1 // SPDX-License-Identifier: GPL-2.0-only
3 * linux/net/sunrpc/svc_xprt.c
5 * Author: Tom Tucker <tom@opengridcomputing.com>
8 #include <linux/sched.h>
9 #include <linux/errno.h>
10 #include <linux/freezer.h>
11 #include <linux/kthread.h>
12 #include <linux/slab.h>
14 #include <linux/sunrpc/addr.h>
15 #include <linux/sunrpc/stats.h>
16 #include <linux/sunrpc/svc_xprt.h>
17 #include <linux/sunrpc/svcsock.h>
18 #include <linux/sunrpc/xprt.h>
19 #include <linux/module.h>
20 #include <linux/netdevice.h>
21 #include <trace/events/sunrpc.h>
23 #define RPCDBG_FACILITY RPCDBG_SVCXPRT
25 static unsigned int svc_rpc_per_connection_limit __read_mostly
;
26 module_param(svc_rpc_per_connection_limit
, uint
, 0644);
29 static struct svc_deferred_req
*svc_deferred_dequeue(struct svc_xprt
*xprt
);
30 static int svc_deferred_recv(struct svc_rqst
*rqstp
);
31 static struct cache_deferred_req
*svc_defer(struct cache_req
*req
);
32 static void svc_age_temp_xprts(struct timer_list
*t
);
33 static void svc_delete_xprt(struct svc_xprt
*xprt
);
35 /* apparently the "standard" is that clients close
36 * idle connections after 5 minutes, servers after
38 * http://nfsv4bat.org/Documents/ConnectAThon/1996/nfstcp.pdf
40 static int svc_conn_age_period
= 6*60;
42 /* List of registered transport classes */
43 static DEFINE_SPINLOCK(svc_xprt_class_lock
);
44 static LIST_HEAD(svc_xprt_class_list
);
46 /* SMP locking strategy:
48 * svc_pool->sp_lock protects most of the fields of that pool.
49 * svc_serv->sv_lock protects sv_tempsocks, sv_permsocks, sv_tmpcnt.
50 * when both need to be taken (rare), svc_serv->sv_lock is first.
51 * The "service mutex" protects svc_serv->sv_nrthread.
52 * svc_sock->sk_lock protects the svc_sock->sk_deferred list
53 * and the ->sk_info_authunix cache.
55 * The XPT_BUSY bit in xprt->xpt_flags prevents a transport being
56 * enqueued multiply. During normal transport processing this bit
57 * is set by svc_xprt_enqueue and cleared by svc_xprt_received.
58 * Providers should not manipulate this bit directly.
60 * Some flags can be set to certain values at any time
61 * providing that certain rules are followed:
64 * - Can be set or cleared at any time.
65 * - After a set, svc_xprt_enqueue must be called to enqueue
66 * the transport for processing.
67 * - After a clear, the transport must be read/accepted.
68 * If this succeeds, it must be set again.
70 * - Can set at any time. It is never cleared.
72 * - Can only be set while XPT_BUSY is held which ensures
73 * that no other thread will be using the transport or will
74 * try to set XPT_DEAD.
76 int svc_reg_xprt_class(struct svc_xprt_class
*xcl
)
78 struct svc_xprt_class
*cl
;
81 dprintk("svc: Adding svc transport class '%s'\n", xcl
->xcl_name
);
83 INIT_LIST_HEAD(&xcl
->xcl_list
);
84 spin_lock(&svc_xprt_class_lock
);
85 /* Make sure there isn't already a class with the same name */
86 list_for_each_entry(cl
, &svc_xprt_class_list
, xcl_list
) {
87 if (strcmp(xcl
->xcl_name
, cl
->xcl_name
) == 0)
90 list_add_tail(&xcl
->xcl_list
, &svc_xprt_class_list
);
93 spin_unlock(&svc_xprt_class_lock
);
96 EXPORT_SYMBOL_GPL(svc_reg_xprt_class
);
98 void svc_unreg_xprt_class(struct svc_xprt_class
*xcl
)
100 dprintk("svc: Removing svc transport class '%s'\n", xcl
->xcl_name
);
101 spin_lock(&svc_xprt_class_lock
);
102 list_del_init(&xcl
->xcl_list
);
103 spin_unlock(&svc_xprt_class_lock
);
105 EXPORT_SYMBOL_GPL(svc_unreg_xprt_class
);
108 * svc_print_xprts - Format the transport list for printing
109 * @buf: target buffer for formatted address
110 * @maxlen: length of target buffer
112 * Fills in @buf with a string containing a list of transport names, each name
113 * terminated with '\n'. If the buffer is too small, some entries may be
114 * missing, but it is guaranteed that all lines in the output buffer are
117 * Returns positive length of the filled-in string.
119 int svc_print_xprts(char *buf
, int maxlen
)
121 struct svc_xprt_class
*xcl
;
126 spin_lock(&svc_xprt_class_lock
);
127 list_for_each_entry(xcl
, &svc_xprt_class_list
, xcl_list
) {
130 slen
= snprintf(tmpstr
, sizeof(tmpstr
), "%s %d\n",
131 xcl
->xcl_name
, xcl
->xcl_max_payload
);
132 if (slen
>= sizeof(tmpstr
) || len
+ slen
>= maxlen
)
137 spin_unlock(&svc_xprt_class_lock
);
142 static void svc_xprt_free(struct kref
*kref
)
144 struct svc_xprt
*xprt
=
145 container_of(kref
, struct svc_xprt
, xpt_ref
);
146 struct module
*owner
= xprt
->xpt_class
->xcl_owner
;
147 if (test_bit(XPT_CACHE_AUTH
, &xprt
->xpt_flags
))
148 svcauth_unix_info_release(xprt
);
149 put_cred(xprt
->xpt_cred
);
150 put_net(xprt
->xpt_net
);
151 /* See comment on corresponding get in xs_setup_bc_tcp(): */
152 if (xprt
->xpt_bc_xprt
)
153 xprt_put(xprt
->xpt_bc_xprt
);
154 if (xprt
->xpt_bc_xps
)
155 xprt_switch_put(xprt
->xpt_bc_xps
);
156 trace_svc_xprt_free(xprt
);
157 xprt
->xpt_ops
->xpo_free(xprt
);
161 void svc_xprt_put(struct svc_xprt
*xprt
)
163 kref_put(&xprt
->xpt_ref
, svc_xprt_free
);
165 EXPORT_SYMBOL_GPL(svc_xprt_put
);
168 * Called by transport drivers to initialize the transport independent
169 * portion of the transport instance.
