0].iov_base
= page_address(rqstp
->rq_pages
[0]);
620 arg
->head
[0].iov_len
= PAGE_SIZE
;
621 arg
->pages
= rqstp
->rq_pages
+ 1;
623 /* save at least one page for response */
624 arg
->page_len
= (pages
-2)*PAGE_SIZE
;
625 arg
->len
= (pages
-1)*PAGE_SIZE
;
626 arg
->tail
[0].iov_len
= 0;
630 if (signalled() || kthread_should_stop())
633 /* Normally we will wait up to 5 seconds for any required
634 * cache information to be provided.
636 rqstp
->rq_chandle
.thread_wait
= 5*HZ
;
638 spin_lock_bh(&pool
->sp_lock
);
639 xprt
= svc_xprt_dequeue(pool
);
641 rqstp
->rq_xprt
= xprt
;
643 rqstp
->rq_reserved
= serv
->sv_max_mesg
;
644 atomic_add(rqstp
->rq_reserved
, &xprt
->xpt_reserved
);
646 /* As there is a shortage of threads and this request
647 * had to be queued, don't allow the thread to wait so
648 * long for cache updates.
650 rqstp
->rq_chandle
.thread_wait
= 1*HZ
;
652 /* No data pending. Go to sleep */
653 svc_thread_enqueue(pool
, rqstp
);
656 * We have to be able to interrupt this wait
657 * to bring down the daemons ...
659 set_current_state(TASK_INTERRUPTIBLE
);
662 * checking kthread_should_stop() here allows us to avoid
663 * locking and signalling when stopping kthreads that call
664 * svc_recv. If the thread has already been woken up, then
665 * we can exit here without sleeping. If not, then it
666 * it'll be woken up quickly during the schedule_timeout
668 if (kthread_should_stop()) {
669 set_current_state(TASK_RUNNING
);
670 spin_unlock_bh(&pool
->sp_lock
);
674 add_wait_queue(&rqstp
->rq_wait
, &wait
);
675 spin_unlock_bh(&pool
->sp_lock
);
677 time_left
= schedule_timeout(timeout
);
681 spin_lock_bh(&pool
->sp_lock
);
682 remove_wait_queue(&rqstp
->rq_wait
, &wait
);
684 pool
->sp_stats
.threads_timedout
++;
686 xprt
= rqstp
->rq_xprt
;
688 svc_thread_dequeue(pool
, rqstp
);
689 spin_unlock_bh(&pool
->sp_lock
);
690 dprintk("svc: server %p, no data yet\n", rqstp
);
691 if (signalled() || kthread_should_stop())
697 spin_unlock_bh(&pool
->sp_lock
);
700 if (test_bit(XPT_CLOSE
, &xprt
->xpt_flags
)) {
701 dprintk("svc_recv: found XPT_CLOSE\n");
702 svc_delete_xprt(xprt
);
703 /* Leave XPT_BUSY set on the dead xprt: */
706 if (test_bit(XPT_LISTENER
, &xprt
->xpt_flags
)) {
707 struct svc_xprt
*newxpt
;
708 newxpt
= xprt
->xpt_ops
->xpo_accept(xprt
);
711 * We know this module_get will succeed because the
712 * listener holds a reference too
714 __module_get(newxpt
->xpt_class
->xcl_owner
);
715 svc_check_conn_limits(xprt
->xpt_server
);
716 spin_lock_bh(&serv
->sv_lock
);
717 set_bit(XPT_TEMP
, &newxpt
->xpt_flags
);
718 list_add(&newxpt
->xpt_list
, &serv
->sv_tempsocks
);
720 if (serv
->sv_temptimer
.function
== NULL
) {
721 /* setup timer to age temp transports */
722 setup_timer(&serv
->sv_temptimer
,
724 (unsigned long)serv
);
725 mod_timer(&serv
->sv_temptimer
,
726 jiffies
+ svc_conn_age_period
* HZ
);
728 spin_unlock_bh(&serv
->sv_lock
);
729 svc_xprt_received(newxpt
);
731 } else if (xprt
->xpt_ops
