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TOMOYO Linux Cross Reference
Linux/net/sunrpc/svc.c

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  1 /*
  2  * linux/net/sunrpc/svc.c
  3  *
  4  * High-level RPC service routines
  5  *
  6  * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
  7  *
  8  * Multiple threads pools and NUMAisation
  9  * Copyright (c) 2006 Silicon Graphics, Inc.
 10  * by Greg Banks <gnb@melbourne.sgi.com>
 11  */
 12 
 13 #include <linux/linkage.h>
 14 #include <linux/sched.h>
 15 #include <linux/errno.h>
 16 #include <linux/net.h>
 17 #include <linux/in.h>
 18 #include <linux/mm.h>
 19 #include <linux/interrupt.h>
 20 #include <linux/module.h>
 21 #include <linux/kthread.h>
 22 #include <linux/slab.h>
 23 #include <linux/nsproxy.h>
 24 
 25 #include <linux/sunrpc/types.h>
 26 #include <linux/sunrpc/xdr.h>
 27 #include <linux/sunrpc/stats.h>
 28 #include <linux/sunrpc/svcsock.h>
 29 #include <linux/sunrpc/clnt.h>
 30 #include <linux/sunrpc/bc_xprt.h>
 31 
 32 #define RPCDBG_FACILITY RPCDBG_SVCDSP
 33 
 34 static void svc_unregister(const struct svc_serv *serv, struct net *net);
 35 
 36 #define svc_serv_is_pooled(serv)    ((serv)->sv_function)
 37 
 38 /*
 39  * Mode for mapping cpus to pools.
 40  */
 41 enum {
 42         SVC_POOL_AUTO = -1,     /* choose one of the others */
 43         SVC_POOL_GLOBAL,        /* no mapping, just a single global pool
 44                                  * (legacy & UP mode) */
 45         SVC_POOL_PERCPU,        /* one pool per cpu */
 46         SVC_POOL_PERNODE        /* one pool per numa node */
 47 };
 48 #define SVC_POOL_DEFAULT        SVC_POOL_GLOBAL
 49 
 50 /*
 51  * Structure for mapping cpus to pools and vice versa.
 52  * Setup once during sunrpc initialisation.
 53  */
 54 static struct svc_pool_map {
 55         int count;                      /* How many svc_servs use us */
 56         int mode;                       /* Note: int not enum to avoid
 57                                          * warnings about "enumeration value
 58                                          * not handled in switch" */
 59         unsigned int npools;
 60         unsigned int *pool_to;          /* maps pool id to cpu or node */
 61         unsigned int *to_pool;          /* maps cpu or node to pool id */
 62 } svc_pool_map = {
 63         .count = 0,
 64         .mode = SVC_POOL_DEFAULT
 65 };
 66 static DEFINE_MUTEX(svc_pool_map_mutex);/* protects svc_pool_map.count only */
 67 
 68 static int
 69 param_set_pool_mode(const char *val, struct kernel_param *kp)
 70 {
 71         int *ip = (int *)kp->arg;
 72         struct svc_pool_map *m = &svc_pool_map;
 73         int err;
 74 
 75         mutex_lock(&svc_pool_map_mutex);
 76 
 77         err = -EBUSY;
 78         if (m->count)
 79                 goto out;
 80 
 81         err = 0;
 82         if (!strncmp(val, "auto", 4))
 83                 *ip = SVC_POOL_AUTO;
 84         else if (!strncmp(val, "global", 6))
 85                 *ip = SVC_POOL_GLOBAL;
 86         else if (!strncmp(val, "percpu", 6))
 87                 *ip = SVC_POOL_PERCPU;
 88         else if (!strncmp(val, "pernode", 7))
 89                 *ip = SVC_POOL_PERNODE;
 90         else
 91                 err = -EINVAL;
 92 
 93 out:
 94         mutex_unlock(&svc_pool_map_mutex);
 95         return err;
 96 }
 97 
 98 static int
 99 param_get_pool_mode(char *buf, struct kernel_param *kp)
100 {
101         int *ip = (int *)kp->arg;
102 
103         switch (*ip)
104         {
105         case SVC_POOL_AUTO:
106                 return strlcpy(buf, "auto", 20);
107         case SVC_POOL_GLOBAL:
108                 return strlcpy(buf, "global", 20);
109         case SVC_POOL_PERCPU:
110                 return strlcpy(buf, "percpu", 20);
111         case SVC_POOL_PERNODE:
112                 return strlcpy(buf, "pernode", 20);
113         default:
114                 return sprintf(buf, "%d", *ip);
115         }
116 }
117 
118 module_param_call(pool_mode, param_set_pool_mode, param_get_pool_mode,
119                  &svc_pool_map.mode, 0644);
120 
121 /*
122  * Detect best pool mapping mode heuristically,
123  * according to the machine's topology.
124  */
125 static int
126 svc_pool_map_choose_mode(void)
127 {
128         unsigned int node;
129 
130         if (nr_online_nodes > 1) {
131                 /*
132                  * Actually have multiple NUMA nodes,
133                  * so split pools on NUMA node boundaries
134                  */
135                 return SVC_POOL_PERNODE;
136         }
137 
138         node = first_online_node;
139         if (nr_cpus_node(node) > 2) {
140                 /*
141                  * Non-trivial SMP, or CONFIG_NUMA on
142                  * non-NUMA hardware, e.g. with a generic
143                  * x86_64 kernel on Xeons.  In this case we
144                  * want to divide the pools on cpu boundaries.
145                  */
146                 return SVC_POOL_PERCPU;
147         }
148 
149         /* default: one global pool */
150         return SVC_POOL_GLOBAL;
151 }
152 
153 /*
154  * Allocate the to_pool[] and pool_to[] arrays.
155  * Returns 0 on success or an errno.
156  */
157 static int
158 svc_pool_map_alloc_arrays(struct svc_pool_map *m, unsigned int maxpools)
159 {
160         m->to_pool = kcalloc(maxpools, sizeof(unsigned int), GFP_KERNEL);
161         if (!m->to_pool)
162                 goto fail;
163         m->pool_to = kcalloc(maxpools, sizeof(unsigned int), GFP_KERNEL);
164         if (!m->pool_to)
165                 goto fail_free;
166 
167         return 0;
168 
169 fail_free:
170         kfree(m->to_pool);
171         m->to_pool = NULL;
172 fail:
173         return -ENOMEM;
174 }
175 
176 /*
177  * Initialise the pool map for SVC_POOL_PERCPU mode.