171 void svc_xprt_init(struct net
*net
, struct svc_xprt_class
*xcl
,
172 struct svc_xprt
*xprt
, struct svc_serv
*serv
)
174 memset(xprt
, 0, sizeof(*xprt
));
175 xprt
->xpt_class
= xcl
;
176 xprt
->xpt_ops
= xcl
->xcl_ops
;
177 kref_init(&xprt
->xpt_ref
);
178 xprt
->xpt_server
= serv
;
179 INIT_LIST_HEAD(&xprt
->xpt_list
);
180 INIT_LIST_HEAD(&xprt
->xpt_ready
);
181 INIT_LIST_HEAD(&xprt
->xpt_deferred
);
182 INIT_LIST_HEAD(&xprt
->xpt_users
);
183 mutex_init(&xprt
->xpt_mutex
);
184 spin_lock_init(&xprt
->xpt_lock
);
185 set_bit(XPT_BUSY
, &xprt
->xpt_flags
);
186 xprt
->xpt_net
= get_net(net
);
187 strcpy(xprt
->xpt_remotebuf
, "uninitialized");
189 EXPORT_SYMBOL_GPL(svc_xprt_init
);
191 static struct svc_xprt
*__svc_xpo_create(struct svc_xprt_class
*xcl
,
192 struct svc_serv
*serv
,
195 const unsigned short port
,
198 struct sockaddr_in sin
= {
199 .sin_family
= AF_INET
,
200 .sin_addr
.s_addr
= htonl(INADDR_ANY
),
201 .sin_port
= htons(port
),
203 #if IS_ENABLED(CONFIG_IPV6)
204 struct sockaddr_in6 sin6
= {
205 .sin6_family
= AF_INET6
,
206 .sin6_addr
= IN6ADDR_ANY_INIT
,
207 .sin6_port
= htons(port
),
210 struct svc_xprt
*xprt
;
211 struct sockaddr
*sap
;
216 sap
= (struct sockaddr
*)&sin
;
219 #if IS_ENABLED(CONFIG_IPV6)
221 sap
= (struct sockaddr
*)&sin6
;
226 return ERR_PTR(-EAFNOSUPPORT
);
229 xprt
= xcl
->xcl_ops
->xpo_create(serv
, net
, sap
, len
, flags
);
231 trace_svc_xprt_create_err(serv
->sv_program
->pg_name
,
232 xcl
->xcl_name
, sap
, xprt
);
237 * svc_xprt_received conditionally queues the transport for processing
238 * by another thread. The caller must hold the XPT_BUSY bit and must
239 * not thereafter touch transport data.
241 * Note: XPT_DATA only gets cleared when a read-attempt finds no (or
242 * insufficient) data.
244 static void svc_xprt_received(struct svc_xprt
*xprt
)
246 if (!test_bit(XPT_BUSY
, &xprt
->xpt_flags
)) {
247 WARN_ONCE(1, "xprt=0x%p already busy!", xprt
);
251 /* As soon as we clear busy, the xprt could be closed and
252 * 'put', so we need a reference to call svc_enqueue_xprt with:
255 smp_mb__before_atomic();
256 clear_bit(XPT_BUSY
, &xprt
->xpt_flags
);
257 xprt
->xpt_server
->sv_ops
->svo_enqueue_xprt(xprt
);
261 void svc_add_new_perm_xprt(struct svc_serv
*serv
, struct svc_xprt
*new)
263 clear_bit(XPT_TEMP
, &new->xpt_flags
);
264 spin_lock_bh(&serv
->sv_lock
);
265 list_add(&new->xpt_list
, &serv
->sv_permsocks
);
266 spin_unlock_bh(&serv
->sv_lock
);
267 svc_xprt_received(new);
270 static int _svc_create_xprt(struct svc_serv
*serv
, const char *xprt_name
,
271 struct net
*net
, const int family
,
272 const unsigned short port
, int flags
,
273 const struct cred
*cred
)
275 struct svc_xprt_class
*xcl
;
277 spin_lock(&svc_xprt_class_lock
);
278 list_for_each_entry(xcl
, &svc_xprt_class_list
, xcl_list
) {
279 struct svc_xprt
*newxprt
;
280 unsigned short newport
;
282 if (strcmp(xprt_name
, xcl
->xcl_name
))
285 if (!try_module_get(xcl
->xcl_owner
))
288 spin_unlock(&svc_xprt_class_lock
);
289 newxprt
= __svc_xpo_create(xcl
, serv
, net
, family
, port
, flags
);
290 if (IS_ERR(newxprt
)) {
291 module_put(xcl
->xcl_owner
);
292 return PTR_ERR(newxprt
);
294 newxprt
->xpt_cred
= get_cred(cred
);
295 svc_add_new_perm_xprt(serv
, newxprt
);
296 newport
= svc_xprt_local_port(newxprt
);
300 spin_unlock(&svc_xprt_class_lock
);
301 /* This errno is exposed to user space. Provide a reasonable
302 * perror msg for a bad transport. */
303 return -EPROTONOSUPPORT
;
306 int svc_create_xprt(struct svc_serv
*serv
, const char *xprt_name
,
307 struct net
*net
, const int family
,
308 const unsigned short port
, int flags
,
309 const struct cred
*cred
)
313 err
= _svc_create_xprt(serv
, xprt_name
, net
, family
, port
, flags
, cred
);
314 if (err
== -EPROTONOSUPPORT
) {
315 request_module("svc%s", xprt_name
);
316 err
= _svc_create_xprt(serv
, xprt_name
, net
, family
, port
, flags
, cred
);
320 EXPORT_SYMBOL_GPL(svc_create_xprt
);
323 * Copy the local and remote xprt addresses to the rqstp structure
325 void svc_xprt_copy_addrs(struct svc_rqst
*rqstp
, struct svc_xprt
*xprt
)
327 memcpy(&rqstp
->rq_addr
, &xprt
->xpt_remote
, xprt
->xpt_remotelen
);
328 rqstp
->rq_addrlen
= xprt
->xpt_remotelen
;
331 * Destination address in request is needed for binding the
332 * source address in RPC replies/callbacks later.