->xpo_has_wspace(xprt
)) {
732 dprintk("svc: server %p, pool %u, transport %p, inuse=%d\n",
733 rqstp
, pool
->sp_id
, xprt
,
734 atomic_read(&xprt
->xpt_ref
.refcount
));
735 rqstp
->rq_deferred
= svc_deferred_dequeue(xprt
);
736 if (rqstp
->rq_deferred
)
737 len
= svc_deferred_recv(rqstp
);
739 len
= xprt
->xpt_ops
->xpo_recvfrom(rqstp
);
740 dprintk("svc: got len=%d\n", len
);
742 svc_xprt_received(xprt
);
744 /* No data, incomplete (TCP) read, or accept() */
745 if (len
== 0 || len
== -EAGAIN
)
748 clear_bit(XPT_OLD
, &xprt
->xpt_flags
);
750 rqstp
->rq_secure
= svc_port_is_privileged(svc_addr(rqstp
));
751 rqstp
->rq_chandle
.defer
= svc_defer
;
754 serv
->sv_stats
->netcnt
++;
757 rqstp
->rq_res
.len
= 0;
758 svc_xprt_release(rqstp
);
761 EXPORT_SYMBOL_GPL(svc_recv
);
766 void svc_drop(struct svc_rqst
*rqstp
)
768 dprintk("svc: xprt %p dropped request\n", rqstp
->rq_xprt
);
769 svc_xprt_release(rqstp
);
771 EXPORT_SYMBOL_GPL(svc_drop
);
774 * Return reply to client.
776 int svc_send(struct svc_rqst
*rqstp
)
778 struct svc_xprt
*xprt
;
782 xprt
= rqstp
->rq_xprt
;
786 /* release the receive skb before sending the reply */
787 rqstp
->rq_xprt
->xpt_ops
->xpo_release_rqst(rqstp
);
789 /* calculate over-all length */
791 xb
->len
= xb
->head
[0].iov_len
+
795 /* Grab mutex to serialize outgoing data. */
796 mutex_lock(&xprt
->xpt_mutex
);
797 if (test_bit(XPT_DEAD
, &xprt
->xpt_flags
))
800 len
= xprt
->xpt_ops
->xpo_sendto(rqstp
);
801 mutex_unlock(&xprt
->xpt_mutex
);
802 rpc_wake_up(&xprt
->xpt_bc_pending
);
803 svc_xprt_release(rqstp
);
805 if (len
== -ECONNREFUSED
|| len
== -ENOTCONN
|| len
== -EAGAIN
)
811 * Timer function to close old temporary transports, using
812 * a mark-and-sweep algorithm.
814 static void svc_age_temp_xprts(unsigned long closure
)
816 struct svc_serv
*serv
= (struct svc_serv
*)closure
;
817 struct svc_xprt
*xprt
;
818 struct list_head
*le
, *next
;
819 LIST_HEAD(to_be_aged
);
821 dprintk("svc_age_temp_xprts\n");
823 if (!spin_trylock_bh(&serv
->sv_lock
)) {
824 /* busy, try again 1 sec later */
825 dprintk("svc_age_temp_xprts: busy\n");
826 mod_timer(&serv
->sv_temptimer
, jiffies
+ HZ
);
830 list_for_each_safe(le
, next
, &serv
->sv_tempsocks
) {
831 xprt
= list_entry(le
, struct svc_xprt
, xpt_list
);
833 /* First time through, just mark it OLD. Second time
834 * through, close it. */
835 if (!test_and_set_bit(XPT_OLD
, &xprt
->xpt_flags
))
837 if (atomic_read(&xprt
->xpt_ref
.refcount
) > 1 ||
838 test_bit(XPT_BUSY
, &xprt
->xpt_flags
))
841 list_move(le
, &to_be_aged
);
842 set_bit(XPT_CLOSE
, &xprt
->xpt_flags
);
843 set_bit(XPT_DETACHED
, &xprt
->xpt_flags
);
845 spin_unlock_bh(&serv
->sv_lock
);
847 while (!list_empty(&to_be_aged
)) {
848 le
= to_be_aged
.next
;
849 /* fiddling the xpt_list node is safe 'cos we're XPT_DETACHED */
851 xprt
= list_entry(le
, struct svc_xprt
, xpt_list
);
853 dprintk("queuing xprt %p for closing\n", xprt
);
855 /* a thread will dequeue and close it soon */