178  * Returns number of pools or <0 on error.
179  */
180 static int
181 svc_pool_map_init_percpu(struct svc_pool_map *m)
182 {
183         unsigned int maxpools = nr_cpu_ids;
184         unsigned int pidx = 0;
185         unsigned int cpu;
186         int err;
187 
188         err = svc_pool_map_alloc_arrays(m, maxpools);
189         if (err)
190                 return err;
191 
192         for_each_online_cpu(cpu) {
193                 BUG_ON(pidx > maxpools);
194                 m->to_pool[cpu] = pidx;
195                 m->pool_to[pidx] = cpu;
196                 pidx++;
197         }
198         /* cpus brought online later all get mapped to pool0, sorry */
199 
200         return pidx;
201 };
202 
203 
204 /*
205  * Initialise the pool map for SVC_POOL_PERNODE mode.
206  * Returns number of pools or <0 on error.
207  */
208 static int
209 svc_pool_map_init_pernode(struct svc_pool_map *m)
210 {
211         unsigned int maxpools = nr_node_ids;
212         unsigned int pidx = 0;
213         unsigned int node;
214         int err;
215 
216         err = svc_pool_map_alloc_arrays(m, maxpools);
217         if (err)
218                 return err;
219 
220         for_each_node_with_cpus(node) {
221                 /* some architectures (e.g. SN2) have cpuless nodes */
222                 BUG_ON(pidx > maxpools);
223                 m->to_pool[node] = pidx;
224                 m->pool_to[pidx] = node;
225                 pidx++;
226         }
227         /* nodes brought online later all get mapped to pool0, sorry */
228 
229         return pidx;
230 }
231 
232 
233 /*
234  * Add a reference to the global map of cpus to pools (and
235  * vice versa).  Initialise the map if we're the first user.
236  * Returns the number of pools.
237  */
238 static unsigned int
239 svc_pool_map_get(void)
240 {
241         struct svc_pool_map *m = &svc_pool_map;
242         int npools = -1;
243 
244         mutex_lock(&svc_pool_map_mutex);
245 
246         if (m->count++) {
247                 mutex_unlock(&svc_pool_map_mutex);
248                 return m->npools;
249         }
250 
251         if (m->mode == SVC_POOL_AUTO)
252                 m->mode = svc_pool_map_choose_mode();
253 
254         switch (m->mode) {
255         case SVC_POOL_PERCPU:
256                 npools = svc_pool_map_init_percpu(m);
257                 break;
258         case SVC_POOL_PERNODE:
259                 npools = svc_pool_map_init_pernode(m);
260                 break;
261         }
262 
263         if (npools < 0) {
264                 /* default, or memory allocation failure */
265                 npools = 1;
266                 m->mode = SVC_POOL_GLOBAL;
267         }
268         m->npools = npools;
269 
270         mutex_unlock(&svc_pool_map_mutex);
271         return m->npools;
272 }
273 
274 
275 /*
276  * Drop a reference to the global map of cpus to pools.
277  * When the last reference is dropped, the map data is
278  * freed; this allows the sysadmin to change the pool
279  * mode using the pool_mode module option without
280  * rebooting or re-loading sunrpc.ko.
281  */
282 static void
283 svc_pool_map_put(void)
284 {
285         struct svc_pool_map *m = &svc_pool_map;
286 
287         mutex_lock(&svc_pool_map_mutex);
288 
289         if (!--m->count) {
290                 kfree(m->to_pool);
291                 m->to_pool = NULL;
292                 kfree(m->pool_to);
293                 m->pool_to = NULL;
294                 m->npools = 0;
295         }
296 
297         mutex_unlock(&svc_pool_map_mutex);
298 }
299 
300 
301 static int svc_pool_map_get_node(unsigned int pidx)
302 {
303         const struct svc_pool_map *m = &svc_pool_map;
304 
305         if (m->count) {
306                 if (m->mode == SVC_POOL_PERCPU)
307                         return cpu_to_node(m->pool_to[pidx]);
308                 if (m->mode == SVC_POOL_PERNODE)
309                         return m->pool_to[pidx];
310         }
311         return NUMA_NO_NODE;
312 }
313 /*
314  * Set the given thread's cpus_allowed mask so that it
315  * will only run on cpus in the given pool.
316  */
317 static inline void
318 svc_pool_map_set_cpumask(struct task_struct *task, unsigned int pidx)
319 {
320         struct svc_pool_map *m = &svc_pool_map;
321         unsigned int node = m->pool_to[pidx];
322 
323         /*
324          * The caller checks for sv_nrpools > 1, which
325          * implies that we've been initialized.
326          */
327         BUG_ON(m->count == 0);
328 
329         switch (m->mode) {
330         case SVC_POOL_PERCPU:
331         {
332                 set_cpus_allowed_ptr(task, cpumask_of(node));
333                 break;
334         }
335         case SVC_POOL_PERNODE:
336         {
337                 set_cpus_allowed_ptr(task, cpumask_of_node(node));
338                 break;
339         }
340         }
341 }
342 
343 /*
344  * Use the mapping mode to choose a pool for a given CPU.
345  * Used when enqueueing an incoming RPC.  Always returns
346  * a non-NULL pool pointer.
347  */
348 struct svc_pool *
349 svc_pool_for_cpu(struct svc_serv *serv, int cpu)
350 {
351         struct svc_pool_map *m = &svc_pool_map;
352         unsigned int pidx = 0;
353 
354         /*
355          * An uninitialised map happens in a pure client when
356          * lockd is brought up, so silently treat it the
357          * same as SVC_POOL_GLOBAL.