334 memcpy(&rqstp
->rq_daddr
, &xprt
->xpt_local
, xprt
->xpt_locallen
);
335 rqstp
->rq_daddrlen
= xprt
->xpt_locallen
;
337 EXPORT_SYMBOL_GPL(svc_xprt_copy_addrs
);
340 * svc_print_addr - Format rq_addr field for printing
341 * @rqstp: svc_rqst struct containing address to print
342 * @buf: target buffer for formatted address
343 * @len: length of target buffer
346 char *svc_print_addr(struct svc_rqst
*rqstp
, char *buf
, size_t len
)
348 return __svc_print_addr(svc_addr(rqstp
), buf
, len
);
350 EXPORT_SYMBOL_GPL(svc_print_addr
);
352 static bool svc_xprt_slots_in_range(struct svc_xprt
*xprt
)
354 unsigned int limit
= svc_rpc_per_connection_limit
;
355 int nrqsts
= atomic_read(&xprt
->xpt_nr_rqsts
);
357 return limit
== 0 || (nrqsts
>= 0 && nrqsts
< limit
);
360 static bool svc_xprt_reserve_slot(struct svc_rqst
*rqstp
, struct svc_xprt
*xprt
)
362 if (!test_bit(RQ_DATA
, &rqstp
->rq_flags
)) {
363 if (!svc_xprt_slots_in_range(xprt
))
365 atomic_inc(&xprt
->xpt_nr_rqsts
);
366 set_bit(RQ_DATA
, &rqstp
->rq_flags
);
371 static void svc_xprt_release_slot(struct svc_rqst
*rqstp
)
373 struct svc_xprt
*xprt
= rqstp
->rq_xprt
;
374 if (test_and_clear_bit(RQ_DATA
, &rqstp
->rq_flags
)) {
375 atomic_dec(&xprt
->xpt_nr_rqsts
);
376 smp_wmb(); /* See smp_rmb() in svc_xprt_ready() */
377 svc_xprt_enqueue(xprt
);
381 static bool svc_xprt_ready(struct svc_xprt
*xprt
)
383 unsigned long xpt_flags
;
386 * If another cpu has recently updated xpt_flags,
387 * sk_sock->flags, xpt_reserved, or xpt_nr_rqsts, we need to
388 * know about it; otherwise it's possible that both that cpu and
389 * this one could call svc_xprt_enqueue() without either
390 * svc_xprt_enqueue() recognizing that the conditions below
391 * are satisfied, and we could stall indefinitely:
394 xpt_flags
= READ_ONCE(xprt
->xpt_flags
);
396 if (xpt_flags
& (BIT(XPT_CONN
) | BIT(XPT_CLOSE
)))
398 if (xpt_flags
& (BIT(XPT_DATA
) | BIT(XPT_DEFERRED
))) {
399 if (xprt
->xpt_ops
->xpo_has_wspace(xprt
) &&
400 svc_xprt_slots_in_range(xprt
))
402 trace_svc_xprt_no_write_space(xprt
);
408 void svc_xprt_do_enqueue(struct svc_xprt
*xprt
)
410 struct svc_pool
*pool
;
411 struct svc_rqst
*rqstp
= NULL
;
414 if (!svc_xprt_ready(xprt
))
417 /* Mark transport as busy. It will remain in this state until
418 * the provider calls svc_xprt_received. We update XPT_BUSY
419 * atomically because it also guards against trying to enqueue
420 * the transport twice.
422 if (test_and_set_bit(XPT_BUSY
, &xprt
->xpt_flags
))
426 pool
= svc_pool_for_cpu(xprt
->xpt_server
, cpu
);
428 atomic_long_inc(&pool
->sp_stats
.packets
);
430 spin_lock_bh(&pool
->sp_lock
);
431 list_add_tail(&xprt
->xpt_ready
, &pool
->sp_sockets
);
432 pool
->sp_stats
.sockets_queued
++;
433 spin_unlock_bh(&pool
->sp_lock
);
435 /* find a thread for this xprt */
437 list_for_each_entry_rcu(rqstp
, &pool
->sp_all_threads
, rq_all
) {
438 if (test_and_set_bit(RQ_BUSY
, &rqstp
->rq_flags
))
440 atomic_long_inc(&pool
->sp_stats
.threads_woken
);
441 rqstp
->rq_qtime
= ktime_get();
442 wake_up_process(rqstp
->rq_task
);
445 set_bit(SP_CONGESTED
, &pool
->sp_flags
);
450 trace_svc_xprt_do_enqueue(xprt
, rqstp
);
452 EXPORT_SYMBOL_GPL(svc_xprt_do_enqueue
);
455 * Queue up a transport with data pending. If there are idle nfsd
456 * processes, wake 'em up.
459 void svc_xprt_enqueue(struct svc_xprt
*xprt
)
461 if (test_bit(XPT_BUSY
, &xprt
->xpt_flags
))
463 xprt
->xpt_server
->sv_ops
->svo_enqueue_xprt(xprt
);
465 EXPORT_SYMBOL_GPL(svc_xprt_enqueue
);
468 * Dequeue the first transport, if there is one.
470 static struct svc_xprt
*svc_xprt_dequeue(struct svc_pool
*pool
)
472 struct svc_xprt
*xprt
= NULL
;
474 if (list_empty(&pool
->sp_sockets
))
477 spin_lock_bh(&pool
->sp_lock
);
478 if (likely(!list_empty(&pool
->sp_sockets
))) {
479 xprt
= list_first_entry(&pool
->sp_sockets
,
480 struct svc_xprt
, xpt_ready
);
481 list_del_init(&xprt
->xpt_ready
);
484 spin_unlock_bh(&pool
->sp_lock
);
490 * svc_reserve - change the space reserved for the reply to a request.
491 * @rqstp: The request in question
492 * @space: new max space to reserve
494 * Each request reserves some space on the output queue of the transport
495 * to make sure the reply fits. This function reduces that reserved
496 * space to be the amount of space used already, plus @space.
499 void svc_reserve(struct svc_rqst
*rqstp
, int space
)
501 struct svc_xprt
*xprt
= rqstp
->rq_xprt
;
503 space
+= rqstp
->rq_res
.head
[0].iov_len
;
505 if (xprt
&& space
< rqstp
->rq_reserved
) {
506 atomic_sub((rqstp
->rq_reserved
- space
), &xprt
->xpt_reserved
);
507 rqstp
->rq_reserved
= space
;
508 smp_wmb(); /* See smp_rmb() in svc_xprt_ready() */
509 svc_xprt_enqueue(xprt
);
512 EXPORT_SYMBOL_GPL(svc_reserve
);
514 static void svc_xprt_release(struct svc_rqst
*rqstp
)
516 struct svc_xprt
*xprt
= rqstp
->rq_xprt
;
518 xprt
->xpt_ops
->xpo_release_rqst(rqstp
);
520 kfree(rqstp
->rq_deferred
);
521 rqstp
->rq_deferred
= NULL
;
523 svc_free_res_pages(rqstp
);
524 rqstp
->rq_res
.page_len
= 0;
525 rqstp
->rq_res
.page_base
= 0;
527 /* Reset response buffer and release
529 * But first, check that enough space was reserved
530 * for the reply, otherwise we have a bug!