856 svc_xprt_enqueue(xprt
);
860 mod_timer(&serv
->sv_temptimer
, jiffies
+ svc_conn_age_period
* HZ
);
863 static void call_xpt_users(struct svc_xprt
*xprt
)
865 struct svc_xpt_user
*u
;
867 spin_lock(&xprt
->xpt_lock
);
868 while (!list_empty(&xprt
->xpt_users
)) {
869 u
= list_first_entry(&xprt
->xpt_users
, struct svc_xpt_user
, list
);
873 spin_unlock(&xprt
->xpt_lock
);
877 * Remove a dead transport
879 static void svc_delete_xprt(struct svc_xprt
*xprt
)
881 struct svc_serv
*serv
= xprt
->xpt_server
;
882 struct svc_deferred_req
*dr
;
884 /* Only do this once */
885 if (test_and_set_bit(XPT_DEAD
, &xprt
->xpt_flags
))
888 dprintk("svc: svc_delete_xprt(%p)\n", xprt
);
889 xprt
->xpt_ops
->xpo_detach(xprt
);
891 spin_lock_bh(&serv
->sv_lock
);
892 if (!test_and_set_bit(XPT_DETACHED
, &xprt
->xpt_flags
))
893 list_del_init(&xprt
->xpt_list
);
894 BUG_ON(!list_empty(&xprt
->xpt_ready
));
895 if (test_bit(XPT_TEMP
, &xprt
->xpt_flags
))
897 spin_unlock_bh(&serv
->sv_lock
);
899 while ((dr
= svc_deferred_dequeue(xprt
)) != NULL
)
902 call_xpt_users(xprt
);
906 void svc_close_xprt(struct svc_xprt
*xprt
)
908 set_bit(XPT_CLOSE
, &xprt
->xpt_flags
);
909 if (test_and_set_bit(XPT_BUSY
, &xprt
->xpt_flags
))
910 /* someone else will have to effect the close */
913 * We expect svc_close_xprt() to work even when no threads are
914 * running (e.g., while configuring the server before starting
915 * any threads), so if the transport isn't busy, we delete
918 svc_delete_xprt(xprt
);
920 EXPORT_SYMBOL_GPL(svc_close_xprt
);
922 static void svc_close_list(struct list_head
*xprt_list
, struct net
*net
)
924 struct svc_xprt
*xprt
;
926 list_for_each_entry(xprt
, xprt_list
, xpt_list
) {
927 if (xprt
->xpt_net
!= net
)
929 set_bit(XPT_CLOSE
, &xprt
->xpt_flags
);
930 set_bit(XPT_BUSY
, &xprt
->xpt_flags
);
934 static void svc_clear_pools(struct svc_serv
*serv
, struct net
*net
)
936 struct svc_pool
*pool
;
937 struct svc_xprt
*xprt
;
938 struct svc_xprt
*tmp
;
941 for (i
= 0; i
< serv
->sv_nrpools
; i
++) {
942 pool
= &serv
->sv_pools
[i
];
944 spin_lock_bh(&pool
->sp_lock
);
945 list_for_each_entry_safe(xprt
, tmp
, &pool
->sp_sockets
, xpt_ready
) {
946 if (xprt
->xpt_net
!= net
)
948 list_del_init(&xprt
->xpt_ready
);
950 spin_unlock_bh(&pool
->sp_lock
);
954 static void svc_clear_list(struct list_head
*xprt_list
, struct net
*net
)
956 struct svc_xprt
*xprt
;
957 struct svc_xprt
*tmp
;
959 list_for_each_entry_safe(xprt
, tmp
, xprt_list
, xpt_list
) {
960 if (xprt
->xpt_net
!= net
)
962 svc_delete_xprt(xprt
);
964 list_for_each_entry(xprt
, xprt_list
, xpt_list
)
965 BUG_ON(xprt
->xpt_net
== net
);
968 void svc_close_net(struct svc_serv
*serv
, struct net
*net
)
970 svc_close_list(&serv
->sv_tempsocks
, net
);
971 svc_close_list(&serv
->sv_permsocks
, net
);
973 svc_clear_pools(serv
, net
);
975 * At this point the sp_sockets lists will stay empty, since
976 * svc_enqueue will not add new entries without taking the
977 * sp_lock and checking XPT_BUSY.