358          */
359         if (svc_serv_is_pooled(serv)) {
360                 switch (m->mode) {
361                 case SVC_POOL_PERCPU:
362                         pidx = m->to_pool[cpu];
363                         break;
364                 case SVC_POOL_PERNODE:
365                         pidx = m->to_pool[cpu_to_node(cpu)];
366                         break;
367                 }
368         }
369         return &serv->sv_pools[pidx % serv->sv_nrpools];
370 }
371 
372 int svc_rpcb_setup(struct svc_serv *serv, struct net *net)
373 {
374         int err;
375 
376         err = rpcb_create_local(net);
377         if (err)
378                 return err;
379 
380         /* Remove any stale portmap registrations */
381         svc_unregister(serv, net);
382         return 0;
383 }
384 EXPORT_SYMBOL_GPL(svc_rpcb_setup);
385 
386 void svc_rpcb_cleanup(struct svc_serv *serv, struct net *net)
387 {
388         svc_unregister(serv, net);
389         rpcb_put_local(net);
390 }
391 EXPORT_SYMBOL_GPL(svc_rpcb_cleanup);
392 
393 static int svc_uses_rpcbind(struct svc_serv *serv)
394 {
395         struct svc_program      *progp;
396         unsigned int            i;
397 
398         for (progp = serv->sv_program; progp; progp = progp->pg_next) {
399                 for (i = 0; i < progp->pg_nvers; i++) {
400                         if (progp->pg_vers[i] == NULL)
401                                 continue;
402                         if (progp->pg_vers[i]->vs_hidden == 0)
403                                 return 1;
404                 }
405         }
406 
407         return 0;
408 }
409 
410 int svc_bind(struct svc_serv *serv, struct net *net)
411 {
412         if (!svc_uses_rpcbind(serv))
413                 return 0;
414         return svc_rpcb_setup(serv, net);
415 }
416 EXPORT_SYMBOL_GPL(svc_bind);
417 
418 /*
419  * Create an RPC service
420  */
421 static struct svc_serv *
422 __svc_create(struct svc_program *prog, unsigned int bufsize, int npools,
423              void (*shutdown)(struct svc_serv *serv, struct net *net))
424 {
425         struct svc_serv *serv;
426         unsigned int vers;
427         unsigned int xdrsize;
428         unsigned int i;
429 
430         if (!(serv = kzalloc(sizeof(*serv), GFP_KERNEL)))
431                 return NULL;
432         serv->sv_name      = prog->pg_name;
433         serv->sv_program   = prog;
434         serv->sv_nrthreads = 1;
435         serv->sv_stats     = prog->pg_stats;
436         if (bufsize > RPCSVC_MAXPAYLOAD)
437                 bufsize = RPCSVC_MAXPAYLOAD;
438         serv->sv_max_payload = bufsize? bufsize : 4096;
439         serv->sv_max_mesg  = roundup(serv->sv_max_payload + PAGE_SIZE, PAGE_SIZE);
440         serv->sv_shutdown  = shutdown;
441         xdrsize = 0;
442         while (prog) {
443                 prog->pg_lovers = prog->pg_nvers-1;
444                 for (vers=0; vers<prog->pg_nvers ; vers++)
445                         if (prog->pg_vers[vers]) {
446                                 prog->pg_hivers = vers;
447                                 if (prog->pg_lovers > vers)
448                                         prog->pg_lovers = vers;
449                                 if (prog->pg_vers[vers]->vs_xdrsize > xdrsize)
450                                         xdrsize = prog->pg_vers[vers]->vs_xdrsize;
451                         }
452                 prog = prog->pg_next;
453         }
454         serv->sv_xdrsize   = xdrsize;
455         INIT_LIST_HEAD(&serv->sv_tempsocks);
456         INIT_LIST_HEAD(&serv->sv_permsocks);
457         init_timer(&serv->sv_temptimer);
458         spin_lock_init(&serv->sv_lock);
459 
460         serv->sv_nrpools = npools;
461         serv->sv_pools =
462                 kcalloc(serv->sv_nrpools, sizeof(struct svc_pool),
463                         GFP_KERNEL);
464         if (!serv->sv_pools) {
465                 kfree(serv);
466                 return NULL;
467         }
468 
469         for (i = 0; i < serv->sv_nrpools; i++) {
470                 struct svc_pool *pool = &serv->sv_pools[i];
471 
472                 dprintk("svc: initialising pool %u for %s\n",
473                                 i, serv->sv_name);
474 
475                 pool->sp_id = i;
476                 INIT_LIST_HEAD(&pool->sp_threads);
477                 INIT_LIST_HEAD(&pool->sp_sockets);
478                 INIT_LIST_HEAD(&pool->sp_all_threads);
479                 spin_lock_init(&pool->sp_lock);
480         }
481 
482         if (svc_uses_rpcbind(serv) && (!serv->sv_shutdown))
483                 serv->sv_shutdown = svc_rpcb_cleanup;
484 
485         return serv;
486 }
487 
488 struct svc_serv *
489 svc_create(struct svc_program *prog, unsigned int bufsize,
490            void (*shutdown)(struct svc_serv *serv, struct net *net))
491 {
492         return __svc_create(prog, bufsize, /*npools*/1, shutdown);
493 }
494 EXPORT_SYMBOL_GPL(svc_create);
495 
496 struct svc_serv *
497 svc_create_pooled(struct svc_program *prog, unsigned int bufsize,
498                   void (*shutdown)(struct svc_serv *serv, struct net *net),
499                   svc_thread_fn func, struct module *mod)
500 {
501         struct svc_serv *serv;
502         unsigned int npools = svc_pool_map_get();
503 
504         serv = __svc_create(prog, bufsize, npools, shutdown);
505 
506         if (serv != NULL) {
507                 serv->sv_function = func;
508                 serv->sv_module = mod;
509         }
510 
511         return serv;
512 }
513 EXPORT_SYMBOL_GPL(svc_create_pooled);
514 
515 void svc_shutdown_net(struct svc_serv *serv, struct net *net)
516 {
517         /*
518          * The set of xprts (contained in the sv_tempsocks and
519          * sv_permsocks lists) is now constant, since it is modified
520          * only by accepting new sockets (done by service threads in
521          * svc_recv) or aging old ones (done by sv_temptimer), or
522          * configuration changes (excluded by whatever locking the
523          * caller is using--nfsd_mutex in the case of nfsd).  So it's
524          * safe to traverse those lists and shut everything down:
525          */
526         svc_close_net(serv, net);
527 
528         if (serv->sv_shutdown)
529                 serv->sv_shutdown(serv, net);
530 }
531 EXPORT_SYMBOL_GPL(svc_shutdown_net);
532 
533 /*
534  * Destroy an RPC service. Should be called with appropriate locking to
535  * protect the sv_nrthreads, sv_permsocks and sv_tempsocks.