532 if ((rqstp
->rq_res
.len
) > rqstp
->rq_reserved
)
533 printk(KERN_ERR
"RPC request reserved %d but used %d\n",
537 rqstp
->rq_res
.head
[0].iov_len
= 0;
538 svc_reserve(rqstp
, 0);
539 svc_xprt_release_slot(rqstp
);
540 rqstp
->rq_xprt
= NULL
;
545 * Some svc_serv's will have occasional work to do, even when a xprt is not
546 * waiting to be serviced. This function is there to "kick" a task in one of
547 * those services so that it can wake up and do that work. Note that we only
548 * bother with pool 0 as we don't need to wake up more than one thread for
551 void svc_wake_up(struct svc_serv
*serv
)
553 struct svc_rqst
*rqstp
;
554 struct svc_pool
*pool
;
556 pool
= &serv
->sv_pools
[0];
559 list_for_each_entry_rcu(rqstp
, &pool
->sp_all_threads
, rq_all
) {
560 /* skip any that aren't queued */
561 if (test_bit(RQ_BUSY
, &rqstp
->rq_flags
))
564 wake_up_process(rqstp
->rq_task
);
565 trace_svc_wake_up(rqstp
->rq_task
->pid
);
570 /* No free entries available */
571 set_bit(SP_TASK_PENDING
, &pool
->sp_flags
);
573 trace_svc_wake_up(0);
575 EXPORT_SYMBOL_GPL(svc_wake_up
);
577 int svc_port_is_privileged(struct sockaddr
*sin
)
579 switch (sin
->sa_family
) {
581 return ntohs(((struct sockaddr_in
*)sin
)->sin_port
)
584 return ntohs(((struct sockaddr_in6
*)sin
)->sin6_port
)
592 * Make sure that we don't have too many active connections. If we have,
593 * something must be dropped. It's not clear what will happen if we allow
594 * "too many" connections, but when dealing with network-facing software,
595 * we have to code defensively. Here we do that by imposing hard limits.
597 * There's no point in trying to do random drop here for DoS
598 * prevention. The NFS clients does 1 reconnect in 15 seconds. An
599 * attacker can easily beat that.
601 * The only somewhat efficient mechanism would be if drop old
602 * connections from the same IP first. But right now we don't even
603 * record the client IP in svc_sock.
605 * single-threaded services that expect a lot of clients will probably
606 * need to set sv_maxconn to override the default value which is based
607 * on the number of threads
609 static void svc_check_conn_limits(struct svc_serv
*serv
)
611 unsigned int limit
= serv
->sv_maxconn
? serv
->sv_maxconn
:
612 (serv
->sv_nrthreads
+3) * 20;
614 if (serv
->sv_tmpcnt
> limit
) {
615 struct svc_xprt
*xprt
= NULL
;
616 spin_lock_bh(&serv
->sv_lock
);
617 if (!list_empty(&serv
->sv_tempsocks
)) {
618 /* Try to help the admin */
619 net_notice_ratelimited("%s: too many open connections, consider increasing the %s\n",
620 serv
->sv_name
, serv
->sv_maxconn
?
621 "max number of connections" :
622 "number of threads");
624 * Always select the oldest connection. It's not fair,
627 xprt
= list_entry(serv
->sv_tempsocks
.prev
,
630 set_bit(XPT_CLOSE
, &xprt
->xpt_flags
);
633 spin_unlock_bh(&serv
->sv_lock
);
636 svc_xprt_enqueue(xprt
);
642 static int svc_alloc_arg(struct svc_rqst
*rqstp
)
644 struct svc_serv
*serv
= rqstp
->rq_server
;
649 /* now allocate needed pages. If we get a failure, sleep briefly */
650 pages
= (serv
->sv_max_mesg
+ 2 * PAGE_SIZE
) >> PAGE_SHIFT
;
651 if (pages
> RPCSVC_MAXPAGES
) {
652 pr_warn_once("svc: warning: pages=%u > RPCSVC_MAXPAGES=%lu\n",
653 pages
, RPCSVC_MAXPAGES
);
654 /* use as many pages as possible */
655 pages
= RPCSVC_MAXPAGES
;
657 for (i
= 0; i
< pages
; i
++)
658 while (rqstp
->rq_pages
[i
] == NULL
) {
659 struct page
*p
= alloc_page(GFP_KERNEL
);
661 set_current_state(TASK_INTERRUPTIBLE
);
662 if (signalled() || kthread_should_stop()) {
663 set_current_state(TASK_RUNNING
);
666 schedule_timeout(msecs_to_jiffies(500));
668 rqstp
->rq_pages
[i
] = p
;
670 rqstp
->rq_page_end
= &rqstp
->rq_pages
[i
];
671 rqstp
->rq_pages
[i
++] = NULL
; /* this might be seen in nfs_read_actor */
673 /* Make arg->head point to first page and arg->pages point to rest */
674 arg
= &rqstp
->rq_arg
;
675 arg
->head
[0].iov_base
= page_address(rqstp
->rq_pages
[0]);
676 arg
->head
[0].iov_len
= PAGE_SIZE
;
677 arg
->pages
= rqstp
->rq_pages
+ 1;
679 /* save at least one page for response */
680 arg
->page_len
= (pages
-2)*PAGE_SIZE
;
681 arg
->len
= (pages
-1)*PAGE_SIZE
;
682 arg
->tail
[0].iov_len
= 0;
687 rqst_should_sleep(struct svc_rqst
*rqstp
)
689 struct svc_pool
*pool
= rqstp
->rq_pool
;
691 /* did someone call svc_wake_up? */
692 if (test_and_clear_bit(SP_TASK_PENDING
, &pool
->sp_flags
))
695 /* was a socket queued? */
696 if (!list_empty(&pool
->sp_sockets
))
699 /* are we shutting down? */
700 if (signalled() || kthread_should_stop())
703 /* are we freezing? */
704 if (freezing(current
))
710 static struct svc_xprt
*svc_get_next_xprt(struct svc_rqst
*rqstp
, long timeout
)
712 struct svc_pool
*pool
= rqstp
->rq_pool
;
715 /* rq_xprt should be clear on entry */
716 WARN_ON_ONCE(rqstp
->rq_xprt
);
718 rqstp
->rq_xprt
= svc_xprt_dequeue(pool
);
723 * We have to be able to interrupt this wait
724 * to bring down the daemons ...