979 svc_clear_list(&serv
->sv_tempsocks
, net
);
980 svc_clear_list(&serv
->sv_permsocks
, net
);
984 * Handle defer and revisit of requests
987 static void svc_revisit(struct cache_deferred_req
*dreq
, int too_many
)
989 struct svc_deferred_req
*dr
=
990 container_of(dreq
, struct svc_deferred_req
, handle
);
991 struct svc_xprt
*xprt
= dr
->xprt
;
993 spin_lock(&xprt
->xpt_lock
);
994 set_bit(XPT_DEFERRED
, &xprt
->xpt_flags
);
995 if (too_many
|| test_bit(XPT_DEAD
, &xprt
->xpt_flags
)) {
996 spin_unlock(&xprt
->xpt_lock
);
997 dprintk("revisit canceled\n");
1002 dprintk("revisit queued\n");
1004 list_add(&dr
->handle
.recent
, &xprt
->xpt_deferred
);
1005 spin_unlock(&xprt
->xpt_lock
);
1006 svc_xprt_enqueue(xprt
);
1011 * Save the request off for later processing. The request buffer looks
1014 * <xprt-header><rpc-header><rpc-pagelist><rpc-tail>
1016 * This code can only handle requests that consist of an xprt-header
1019 static struct cache_deferred_req
*svc_defer(struct cache_req
*req
)
1021 struct svc_rqst
*rqstp
= container_of(req
, struct svc_rqst
, rq_chandle
);
1022 struct svc_deferred_req
*dr
;
1024 if (rqstp
->rq_arg
.page_len
|| !rqstp
->rq_usedeferral
)
1025 return NULL
; /* if more than a page, give up FIXME */
1026 if (rqstp
->rq_deferred
) {
1027 dr
= rqstp
->rq_deferred
;
1028 rqstp
->rq_deferred
= NULL
;
1032 /* FIXME maybe discard if size too large */
1033 size
= sizeof(struct svc_deferred_req
) + rqstp
->rq_arg
.len
;
1034 dr
= kmalloc(size
, GFP_KERNEL
);
1038 dr
->handle
.owner
= rqstp
->rq_server
;
1039 dr
->prot
= rqstp
->rq_prot
;
1040 memcpy(&dr
->addr
, &rqstp
->rq_addr
, rqstp
->rq_addrlen
);
1041 dr
->addrlen
= rqstp
->rq_addrlen
;
1042 dr
->daddr
= rqstp
->rq_daddr
;
1043 dr
->argslen
= rqstp
->rq_arg
.len
>> 2;
1044 dr
->xprt_hlen
= rqstp
->rq_xprt_hlen
;
1046 /* back up head to the start of the buffer and copy */
1047 skip
= rqstp
->rq_arg
.len
- rqstp
->rq_arg
.head
[0].iov_len
;
1048 memcpy(dr
->args
, rqstp
->rq_arg
.head
[0].iov_base
- skip
,
1051 svc_xprt_get(rqstp
->rq_xprt
);
1052 dr
->xprt
= rqstp
->rq_xprt
;
1053 rqstp
->rq_dropme
= true;
1055 dr
->handle
.revisit
= svc_revisit
;
1060 * recv data from a deferred request into an active one
1062 static int svc_deferred_recv(struct svc_rqst
*rqstp
)
1064 struct svc_deferred_req
*dr
= rqstp
->rq_deferred
;
1066 /* setup iov_base past transport header */
1067 rqstp
->rq_arg
.head
[0].iov_base
= dr
->args
+ (dr
->xprt_hlen
>>2);
1068 /* The iov_len does not include the transport header bytes */
1069 rqstp
->rq_arg
.head
[0].iov_len
= (dr
->argslen
<<2) - dr
->xprt_hlen
;
1070 rqstp
->rq_arg
.page_len
= 0;
1071 /* The rq_arg.len includes the transport header bytes */
1072 rqstp
->rq_arg
.len
= dr
->argslen
<<2;
1073 rqstp
->rq_prot
= dr