536  */
537 void
538 svc_destroy(struct svc_serv *serv)
539 {
540         dprintk("svc: svc_destroy(%s, %d)\n",
541                                 serv->sv_program->pg_name,
542                                 serv->sv_nrthreads);
543 
544         if (serv->sv_nrthreads) {
545                 if (--(serv->sv_nrthreads) != 0) {
546                         svc_sock_update_bufs(serv);
547                         return;
548                 }
549         } else
550                 printk("svc_destroy: no threads for serv=%p!\n", serv);
551 
552         del_timer_sync(&serv->sv_temptimer);
553 
554         /*
555          * The last user is gone and thus all sockets have to be destroyed to
556          * the point. Check this.
557          */
558         BUG_ON(!list_empty(&serv->sv_permsocks));
559         BUG_ON(!list_empty(&serv->sv_tempsocks));
560 
561         cache_clean_deferred(serv);
562 
563         if (svc_serv_is_pooled(serv))
564                 svc_pool_map_put();
565 
566         kfree(serv->sv_pools);
567         kfree(serv);
568 }
569 EXPORT_SYMBOL_GPL(svc_destroy);
570 
571 /*
572  * Allocate an RPC server's buffer space.
573  * We allocate pages and place them in rq_argpages.
574  */
575 static int
576 svc_init_buffer(struct svc_rqst *rqstp, unsigned int size, int node)
577 {
578         unsigned int pages, arghi;
579 
580         /* bc_xprt uses fore channel allocated buffers */
581         if (svc_is_backchannel(rqstp))
582                 return 1;
583 
584         pages = size / PAGE_SIZE + 1; /* extra page as we hold both request and reply.
585                                        * We assume one is at most one page
586                                        */
587         arghi = 0;
588         BUG_ON(pages > RPCSVC_MAXPAGES);
589         while (pages) {
590                 struct page *p = alloc_pages_node(node, GFP_KERNEL, 0);
591                 if (!p)
592                         break;
593                 rqstp->rq_pages[arghi++] = p;
594                 pages--;
595         }
596         return pages == 0;
597 }
598 
599 /*
600  * Release an RPC server buffer
601  */
602 static void
603 svc_release_buffer(struct svc_rqst *rqstp)
604 {
605         unsigned int i;
606 
607         for (i = 0; i < ARRAY_SIZE(rqstp->rq_pages); i++)
608                 if (rqstp->rq_pages[i])
609                         put_page(rqstp->rq_pages[i]);
610 }
611 
612 struct svc_rqst *
613 svc_prepare_thread(struct svc_serv *serv, struct svc_pool *pool, int node)
614 {
615         struct svc_rqst *rqstp;
616 
617         rqstp = kzalloc_node(sizeof(*rqstp), GFP_KERNEL, node);
618         if (!rqstp)
619                 goto out_enomem;
620 
621         init_waitqueue_head(&rqstp->rq_wait);
622 
623         serv->sv_nrthreads++;
624         spin_lock_bh(&pool->sp_lock);
625         pool->sp_nrthreads++;
626         list_add(&rqstp->rq_all, &pool->sp_all_threads);
627         spin_unlock_bh(&pool->sp_lock);
628         rqstp->rq_server = serv;
629         rqstp->rq_pool = pool;
630 
631         rqstp->rq_argp = kmalloc_node(serv->sv_xdrsize, GFP_KERNEL, node);
632         if (!rqstp->rq_argp)
633                 goto out_thread;
634 
635         rqstp->rq_resp = kmalloc_node(serv->sv_xdrsize, GFP_KERNEL, node);
636         if (!rqstp->rq_resp)
637                 goto out_thread;
638 
639         if (!svc_init_buffer(rqstp, serv->sv_max_mesg, node))
640                 goto out_thread;
641 
642         return rqstp;
643 out_thread:
644         svc_exit_thread(rqstp);
645 out_enomem:
646         return ERR_PTR(-ENOMEM);
647 }
648 EXPORT_SYMBOL_GPL(svc_prepare_thread);
649 
650 /*
651  * Choose a pool in which to create a new thread, for svc_set_num_threads
652  */
653 static inline struct svc_pool *
654 choose_pool(struct svc_serv *serv, struct svc_pool *pool, unsigned int *state)
655 {
656         if (pool != NULL)
657                 return pool;
658 
659         return &serv->sv_pools[(*state)++ % serv->sv_nrpools];
660 }
661 
662 /*
663  * Choose a thread to kill, for svc_set_num_threads
664  */
665 static inline struct task_struct *
666 choose_victim(struct svc_serv *serv, struct svc_pool *pool, unsigned int *state)
667 {
668         unsigned int i;
669         struct task_struct *task = NULL;
670 
671         if (pool != NULL) {
672                 spin_lock_bh(&pool->sp_lock);
673         } else {
674                 /* choose a pool in round-robin fashion */
675                 for (i = 0; i < serv->sv_nrpools; i++) {
676                         pool = &serv->sv_pools[--(*state) % serv->sv_nrpools];
677                         spin_lock_bh(&pool->sp_lock);
678                         if (!list_empty(&pool->sp_all_threads))
679                                 goto found_pool;
680                         spin_unlock_bh(&pool->sp_lock);
681                 }
682                 return NULL;
683         }
684 
685 found_pool:
686         if (!list_empty(&pool->sp_all_threads)) {
687                 struct svc_rqst *rqstp;
688 
689                 /*
690                  * Remove from the pool->sp_all_threads list
691                  * so we don't try to kill it again.
692                  */
693                 rqstp = list_entry(pool->sp_all_threads.next, struct svc_rqst, rq_all);
694                 list_del_init(&rqstp->rq_all);
695                 task = rqstp->rq_task;
696         }
697         spin_unlock_bh(&pool->sp_lock);
698 
699         return task;
700 }
701 
702 /*
703  * Create or destroy enough new threads to make the number
704  * of threads the given number.  If `pool' is non-NULL, applies
705  * only to threads in that pool, otherwise round-robins between
706  * all pools.  Caller must ensure that mutual exclusion between this and
707  * server startup or shutdown.
708  *
709  * Destroying threads relies on the service threads filling in
710  * rqstp->rq_task, which only the nfs ones do.  Assumes the serv
711  * has been created using svc_create_pooled().
712  *
713  * Based on code that used to be in nfsd_svc() but tweaked
714  * to be pool-aware.