726 set_current_state(TASK_INTERRUPTIBLE
);
727 smp_mb__before_atomic();
728 clear_bit(SP_CONGESTED
, &pool
->sp_flags
);
729 clear_bit(RQ_BUSY
, &rqstp
->rq_flags
);
730 smp_mb__after_atomic();
732 if (likely(rqst_should_sleep(rqstp
)))
733 time_left
= schedule_timeout(timeout
);
735 __set_current_state(TASK_RUNNING
);
739 set_bit(RQ_BUSY
, &rqstp
->rq_flags
);
740 smp_mb__after_atomic();
741 rqstp
->rq_xprt
= svc_xprt_dequeue(pool
);
746 atomic_long_inc(&pool
->sp_stats
.threads_timedout
);
748 if (signalled() || kthread_should_stop())
749 return ERR_PTR(-EINTR
);
750 return ERR_PTR(-EAGAIN
);
752 /* Normally we will wait up to 5 seconds for any required
753 * cache information to be provided.
755 if (!test_bit(SP_CONGESTED
, &pool
->sp_flags
))
756 rqstp
->rq_chandle
.thread_wait
= 5*HZ
;
758 rqstp
->rq_chandle
.thread_wait
= 1*HZ
;
759 trace_svc_xprt_dequeue(rqstp
);
760 return rqstp
->rq_xprt
;
763 static void svc_add_new_temp_xprt(struct svc_serv
*serv
, struct svc_xprt
*newxpt
)
765 spin_lock_bh(&serv
->sv_lock
);
766 set_bit(XPT_TEMP
, &newxpt
->xpt_flags
);
767 list_add(&newxpt
->xpt_list
, &serv
->sv_tempsocks
);
769 if (serv
->sv_temptimer
.function
== NULL
) {
770 /* setup timer to age temp transports */
771 serv
->sv_temptimer
.function
= svc_age_temp_xprts
;
772 mod_timer(&serv
->sv_temptimer
,
773 jiffies
+ svc_conn_age_period
* HZ
);
775 spin_unlock_bh(&serv
->sv_lock
);
776 svc_xprt_received(newxpt
);
779 static int svc_handle_xprt(struct svc_rqst
*rqstp
, struct svc_xprt
*xprt
)
781 struct svc_serv
*serv
= rqstp
->rq_server
;
784 if (test_bit(XPT_CLOSE
, &xprt
->xpt_flags
)) {
785 if (test_and_clear_bit(XPT_KILL_TEMP
, &xprt
->xpt_flags
))
786 xprt
->xpt_ops
->xpo_kill_temp_xprt(xprt
);
787 svc_delete_xprt(xprt
);
788 /* Leave XPT_BUSY set on the dead xprt: */
791 if (test_bit(XPT_LISTENER
, &xprt
->xpt_flags
)) {
792 struct svc_xprt
*newxpt
;
794 * We know this module_get will succeed because the
795 * listener holds a reference too
797 __module_get(xprt
->xpt_class
->xcl_owner
);
798 svc_check_conn_limits(xprt
->xpt_server
);
799 newxpt
= xprt
->xpt_ops
->xpo_accept(xprt
);
801 newxpt
->xpt_cred
= get_cred(xprt
->xpt_cred
);
802 svc_add_new_temp_xprt(serv
, newxpt
);
803 trace_svc_xprt_accept(newxpt
, serv
->sv_name
);
805 module_put(xprt
->xpt_class
->xcl_owner
);
806 } else if (svc_xprt_reserve_slot(rqstp
, xprt
)) {
807 /* XPT_DATA|XPT_DEFERRED case: */
808 dprintk("svc: server %p, pool %u, transport %p, inuse=%d\n",
809 rqstp
, rqstp
->rq_pool
->sp_id
, xprt
,
810 kref_read(&xprt
->xpt_ref
));
811 rqstp
->rq_deferred
= svc_deferred_dequeue(xprt
);
812 if (rqstp
->rq_deferred
)
813 len
= svc_deferred_recv(rqstp
);
815 len
= xprt
->xpt_ops
->xpo_recvfrom(rqstp
);
816 rqstp
->rq_stime
= ktime_get();
817 rqstp
->rq_reserved
= serv
->sv_max_mesg
;
818 atomic_add(rqstp
->rq_reserved
, &xprt
->xpt_reserved
);
820 /* clear XPT_BUSY: */
821 svc_xprt_received(xprt
);
823 trace_svc_handle_xprt(xprt
, len
);
828 * Receive the next request on any transport. This code is carefully
829 * organised not to touch any cachelines in the shared svc_serv
830 * structure, only cachelines in the local svc_pool.
832 int svc_recv(struct svc_rqst
*rqstp
, long timeout
)
834 struct svc_xprt
*xprt
= NULL
;
835 struct svc_serv
*serv
= rqstp
->rq_server
;
838 err
= svc_alloc_arg(rqstp
);
845 if (signalled() || kthread_should_stop())
848 xprt
= svc_get_next_xprt(rqstp
, timeout
);
854 len
= svc_handle_xprt(rqstp
, xprt
);
856 /* No data, incomplete (TCP) read, or accept() */
861 clear_bit(XPT_OLD
, &xprt
->xpt_flags
);
863 xprt
->xpt_ops
->xpo_secure_port(rqstp
);
864 rqstp
->rq_chandle
.defer
= svc_defer
;
865 rqstp
->rq_xid
= svc_getu32(&rqstp
->rq_arg
.head
[0]);
868 serv
->sv_stats
->netcnt
++;
869 trace_svc_xdr_recvfrom(rqstp
, &rqstp
->rq_arg
);
872 rqstp
->rq_res
.len
= 0;
873 svc_xprt_release(rqstp
);
877 EXPORT_SYMBOL_GPL(svc_recv
);
882 void svc_drop(struct svc_rqst
*rqstp
)
884 trace_svc_drop(rqstp
);
885 svc_xprt_release(rqstp
);
887 EXPORT_SYMBOL_GPL(svc_drop
);
890 * Return reply to client.