->prot
;
1074 memcpy(&rqstp
->rq_addr
, &dr
->addr
, dr
->addrlen
);
1075 rqstp
->rq_addrlen
= dr
->addrlen
;
1076 /* Save off transport header len in case we get deferred again */
1077 rqstp
->rq_xprt_hlen
= dr
->xprt_hlen
;
1078 rqstp
->rq_daddr
= dr
->daddr
;
1079 rqstp
->rq_respages
= rqstp
->rq_pages
;
1080 return (dr
->argslen
<<2) - dr
->xprt_hlen
;
1084 static struct svc_deferred_req
*svc_deferred_dequeue(struct svc_xprt
*xprt
)
1086 struct svc_deferred_req
*dr
= NULL
;
1088 if (!test_bit(XPT_DEFERRED
, &xprt
->xpt_flags
))
1090 spin_lock(&xprt
->xpt_lock
);
1091 if (!list_empty(&xprt
->xpt_deferred
)) {
1092 dr
= list_entry(xprt
->xpt_deferred
.next
,
1093 struct svc_deferred_req
,
1095 list_del_init(&dr
->handle
.recent
);
1097 clear_bit(XPT_DEFERRED
, &xprt
->xpt_flags
);
1098 spin_unlock(&xprt
->xpt_lock
);
1103 * svc_find_xprt - find an RPC transport instance
1104 * @serv: pointer to svc_serv to search
1105 * @xcl_name: C string containing transport's class name
1106 * @net: owner net pointer
1107 * @af: Address family of transport's local address
1108 * @port: transport's IP port number
1110 * Return the transport instance pointer for the endpoint accepting
1111 * connections/peer traffic from the specified transport class,
1112 * address family and port.
1114 * Specifying 0 for the address family or port is effectively a
1115 * wild-card, and will result in matching the first transport in the
1116 * service's list that has a matching class name.
1118 struct svc_xprt
*svc_find_xprt(struct svc_serv
*serv
, const char *xcl_name
,
1119 struct net
*net
, const sa_family_t af
,
1120 const unsigned short port
)
1122 struct svc_xprt
*xprt
;
1123 struct svc_xprt
*found
= NULL
;
1125 /* Sanity check the args */
1126 if (serv
== NULL
|| xcl_name
== NULL
)
1129 spin_lock_bh(&serv
->sv_lock
);
1130 list_for_each_entry(xprt
, &serv
->sv_permsocks
, xpt_list
) {
1131 if (xprt
->xpt_net
!= net
)
1133 if (strcmp(xprt
->xpt_class
->xcl_name
, xcl_name
))
1135 if (af
!= AF_UNSPEC
&& af
!= xprt
->xpt_local
.ss_family
)
1137 if (port
!= 0 && port
!= svc_xprt_local_port(xprt
))
1143 spin_unlock_bh(&serv
->sv_lock
);
1146 EXPORT_SYMBOL_GPL(svc_find_xprt
);
1148 static int svc_one_xprt_name(const struct svc_xprt
*xprt
,
1149 char *pos
, int remaining
)
1153 len
= snprintf(pos
, remaining
, "%s %u\n",
1154 xprt
->xpt_class
->xcl_name
,
1155 svc_xprt_local_port(xprt
));
1156 if (len
>= remaining
)
1157 return -ENAMETOOLONG
;
1162 * svc_xprt_names - format a buffer with a list of transport names
1163 * @serv: pointer to an RPC service
1164 * @buf: pointer to a buffer to be filled in
1165 * @buflen: length of buffer to be filled in
1167 * Fills in @buf with a string containing a list of transport names,
1168 * each name terminated with '\n'.