715  */
716 int
717 svc_set_num_threads(struct svc_serv *serv, struct svc_pool *pool, int nrservs)
718 {
719         struct svc_rqst *rqstp;
720         struct task_struct *task;
721         struct svc_pool *chosen_pool;
722         int error = 0;
723         unsigned int state = serv->sv_nrthreads-1;
724         int node;
725 
726         if (pool == NULL) {
727                 /* The -1 assumes caller has done a svc_get() */
728                 nrservs -= (serv->sv_nrthreads-1);
729         } else {
730                 spin_lock_bh(&pool->sp_lock);
731                 nrservs -= pool->sp_nrthreads;
732                 spin_unlock_bh(&pool->sp_lock);
733         }
734 
735         /* create new threads */
736         while (nrservs > 0) {
737                 nrservs--;
738                 chosen_pool = choose_pool(serv, pool, &state);
739 
740                 node = svc_pool_map_get_node(chosen_pool->sp_id);
741                 rqstp = svc_prepare_thread(serv, chosen_pool, node);
742                 if (IS_ERR(rqstp)) {
743                         error = PTR_ERR(rqstp);
744                         break;
745                 }
746 
747                 __module_get(serv->sv_module);
748                 task = kthread_create_on_node(serv->sv_function, rqstp,
749                                               node, serv->sv_name);
750                 if (IS_ERR(task)) {
751                         error = PTR_ERR(task);
752                         module_put(serv->sv_module);
753                         svc_exit_thread(rqstp);
754                         break;
755                 }
756 
757                 rqstp->rq_task = task;
758                 if (serv->sv_nrpools > 1)
759                         svc_pool_map_set_cpumask(task, chosen_pool->sp_id);
760 
761                 svc_sock_update_bufs(serv);
762                 wake_up_process(task);
763         }
764         /* destroy old threads */
765         while (nrservs < 0 &&
766                (task = choose_victim(serv, pool, &state)) != NULL) {
767                 send_sig(SIGINT, task, 1);
768                 nrservs++;
769         }
770 
771         return error;
772 }
773 EXPORT_SYMBOL_GPL(svc_set_num_threads);
774 
775 /*
776  * Called from a server thread as it's exiting. Caller must hold the BKL or
777  * the "service mutex", whichever is appropriate for the service.
778  */
779 void
780 svc_exit_thread(struct svc_rqst *rqstp)
781 {
782         struct svc_serv *serv = rqstp->rq_server;
783         struct svc_pool *pool = rqstp->rq_pool;
784 
785         svc_release_buffer(rqstp);
786         kfree(rqstp->rq_resp);
787         kfree(rqstp->rq_argp);
788         kfree(rqstp->rq_auth_data);
789 
790         spin_lock_bh(&pool->sp_lock);
791         pool->sp_nrthreads--;
792         list_del(&rqstp->rq_all);
793         spin_unlock_bh(&pool->sp_lock);
794 
795         kfree(rqstp);
796 
797         /* Release the server */
798         if (serv)
799                 svc_destroy(serv);
800 }
801 EXPORT_SYMBOL_GPL(svc_exit_thread);
802 
803 /*
804  * Register an "inet" protocol family netid with the local
805  * rpcbind daemon via an rpcbind v4 SET request.
806  *
807  * No netconfig infrastructure is available in the kernel, so
808  * we map IP_ protocol numbers to netids by hand.
809  *
810  * Returns zero on success; a negative errno value is returned
811  * if any error occurs.
812  */
813 static int __svc_rpcb_register4(struct net *net, const u32 program,
814                                 const u32 version,
815                                 const unsigned short protocol,
816                                 const unsigned short port)
817 {
818         const struct sockaddr_in sin = {
819                 .sin_family             = AF_INET,
820                 .sin_addr.s_addr        = htonl(INADDR_ANY),
821                 .sin_port               = htons(port),
822         };
823         const char *netid;
824         int error;
825 
826         switch (protocol) {
827         case IPPROTO_UDP:
828                 netid = RPCBIND_NETID_UDP;
829                 break;
830         case IPPROTO_TCP:
831                 netid = RPCBIND_NETID_TCP;
832                 break;
833         default:
834                 return -ENOPROTOOPT;
835         }
836 
837         error = rpcb_v4_register(net, program, version,
838                                         (const struct sockaddr *)&sin, netid);
839 
840         /*
841          * User space didn't support rpcbind v4, so retry this
842          * registration request with the legacy rpcbind v2 protocol.
843          */
844         if (error == -EPROTONOSUPPORT)
845                 error = rpcb_register(net, program, version, protocol, port);
846 
847         return error;
848 }
849 
850 #if IS_ENABLED(CONFIG_IPV6)
851 /*
852  * Register an "inet6" protocol family netid with the local
853  * rpcbind daemon via an rpcbind v4 SET request.
854  *
855  * No netconfig infrastructure is available in the kernel, so
856  * we map IP_ protocol numbers to netids by hand.
857  *
858  * Returns zero on success; a negative errno value is returned
859  * if any error occurs.
860  */
861 static int __svc_rpcb_register6(struct net *net, const u32 program,
862                                 const u32 version,
863                                 const unsigned short protocol,
864                                 const unsigned short port)
865 {
866         const struct sockaddr_in6 sin6 = {
867                 .sin6_family            = AF_INET6,
868                 .sin6_addr              = IN6ADDR_ANY_INIT,
869                 .sin6_port              = htons(port),
870         };
871         const char *netid;
872         int error;
873 
874         switch (protocol) {
875         case IPPROTO_UDP:
876                 netid = RPCBIND_NETID_UDP6;
877                 break;
878         case IPPROTO_TCP:
879                 netid = RPCBIND_NETID_TCP6;
880                 break;
881         default:
882                 return -ENOPROTOOPT;
883         }
884 
885         error = rpcb_v4_register(net, program, version,
886                                         (const struct sockaddr *)&sin6, netid);
887 
888         /*
889          * User space didn't support rpcbind version 4, so we won't
890          * use a PF_INET6 listener.
891          */
892         if (error == -EPROTONOSUPPORT)
893                 error = -EAFNOSUPPORT;
894 
895         return error;
896 }
897 #endif  /* IS_ENABLED(CONFIG_IPV6) */
898 
899 /*
900  * Register a kernel RPC service via rpcbind version 4.
901  *
902  * Returns zero on success; a negative errno value is returned
903  * if any error occurs.