892 int svc_send(struct svc_rqst
*rqstp
)
894 struct svc_xprt
*xprt
;
898 xprt
= rqstp
->rq_xprt
;
902 /* calculate over-all length */
904 xb
->len
= xb
->head
[0].iov_len
+
907 trace_svc_xdr_sendto(rqstp
, xb
);
908 trace_svc_stats_latency(rqstp
);
910 len
= xprt
->xpt_ops
->xpo_sendto(rqstp
);
912 trace_svc_send(rqstp
, len
);
913 svc_xprt_release(rqstp
);
915 if (len
== -ECONNREFUSED
|| len
== -ENOTCONN
|| len
== -EAGAIN
)
922 * Timer function to close old temporary transports, using
923 * a mark-and-sweep algorithm.
925 static void svc_age_temp_xprts(struct timer_list
*t
)
927 struct svc_serv
*serv
= from_timer(serv
, t
, sv_temptimer
);
928 struct svc_xprt
*xprt
;
929 struct list_head
*le
, *next
;
931 dprintk("svc_age_temp_xprts\n");
933 if (!spin_trylock_bh(&serv
->sv_lock
)) {
934 /* busy, try again 1 sec later */
935 dprintk("svc_age_temp_xprts: busy\n");
936 mod_timer(&serv
->sv_temptimer
, jiffies
+ HZ
);
940 list_for_each_safe(le
, next
, &serv
->sv_tempsocks
) {
941 xprt
= list_entry(le
, struct svc_xprt
, xpt_list
);
943 /* First time through, just mark it OLD. Second time
944 * through, close it. */
945 if (!test_and_set_bit(XPT_OLD
, &xprt
->xpt_flags
))
947 if (kref_read(&xprt
->xpt_ref
) > 1 ||
948 test_bit(XPT_BUSY
, &xprt
->xpt_flags
))
951 set_bit(XPT_CLOSE
, &xprt
->xpt_flags
);
952 dprintk("queuing xprt %p for closing\n", xprt
);
954 /* a thread will dequeue and close it soon */
955 svc_xprt_enqueue(xprt
);
957 spin_unlock_bh(&serv
->sv_lock
);
959 mod_timer(&serv
->sv_temptimer
, jiffies
+ svc_conn_age_period
* HZ
);
962 /* Close temporary transports whose xpt_local matches server_addr immediately
963 * instead of waiting for them to be picked up by the timer.
965 * This is meant to be called from a notifier_block that runs when an ip
966 * address is deleted.
968 void svc_age_temp_xprts_now(struct svc_serv
*serv
, struct sockaddr
*server_addr
)
970 struct svc_xprt
*xprt
;
971 struct list_head
*le
, *next
;
972 LIST_HEAD(to_be_closed
);
974 spin_lock_bh(&serv
->sv_lock
);
975 list_for_each_safe(le
, next
, &serv
->sv_tempsocks
) {
976 xprt
= list_entry(le
, struct svc_xprt
, xpt_list
);
977 if (rpc_cmp_addr(server_addr
, (struct sockaddr
*)
979 dprintk("svc_age_temp_xprts_now: found %p\n", xprt
);
980 list_move(le
, &to_be_closed
);
983 spin_unlock_bh(&serv
->sv_lock
);
985 while (!list_empty(&to_be_closed
)) {
986 le
= to_be_closed
.next
;
988 xprt
= list_entry(le
, struct svc_xprt
, xpt_list
);
989 set_bit(XPT_CLOSE
, &xprt
->xpt_flags
);
990 set_bit(XPT_KILL_TEMP
, &xprt
->xpt_flags
);
991 dprintk("svc_age_temp_xprts_now: queuing xprt %p for closing\n",
993 svc_xprt_enqueue(xprt
);
996 EXPORT_SYMBOL_GPL(svc_age_temp_xprts_now
);
998 static void call_xpt_users(struct svc_xprt
*xprt
)
1000 struct svc_xpt_user
*u
;
1002 spin_lock(&xprt
->xpt_lock
);
1003 while (!list_empty(&xprt
->xpt_users
)) {
1004 u
= list_first_entry(&xprt
->xpt_users
, struct svc_xpt_user
, list
);
1005 list_del_init(&u
->list
);
1008 spin_unlock(&xprt
->xpt_lock
);
1012 * Remove a dead transport
1014 static void svc_delete_xprt(struct svc_xprt
*xprt
)
1016 struct svc_serv
*serv
= xprt
->xpt_server
;
1017 struct svc_deferred_req
*dr
;
1019 if (test_and_set_bit(XPT_DEAD
, &xprt
->xpt_flags
))
1022 trace_svc_xprt_detach(xprt
);
1023 xprt
->xpt_ops
->xpo_detach(xprt
);
1024 if (xprt
->xpt_bc_xprt
)
1025 xprt
->xpt_bc_xprt
->ops
->close(xprt
->xpt_bc_xprt
);
1027 spin_lock_bh(&serv
->sv_lock
);
1028 list_del_init(&xprt
->xpt_list
);
1029 WARN_ON_ONCE(!list_empty(&xprt
->xpt_ready
));
1030 if (test_bit(XPT_TEMP
, &xprt
->xpt_flags
))
1032 spin_unlock_bh(&serv
->sv_lock
);
1034 while ((dr
= svc_deferred_dequeue(xprt
)) != NULL
)
1037 call_xpt_users(xprt
);
1041 void svc_close_xprt(struct svc_xprt
*xprt
)
1043 trace_svc_xprt_close(xprt
);
1044 set_bit(XPT_CLOSE
, &xprt
->xpt_flags
);
1045 if (test_and_set_bit(XPT_BUSY
, &xprt
->xpt_flags
))
1046 /* someone else will have to effect the close */
1049 * We expect svc_close_xprt() to work even when no threads are
1050 * running (e.g., while configuring the server before starting
1051 * any threads), so if the transport isn't busy, we delete
1054 svc_delete_xprt(xprt
);
1056 EXPORT_SYMBOL_GPL(svc_close_xprt
);
1058 static int svc_close_list(struct svc_serv
*serv
, struct list_head
*xprt_list
, struct net
*net
)
1060 struct svc_xprt
*xprt
;
1063 spin_lock(&serv
->sv_lock
);
1064 list_for_each_entry(xprt
, xprt_list
, xpt_list
) {
1065 if (xprt
->xpt_net
!= net
)
1068 set_bit(XPT_CLOSE
, &xprt
->xpt_flags
);
1069 svc_xprt_enqueue(xprt
);
1071 spin_unlock(&serv
->sv_lock
);
1075 static struct svc_xprt
*svc_dequeue_net(struct svc_serv
*serv
, struct net
*net
)
1077 struct svc_pool
*pool
;
1078 struct svc_xprt
*xprt
;
1079 struct svc_xprt
*tmp
;
1082 for (i
= 0; i
< serv
->sv_nrpools
; i
++) {
1083 pool
= &serv
->sv_pools
[i
];
1085 spin_lock_bh(&pool
->sp_lock
);
1086 list_for_each_entry_safe(xprt
, tmp
, &pool
->sp_sockets
, xpt_ready
) {
1087 if (xprt
->xpt_net
!= net
)
1089 list_del_init(&xprt
->xpt_ready
);
1090 spin_unlock_bh(&pool
->sp_lock
);
1093 spin_unlock_bh(&pool
->sp_lock
);
1098 static void svc_clean_up_xprts(struct svc_serv
*serv
, struct net
*net
)
1100 struct svc_xprt
*xprt
;
1102 while ((xprt
= svc_dequeue_net(serv
, net
))) {
1103 set_bit(XPT_CLOSE
, &xprt
->xpt_flags
);
1104 svc_delete_xprt(xprt
);
1109 * Server threads may still be running (especially in the case where the
1110 * service is still running in other network namespaces).