1170 * Returns positive length of the filled-in string on success; otherwise
1171 * a negative errno value is returned if an error occurs.
1173 int svc_xprt_names(struct svc_serv
*serv
, char *buf
, const int buflen
)
1175 struct svc_xprt
*xprt
;
1179 /* Sanity check args */
1183 spin_lock_bh(&serv
->sv_lock
);
1187 list_for_each_entry(xprt
, &serv
->sv_permsocks
, xpt_list
) {
1188 len
= svc_one_xprt_name(xprt
, pos
, buflen
- totlen
);
1200 spin_unlock_bh(&serv
->sv_lock
);
1203 EXPORT_SYMBOL_GPL(svc_xprt_names
);
1206 /*----------------------------------------------------------------------------*/
1208 static void *svc_pool_stats_start(struct seq_file
*m
, loff_t
*pos
)
1210 unsigned int pidx
= (unsigned int)*pos
;
1211 struct svc_serv
*serv
= m
->private;
1213 dprintk("svc_pool_stats_start, *pidx=%u\n", pidx
);
1216 return SEQ_START_TOKEN
;
1217 return (pidx
> serv
->sv_nrpools
? NULL
: &serv
->sv_pools
[pidx
-1]);
1220 static void *svc_pool_stats_next(struct seq_file
*m
, void *p
, loff_t
*pos
)
1222 struct svc_pool
*pool
= p
;
1223 struct svc_serv
*serv
= m
->private;
1225 dprintk("svc_pool_stats_next, *pos=%llu\n", *pos
);
1227 if (p
== SEQ_START_TOKEN
) {
1228 pool
= &serv
->sv_pools
[0];
1230 unsigned int pidx
= (pool
- &serv
->sv_pools
[0]);
1231 if (pidx
< serv
->sv_nrpools
-1)
1232 pool
= &serv
->sv_pools
[pidx
+1];
1240 static void svc_pool_stats_stop(struct seq_file
*m
, void *p
)
1244 static int svc_pool_stats_show(struct seq_file
*m
, void *p
)
1246 struct svc_pool
*pool
= p
;
1248 if (p
== SEQ_START_TOKEN
) {
1249 seq_puts(m
, "# pool packets-arrived sockets-enqueued threads-woken threads-timedout\n");
1253 seq_printf(m
, "%u %lu %lu %lu %lu\n",
1255 pool
->sp_stats
.packets
,
1256 pool
->sp_stats
.sockets_queued
,
1257 pool
->sp_stats
.threads_woken
,
1258 pool
->sp_stats
.threads_timedout
);
1263 static const struct seq_operations svc_pool_stats_seq_ops
= {
1264 .start
= svc_pool_stats_start
,
1265 .next
= svc_pool_stats_next
,
1266 .stop
= svc_pool_stats_stop
,
1267 .show
= svc_pool_stats_show
,
1270 int svc_pool_stats_open(struct svc_serv
*serv
, struct file
*file
)
1274 err
= seq_open(file
, &svc_pool_stats_seq_ops
);
1276 ((struct seq_file
*) file
->private_data
)->private = serv
;
1279 EXPORT_SYMBOL(svc_pool_stats_open
);
1281 /*----------------------------------------------------------------------------*/