904  */
905 static int __svc_register(struct net *net, const char *progname,
906                           const u32 program, const u32 version,
907                           const int family,
908                           const unsigned short protocol,
909                           const unsigned short port)
910 {
911         int error = -EAFNOSUPPORT;
912 
913         switch (family) {
914         case PF_INET:
915                 error = __svc_rpcb_register4(net, program, version,
916                                                 protocol, port);
917                 break;
918 #if IS_ENABLED(CONFIG_IPV6)
919         case PF_INET6:
920                 error = __svc_rpcb_register6(net, program, version,
921                                                 protocol, port);
922 #endif
923         }
924 
925         if (error < 0)
926                 printk(KERN_WARNING "svc: failed to register %sv%u RPC "
927                         "service (errno %d).\n", progname, version, -error);
928         return error;
929 }
930 
931 /**
932  * svc_register - register an RPC service with the local portmapper
933  * @serv: svc_serv struct for the service to register
934  * @net: net namespace for the service to register
935  * @family: protocol family of service's listener socket
936  * @proto: transport protocol number to advertise
937  * @port: port to advertise
938  *
939  * Service is registered for any address in the passed-in protocol family
940  */
941 int svc_register(const struct svc_serv *serv, struct net *net,
942                  const int family, const unsigned short proto,
943                  const unsigned short port)
944 {
945         struct svc_program      *progp;
946         unsigned int            i;
947         int                     error = 0;
948 
949         BUG_ON(proto == 0 && port == 0);
950 
951         for (progp = serv->sv_program; progp; progp = progp->pg_next) {
952                 for (i = 0; i < progp->pg_nvers; i++) {
953                         if (progp->pg_vers[i] == NULL)
954                                 continue;
955 
956                         dprintk("svc: svc_register(%sv%d, %s, %u, %u)%s\n",
957                                         progp->pg_name,
958                                         i,
959                                         proto == IPPROTO_UDP?  "udp" : "tcp",
960                                         port,
961                                         family,
962                                         progp->pg_vers[i]->vs_hidden?
963                                                 " (but not telling portmap)" : "");
964 
965                         if (progp->pg_vers[i]->vs_hidden)
966                                 continue;
967 
968                         error = __svc_register(net, progp->pg_name, progp->pg_prog,
969                                                 i, family, proto, port);
970                         if (error < 0)
971                                 break;
972                 }
973         }
974 
975         return error;
976 }
977 
978 /*
979  * If user space is running rpcbind, it should take the v4 UNSET
980  * and clear everything for this [program, version].  If user space
981  * is running portmap, it will reject the v4 UNSET, but won't have
982  * any "inet6" entries anyway.  So a PMAP_UNSET should be sufficient
983  * in this case to clear all existing entries for [program, version].
984  */
985 static void __svc_unregister(struct net *net, const u32 program, const u32 version,
986                              const char *progname)
987 {
988         int error;
989 
990         error = rpcb_v4_register(net, program, version, NULL, "");
991 
992         /*
993          * User space didn't support rpcbind v4, so retry this
994          * request with the legacy rpcbind v2 protocol.
995          */
996         if (error == -EPROTONOSUPPORT)
997                 error = rpcb_register(net, program, version, 0, 0);
998 
999         dprintk("svc: %s(%sv%u), error %d\n",
1000                         __func__, progname, version, error);
1001 }
1002 
1003 /*
1004  * All netids, bind addresses and ports registered for [program, version]
1005  * are removed from the local rpcbind database (if the service is not
1006  * hidden) to make way for a new instance of the service.
1007  *
1008  * The result of unregistration is reported via dprintk for those who want
1009  * verification of the result, but is otherwise not important.
1010  */
1011 static void svc_unregister(const struct svc_serv *serv, struct net *net)
1012 {
1013         struct svc_program *progp;
1014         unsigned long flags;
1015         unsigned int i;
1016 
1017         clear_thread_flag(TIF_SIGPENDING);
1018 
1019         for (progp = serv->sv_program; progp; progp = progp->pg_next) {
1020                 for (i = 0; i < progp->pg_nvers; i++) {
1021                         if (progp->pg_vers[i] == NULL)
1022                                 continue;
1023                         if (progp->pg_vers[i]->vs_hidden)
1024                                 continue;
1025 
1026                         dprintk("svc: attempting to unregister %sv%u\n",
1027                                 progp->pg_name, i);
1028                         __svc_unregister(net, progp->pg_prog, i, progp->pg_name);
1029                 }
1030         }
1031 
1032         spin_lock_irqsave(&current->sighand->siglock, flags);
1033         recalc_sigpending();
1034         spin_unlock_irqrestore(&current->sighand->siglock, flags);
1035 }
1036 
1037 /*
1038  * Printk the given error with the address of the client that caused it.
1039  */
1040 static __printf(2, 3)
1041 void svc_printk(struct svc_rqst *rqstp, const char *fmt, ...)
1042 {
1043         struct va_format vaf;
1044         va_list args;
1045         char    buf[RPC_MAX_ADDRBUFLEN];
1046 
1047         va_start(args, fmt);
1048 
1049         vaf.fmt = fmt;
1050         vaf.va = &args;
1051 
1052         net_warn_ratelimited("svc: %s: %pV",
1053                              svc_print_addr(rqstp, buf, sizeof(buf)), &vaf);
1054 
1055         va_end(args);
1056 }
1057 
1058 /*
1059  * Common routine for processing the RPC request.