1112 * So we shut down sockets the same way we would on a running server, by
1113 * setting XPT_CLOSE, enqueuing, and letting a thread pick it up to do
1114 * the close. In the case there are no such other threads,
1115 * threads running, svc_clean_up_xprts() does a simple version of a
1116 * server's main event loop, and in the case where there are other
1117 * threads, we may need to wait a little while and then check again to
1118 * see if they're done.
1120 void svc_close_net(struct svc_serv
*serv
, struct net
*net
)
1124 while (svc_close_list(serv
, &serv
->sv_permsocks
, net
) +
1125 svc_close_list(serv
, &serv
->sv_tempsocks
, net
)) {
1127 svc_clean_up_xprts(serv
, net
);
1133 * Handle defer and revisit of requests
1136 static void svc_revisit(struct cache_deferred_req
*dreq
, int too_many
)
1138 struct svc_deferred_req
*dr
=
1139 container_of(dreq
, struct svc_deferred_req
, handle
);
1140 struct svc_xprt
*xprt
= dr
->xprt
;
1142 spin_lock(&xprt
->xpt_lock
);
1143 set_bit(XPT_DEFERRED
, &xprt
->xpt_flags
);
1144 if (too_many
|| test_bit(XPT_DEAD
, &xprt
->xpt_flags
)) {
1145 spin_unlock(&xprt
->xpt_lock
);
1146 trace_svc_defer_drop(dr
);
1152 list_add(&dr
->handle
.recent
, &xprt
->xpt_deferred
);
1153 spin_unlock(&xprt
->xpt_lock
);
1154 trace_svc_defer_queue(dr
);
1155 svc_xprt_enqueue(xprt
);
1160 * Save the request off for later processing. The request buffer looks
1163 * <xprt-header><rpc-header><rpc-pagelist><rpc-tail>
1165 * This code can only handle requests that consist of an xprt-header
1168 static struct cache_deferred_req
*svc_defer(struct cache_req
*req
)
1170 struct svc_rqst
*rqstp
= container_of(req
, struct svc_rqst
, rq_chandle
);
1171 struct svc_deferred_req
*dr
;
1173 if (rqstp
->rq_arg
.page_len
|| !test_bit(RQ_USEDEFERRAL
, &rqstp
->rq_flags
))
1174 return NULL
; /* if more than a page, give up FIXME */
1175 if (rqstp
->rq_deferred
) {
1176 dr
= rqstp
->rq_deferred
;
1177 rqstp
->rq_deferred
= NULL
;
1181 /* FIXME maybe discard if size too large */
1182 size
= sizeof(struct svc_deferred_req
) + rqstp
->rq_arg
.len
;
1183 dr
= kmalloc(size
, GFP_KERNEL
);
1187 dr
->handle
.owner
= rqstp
->rq_server
;
1188 dr
->prot
= rqstp
->rq_prot
;
1189 memcpy(&dr
->addr
, &rqstp
->rq_addr
, rqstp
->rq_addrlen
);
1190 dr
->addrlen
= rqstp
->rq_addrlen
;
1191 dr
->daddr
= rqstp
->rq_daddr
;
1192 dr
->argslen
= rqstp
->rq_arg
.len
>> 2;
1193 dr
->xprt_hlen
= rqstp
->rq_xprt_hlen
;
1195 /* back up head to the start of the buffer and copy */
1196 skip
= rqstp
->rq_arg
.len
- rqstp
->rq_arg
.head
[0].iov_len
;
1197 memcpy(dr
->args
, rqstp
->rq_arg
.head
[0].iov_base
- skip
,
1200 trace_svc_defer(rqstp
);
1201 svc_xprt_get(rqstp
->rq_xprt
);
1202 dr
->xprt
= rqstp
->rq_xprt
;
1203 set_bit(RQ_DROPME
, &rqstp
->rq_flags
);
1205 dr
->handle
.revisit
= svc_revisit
;
1210 * recv data from a deferred request into an active one
1212 static noinline
int svc_deferred_recv(struct svc_rqst
*rqstp
)
1214 struct svc_deferred_req
*dr
= rqstp
->rq_deferred
;
1216 trace_svc_defer_recv(dr
);
1218 /* setup iov_base past transport header */
1219 rqstp
->rq_arg
.head
[0].iov_base
= dr
->args
+ (dr
->xprt_hlen
>>2);
1220 /* The iov_len does not include the transport header bytes */
1221 rqstp
->rq_arg
.head
[0].iov_len
= (dr
->argslen
<<2) - dr
->xprt_hlen
;
1222 rqstp
->rq_arg
.page_len
= 0;
1223 /* The rq_arg.len includes the transport header bytes */
1224 rqstp
->rq_arg
.len
= dr
->argslen
<<2;
1225 rqstp
->rq_prot
= dr
->prot
;
1226 memcpy(&rqstp
->rq_addr
, &dr
->addr
, dr
->addrlen
);
1227 rqstp
->rq_addrlen
= dr
->addrlen
;
1228 /* Save off transport header len in case we get deferred again */
1229 rqstp
->rq_xprt_hlen
= dr
->xprt_hlen
;
1230 rqstp
->rq_daddr
= dr
->daddr
;
1231 rqstp
->rq_respages
= rqstp
->rq_pages
;
1232 return (dr
->argslen
<<2) - dr
->xprt_hlen
;
1236 static struct svc_deferred_req
*svc_deferred_dequeue(struct svc_xprt
*xprt
)
1238 struct svc_deferred_req
*dr
= NULL
;
1240 if (!test_bit(XPT_DEFERRED
, &xprt
->xpt_flags
))
1242 spin_lock(&xprt
->xpt_lock
);
1243 if (!list_empty(&xprt
->xpt_deferred
)) {
1244 dr
= list_entry(xprt
->xpt_deferred
.next
,
1245 struct svc_deferred_req
,
1247 list_del_init(&dr
->handle
.recent
);
1249 clear_bit(XPT_DEFERRED
, &xprt
->xpt_flags
);
1250 spin_unlock(&xprt
->xpt_lock
);
1255 * svc_find_xprt - find an RPC transport instance
1256 * @serv: pointer to svc_serv to search
1257 * @xcl_name: C string containing transport's class name
1258 * @net: owner net pointer
1259 * @af: Address family of transport's local address
1260 * @port: transport's IP port number
1262 * Return the transport instance pointer for the endpoint accepting
1263 * connections/peer traffic from the specified transport class,
1264 * address family and port.