1060  */
1061 static int
1062 svc_process_common(struct svc_rqst *rqstp, struct kvec *argv, struct kvec *resv)
1063 {
1064         struct svc_program      *progp;
1065         struct svc_version      *versp = NULL;  /* compiler food */
1066         struct svc_procedure    *procp = NULL;
1067         struct svc_serv         *serv = rqstp->rq_server;
1068         kxdrproc_t              xdr;
1069         __be32                  *statp;
1070         u32                     prog, vers, proc;
1071         __be32                  auth_stat, rpc_stat;
1072         int                     auth_res;
1073         __be32                  *reply_statp;
1074 
1075         rpc_stat = rpc_success;
1076 
1077         if (argv->iov_len < 6*4)
1078                 goto err_short_len;
1079 
1080         /* Will be turned off only in gss privacy case: */
1081         rqstp->rq_splice_ok = 1;
1082         /* Will be turned off only when NFSv4 Sessions are used */
1083         rqstp->rq_usedeferral = 1;
1084         rqstp->rq_dropme = false;
1085 
1086         /* Setup reply header */
1087         rqstp->rq_xprt->xpt_ops->xpo_prep_reply_hdr(rqstp);
1088 
1089         svc_putu32(resv, rqstp->rq_xid);
1090 
1091         vers = svc_getnl(argv);
1092 
1093         /* First words of reply: */
1094         svc_putnl(resv, 1);             /* REPLY */
1095 
1096         if (vers != 2)          /* RPC version number */
1097                 goto err_bad_rpc;
1098 
1099         /* Save position in case we later decide to reject: */
1100         reply_statp = resv->iov_base + resv->iov_len;
1101 
1102         svc_putnl(resv, 0);             /* ACCEPT */
1103 
1104         rqstp->rq_prog = prog = svc_getnl(argv);        /* program number */
1105         rqstp->rq_vers = vers = svc_getnl(argv);        /* version number */
1106         rqstp->rq_proc = proc = svc_getnl(argv);        /* procedure number */
1107 
1108         progp = serv->sv_program;
1109 
1110         for (progp = serv->sv_program; progp; progp = progp->pg_next)
1111                 if (prog == progp->pg_prog)
1112                         break;
1113 
1114         /*
1115          * Decode auth data, and add verifier to reply buffer.
1116          * We do this before anything else in order to get a decent
1117          * auth verifier.
1118          */
1119         auth_res = svc_authenticate(rqstp, &auth_stat);
1120         /* Also give the program a chance to reject this call: */
1121         if (auth_res == SVC_OK && progp) {
1122                 auth_stat = rpc_autherr_badcred;
1123                 auth_res = progp->pg_authenticate(rqstp);
1124         }
1125         switch (auth_res) {
1126         case SVC_OK:
1127                 break;
1128         case SVC_GARBAGE:
1129                 goto err_garbage;
1130         case SVC_SYSERR:
1131                 rpc_stat = rpc_system_err;
1132                 goto err_bad;
1133         case SVC_DENIED:
1134                 goto err_bad_auth;
1135         case SVC_CLOSE:
1136                 if (test_bit(XPT_TEMP, &rqstp->rq_xprt->xpt_flags))
1137                         svc_close_xprt(rqstp->rq_xprt);
1138         case SVC_DROP:
1139                 goto dropit;
1140         case SVC_COMPLETE:
1141                 goto sendit;
1142         }
1143 
1144         if (progp == NULL)
1145                 goto err_bad_prog;
1146 
1147         if (vers >= progp->pg_nvers ||
1148           !(versp = progp->pg_vers[vers]))
1149                 goto err_bad_vers;
1150 
1151         procp = versp->vs_proc + proc;
1152         if (proc >= versp->vs_nproc || !procp->pc_func)
1153                 goto err_bad_proc;
1154         rqstp->rq_procinfo = procp;
1155 
1156         /* Syntactic check complete */
1157         serv->sv_stats->rpccnt++;
1158 
1159         /* Build the reply header. */
1160         statp = resv->iov_base +resv->iov_len;
1161         svc_putnl(resv, RPC_SUCCESS);
1162 
1163         /* Bump per-procedure stats counter */
1164         procp->pc_count++;
1165 
1166         /* Initialize storage for argp and resp */
1167         memset(rqstp->rq_argp, 0, procp->pc_argsize);
1168         memset(rqstp->rq_resp, 0, procp->pc_ressize);
1169 
1170         /* un-reserve some of the out-queue now that we have a
1171          * better idea of reply size
1172          */
1173         if (procp->pc_xdrressize)
1174                 svc_reserve_auth(rqstp, procp->pc_xdrressize<<2);
1175 
1176         /* Call the function that processes the request. */
1177         if (!versp->vs_dispatch) {
1178                 /* Decode arguments */
1179                 xdr = procp->pc_decode;
1180                 if (xdr && !xdr(rqstp, argv->iov_base, rqstp->rq_argp))
1181                         goto err_garbage;
1182 
1183                 *statp = procp->pc_func(rqstp, rqstp->rq_argp, rqstp->rq_resp);
1184 
1185                 /* Encode reply */
1186                 if (rqstp->rq_dropme) {
1187                         if (procp->pc_release)
1188                                 procp->pc_release(rqstp, NULL, rqstp->rq_resp);
1189                         goto dropit;
1190                 }
1191                 if (*statp == rpc_success &&
1192                     (xdr = procp->pc_encode) &&
1193                     !xdr(rqstp, resv->iov_base+resv->iov_len, rqstp->rq_resp)) {
1194                         dprintk("svc: failed to encode reply\n");
1195                         /* serv->sv_stats->rpcsystemerr++; */
1196                         *statp = rpc_system_err;
1197                 }
1198         } else {
1199                 dprintk("svc: calling dispatcher\n");
1200                 if (!versp->vs_dispatch(rqstp, statp)) {
1201                         /* Release reply info */
1202                         if (procp->pc_release)
1203                                 procp->pc_release(rqstp, NULL, rqstp->rq_resp);
1204                         goto dropit;
1205                 }
1206         }
1207 
1208         /* Check RPC status result */
1209         if (*statp != rpc_success)
1210                 resv->iov_len = ((void*)statp)  - resv->iov_base + 4;
1211 
1212         /* Release reply info */
1213         if (procp->pc_release)
1214                 procp->pc_release(rqstp, NULL, rqstp->rq_resp);
1215 
1216         if (procp->pc_encode == NULL)
1217                 goto dropit;
1218 
1219  sendit:
1220         if (svc_authorise(rqstp))
1221                 goto dropit;
1222         return 1;               /* Caller can now send it */
1223 
1224  dropit:
1225         svc_authorise(rqstp);   /* doesn't hurt to call this twice */
1226         dprintk("svc: svc_process dropit\n");
1227         return 0;
1228 
1229 err_short_len:
1230         svc_printk(rqstp, "short len %Zd, dropping request\n",
1231                         argv->iov_len);
1232 
1233         goto dropit;                    /* drop request */
1234 
1235 err_bad_rpc:
1236         serv->sv_stats->rpcbadfmt++;
1237         svc_putnl(resv, 1);     /* REJECT */
1238         svc_putnl(resv, 0);     /* RPC_MISMATCH */
1239         svc_putnl(resv, 2);     /* Only RPCv2 supported */
1240         svc_putnl(resv, 2);
1241         goto sendit;
1242 
1243 err_bad_auth:
1244         dprintk("svc: authentication failed (%d)\n", ntohl(auth_stat));
1245         serv->sv_stats->rpcbadauth++;
1246         /* Restore write pointer to location of accept status: */
1247         xdr_ressize_check(rqstp, reply_statp);
1248         svc_putnl(resv, 1);     /* REJECT */
1249         svc_putnl(resv, 1);     /* AUTH_ERROR */
1250         svc_putnl(resv, ntohl(auth_stat));      /* status */
1251         goto sendit;
1252 
1253 err_bad_prog:
1254         dprintk("svc: unknown program %d\n", prog);
1255         serv->sv_stats->rpcbadfmt++;
1256         svc_putnl(resv, RPC_PROG_UNAVAIL);
1257         goto sendit;
1258 
1259 err_bad_vers:
1260         svc_printk(rqstp, "unknown version (%d for prog %d, %s)\n",
1261                        vers, prog, progp->pg_name);
1262 
1263         serv->sv_stats->rpcbadfmt++;
1264         svc_putnl(resv, RPC_PROG_MISMATCH);
1265         svc_putnl(resv, progp->pg_lovers);
1266         svc_putnl(resv, progp->pg_hivers);
1267         goto sendit;
1268 
1269 err_bad_proc:
1270         svc_printk(rqstp, "unknown procedure (%d)\n", proc);
1271 
1272         serv->sv_stats->rpcbadfmt++;
1273         svc_putnl(resv, RPC_PROC_UNAVAIL);
1274         goto sendit;
1275 
1276 err_garbage:
1277         svc_printk(rqstp, "failed to decode args\n");
1278 
1279         rpc_stat = rpc_garbage_args;
1280 err_bad:
1281         serv->sv_stats->rpcbadfmt++;
1282         svc_putnl(resv, ntohl(rpc_stat));
1283         goto sendit;
1284 }
1285 EXPORT_SYMBOL_GPL(svc_process);
1286 
1287 /*
1288  * Process the RPC request.
1289  */
1290 int
1291 svc_process(struct svc_rqst *rqstp)
1292 {
1293         struct kvec             *argv = &rqstp->rq_arg.head[0];
1294         struct kvec             *resv = &rqstp->rq_res.head[0];
1295         struct svc_serv         *serv = rqstp->rq_server;
1296         u32                     dir;
1297 
1298         /*
1299          * Setup response xdr_buf.
1300          * Initially it has just one page
1301          */
1302         rqstp->rq_resused = 1;
1303         resv->iov_base = page_address(rqstp->rq_respages[0]);
1304         resv->iov_len = 0;
1305         rqstp->rq_res.pages = rqstp->rq_respages + 1;
1306         rqstp->rq_res.len = 0;
1307         rqstp->rq_res.page_base = 0;
1308         rqstp->rq_res.page_len = 0;
1309         rqstp->rq_res.buflen = PAGE_SIZE;
1310         rqstp->rq_res.tail[0].iov_base = NULL;
1311         rqstp->rq_res.tail[0].iov_len = 0;
1312 
1313         rqstp->rq_xid = svc_getu32(argv);
1314 
1315         dir  = svc_getnl(argv);
1316         if (dir != 0) {
1317                 /* direction != CALL */
1318                 svc_printk(rqstp, "bad direction %d, dropping request\n", dir);
1319                 serv->sv_stats->rpcbadfmt++;
1320                 svc_drop(rqstp);
1321                 return 0;
1322         }
1323 
1324         /* Returns 1 for send, 0 for drop */
1325         if (svc_process_common(rqstp, argv, resv))
1326                 return svc_send(rqstp);
1327         else {
1328                 svc_drop(rqstp);
1329                 return 0;
1330         }
1331 }
1332 
1333 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
1334 /*
1335  * Process a backchannel RPC request that arrived over an existing
1336  * outbound connection
1337  */
1338 int
1339 bc_svc_process(struct svc_serv *serv, struct rpc_rqst *req,
1340                struct svc_rqst *rqstp)
1341 {
1342         struct kvec     *argv = &rqstp->rq_arg.head[0];
1343         struct kvec     *resv = &rqstp->rq_res.head[0];
1344 
1345         /* Build the svc_rqst used by the common processing routine */
1346         rqstp->rq_xprt = serv->sv_bc_xprt;
1347         rqstp->rq_xid = req->rq_xid;
1348         rqstp->rq_prot = req->rq_xprt->prot;
1349         rqstp->rq_server = serv;
1350 
1351         rqstp->rq_addrlen = sizeof(req->rq_xprt->addr);
1352         memcpy(&rqstp->rq_addr, &req->rq_xprt->addr, rqstp->rq_addrlen);
1353         memcpy(&rqstp->rq_arg, &req->rq_rcv_buf, sizeof(rqstp->rq_arg));
1354         memcpy(&rqstp->rq_res, &req->rq_snd_buf, sizeof(rqstp->rq_res));
1355 
1356         /* reset result send buffer "put" position */
1357         resv->iov_len = 0;
1358 
1359         if (rqstp->rq_prot != IPPROTO_TCP) {
1360                 printk(KERN_ERR "No support for Non-TCP transports!\n");
1361                 BUG();
1362         }
1363 
1364         /*
1365          * Skip the next two words because they've already been
1366          * processed in the trasport
1367          */
1368         svc_getu32(argv);       /* XID */
1369         svc_getnl(argv);        /* CALLDIR */
1370 
1371         /* Returns 1 for send, 0 for drop */
1372         if (svc_process_common(rqstp, argv, resv)) {
1373                 memcpy(&req->rq_snd_buf, &rqstp->rq_res,
1374                                                 sizeof(req->rq_snd_buf));
1375                 return bc_send(req);
1376         } else {
1377                 /* drop request */
1378                 xprt_free_bc_request(req);
1379                 return 0;
1380         }
1381 }
1382 EXPORT_SYMBOL_GPL(bc_svc_process);
1383 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
1384 
1385 /*
1386  * Return (transport-specific) limit on the rpc payload.
1387  */
1388 u32 svc_max_payload(const struct svc_rqst *rqstp)
1389 {
1390         u32 max = rqstp->rq_xprt->xpt_class->xcl_max_payload;
1391 
1392         if (rqstp->rq_server->sv_max_payload < max)
1393                 max = rqstp->rq_server->sv_max_payload;
1394         return max;
1395 }
1396 EXPORT_SYMBOL_GPL(svc_max_payload);
1397 

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