1266 * Specifying 0 for the address family or port is effectively a
1267 * wild-card, and will result in matching the first transport in the
1268 * service's list that has a matching class name.
1270 struct svc_xprt
*svc_find_xprt(struct svc_serv
*serv
, const char *xcl_name
,
1271 struct net
*net
, const sa_family_t af
,
1272 const unsigned short port
)
1274 struct svc_xprt
*xprt
;
1275 struct svc_xprt
*found
= NULL
;
1277 /* Sanity check the args */
1278 if (serv
== NULL
|| xcl_name
== NULL
)
1281 spin_lock_bh(&serv
->sv_lock
);
1282 list_for_each_entry(xprt
, &serv
->sv_permsocks
, xpt_list
) {
1283 if (xprt
->xpt_net
!= net
)
1285 if (strcmp(xprt
->xpt_class
->xcl_name
, xcl_name
))
1287 if (af
!= AF_UNSPEC
&& af
!= xprt
->xpt_local
.ss_family
)
1289 if (port
!= 0 && port
!= svc_xprt_local_port(xprt
))
1295 spin_unlock_bh(&serv
->sv_lock
);
1298 EXPORT_SYMBOL_GPL(svc_find_xprt
);
1300 static int svc_one_xprt_name(const struct svc_xprt
*xprt
,
1301 char *pos
, int remaining
)
1305 len
= snprintf(pos
, remaining
, "%s %u\n",
1306 xprt
->xpt_class
->xcl_name
,
1307 svc_xprt_local_port(xprt
));
1308 if (len
>= remaining
)
1309 return -ENAMETOOLONG
;
1314 * svc_xprt_names - format a buffer with a list of transport names
1315 * @serv: pointer to an RPC service
1316 * @buf: pointer to a buffer to be filled in
1317 * @buflen: length of buffer to be filled in
1319 * Fills in @buf with a string containing a list of transport names,
1320 * each name terminated with '\n'.
1322 * Returns positive length of the filled-in string on success; otherwise
1323 * a negative errno value is returned if an error occurs.
1325 int svc_xprt_names(struct svc_serv
*serv
, char *buf
, const int buflen
)
1327 struct svc_xprt
*xprt
;
1331 /* Sanity check args */
1335 spin_lock_bh(&serv
->sv_lock
);
1339 list_for_each_entry(xprt
, &serv
->sv_permsocks
, xpt_list
) {
1340 len
= svc_one_xprt_name(xprt
, pos
, buflen
- totlen
);
1352 spin_unlock_bh(&serv
->sv_lock
);
1355 EXPORT_SYMBOL_GPL(svc_xprt_names
);
1358 /*----------------------------------------------------------------------------*/
1360 static void *svc_pool_stats_start(struct seq_file
*m
, loff_t
*pos
)
1362 unsigned int pidx
= (unsigned int)*pos
;
1363 struct svc_serv
*serv
= m
->private;
1365 dprintk("svc_pool_stats_start, *pidx=%u\n", pidx
);
1368 return SEQ_START_TOKEN
;
1369 return (pidx
> serv
->sv_nrpools
? NULL
: &serv
->sv_pools
[pidx
-1]);
1372 static void *svc_pool_stats_next(struct seq_file
*m
, void *p
, loff_t
*pos
)
1374 struct svc_pool
*pool
= p
;
1375 struct svc_serv
*serv
= m
->private;
1377 dprintk("svc_pool_stats_next, *pos=%llu\n", *pos
);
1379 if (p
== SEQ_START_TOKEN
) {
1380 pool
= &serv
->sv_pools
[0];
1382 unsigned int pidx
= (pool
- &serv
->sv_pools
[0]);
1383 if (pidx
< serv
->sv_nrpools
-1)
1384 pool
= &serv
->sv_pools
[pidx
+1];
1392 static void svc_pool_stats_stop(struct seq_file
*m
, void *p
)
1396 static int svc_pool_stats_show(struct seq_file
*m
, void *p
)
1398 struct svc_pool
*pool
= p
;
1400 if (p
== SEQ_START_TOKEN
) {
1401 seq_puts(m
, "# pool packets-arrived sockets-enqueued threads-woken threads-timedout\n");
1405 seq_printf(m
, "%u %lu %lu %lu %lu\n",
1407 (unsigned long)atomic_long_read(&pool
->sp_stats
.packets
),
1408 pool
->sp_stats
.sockets_queued
,
1409 (unsigned long)atomic_long_read(&pool
->sp_stats
.threads_woken
),
1410 (unsigned long)atomic_long_read(&pool
->sp_stats
.threads_timedout
));
1415 static const struct seq_operations svc_pool_stats_seq_ops
= {
1416 .start
= svc_pool_stats_start
,
1417 .next
= svc_pool_stats_next
,
1418 .stop
= svc_pool_stats_stop
,
1419 .show
= svc_pool_stats_show
,
1422 int svc_pool_stats_open(struct svc_serv
*serv
, struct file
*file
)
1426 err
= seq_open(file
, &svc_pool_stats_seq_ops
);
1428 ((struct seq_file
*) file
->private_data
)->private = serv
;
1431 EXPORT_SYMBOL(svc_pool_stats_open
);
1433 /*----------------------------------------------------------------------------*/