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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
24#include <linux/sunrpc/types.h>
25#include <linux/sunrpc/xdr.h>
26#include <linux/sunrpc/stats.h>
27#include <linux/sunrpc/svcsock.h>
28#include <linux/sunrpc/clnt.h>
29#include <linux/sunrpc/bc_xprt.h>
30
31#include <trace/events/sunrpc.h>
32
33#define RPCDBG_FACILITY RPCDBG_SVCDSP
34
35static void svc_unregister(const struct svc_serv *serv, struct net *net);
36
37#define svc_serv_is_pooled(serv) ((serv)->sv_ops->svo_function)
38
39#define SVC_POOL_DEFAULT SVC_POOL_GLOBAL
40
41/*
42 * Structure for mapping cpus to pools and vice versa.
43 * Setup once during sunrpc initialisation.
44 */
45struct svc_pool_map svc_pool_map = {
46 .mode = SVC_POOL_DEFAULT
47};
48EXPORT_SYMBOL_GPL(svc_pool_map);
49
50static DEFINE_MUTEX(svc_pool_map_mutex);/* protects svc_pool_map.count only */
51
52static int
53param_set_pool_mode(const char *val, struct kernel_param *kp)
54{
55 int *ip = (int *)kp->arg;
56 struct svc_pool_map *m = &svc_pool_map;
57 int err;
58
59 mutex_lock(&svc_pool_map_mutex);
60
61 err = -EBUSY;
62 if (m->count)
63 goto out;
64
65 err = 0;
66 if (!strncmp(val, "auto", 4))
67 *ip = SVC_POOL_AUTO;
68 else if (!strncmp(val, "global", 6))
69 *ip = SVC_POOL_GLOBAL;
70 else if (!strncmp(val, "percpu", 6))
71 *ip = SVC_POOL_PERCPU;
72 else if (!strncmp(val, "pernode", 7))
73 *ip = SVC_POOL_PERNODE;
74 else
75 err = -EINVAL;
76
77out:
78 mutex_unlock(&svc_pool_map_mutex);
79 return err;
80}
81
82static int
83param_get_pool_mode(char *buf, struct kernel_param *kp)
84{
85 int *ip = (int *)kp->arg;
86
87 switch (*ip)
88 {
89 case SVC_POOL_AUTO:
90 return strlcpy(buf, "auto", 20);
91 case SVC_POOL_GLOBAL:
92 return strlcpy(buf, "global", 20);
93 case SVC_POOL_PERCPU:
94 return strlcpy(buf, "percpu", 20);
95 case SVC_POOL_PERNODE:
96 return strlcpy(buf, "pernode", 20);
97 default:
98 return sprintf(buf, "%d", *ip);
99 }
100}
101
102module_param_call(pool_mode, param_set_pool_mode, param_get_pool_mode,
103 &svc_pool_map.mode, 0644);
104
105/*
106 * Detect best pool mapping mode heuristically,
107 * according to the machine's topology.
108 */
109static int
110svc_pool_map_choose_mode(void)
111{
112 unsigned int node;
113
114 if (nr_online_nodes > 1) {
115 /*
116 * Actually have multiple NUMA nodes,
117 * so split pools on NUMA node boundaries
118 */
119 return SVC_POOL_PERNODE;
120 }
121
122 node = first_online_node;
123 if (nr_cpus_node(node) > 2) {
124 /*
125 * Non-trivial SMP, or CONFIG_NUMA on
126 * non-NUMA hardware, e.g. with a generic
127 * x86_64 kernel on Xeons. In this case we
128 * want to divide the pools on cpu boundaries.
129 */
130 return SVC_POOL_PERCPU;
131 }
132
133 /* default: one global pool */
134 return SVC_POOL_GLOBAL;
135}
136
137/*
138 * Allocate the to_pool[] and pool_to[] arrays.
139 * Returns 0 on success or an errno.
140 */
141static int
142svc_pool_map_alloc_arrays(struct svc_pool_map *m, unsigned int maxpools)
143{
144 m->to_pool = kcalloc(maxpools, sizeof(unsigned int), GFP_KERNEL);
145 if (!m->to_pool)
146 goto fail;
147 m->pool_to = kcalloc(maxpools, sizeof(unsigned int), GFP_KERNEL);
148 if (!m->pool_to)
149 goto fail_free;
150
151 return 0;
152
153fail_free:
154 kfree(m->to_pool);
155 m->to_pool = NULL;
156fail:
157 return -ENOMEM;
158}
159
160/*
161 * Initialise the pool map for SVC_POOL_PERCPU mode.
162 * Returns number of pools or <0 on error.
163 */
164static int
165svc_pool_map_init_percpu(struct svc_pool_map *m)
166{
167 unsigned int maxpools = nr_cpu_ids;
168 unsigned int pidx = 0;
169 unsigned int cpu;
170 int err;
171
172 err = svc_pool_map_alloc_arrays(m, maxpools);
173 if (err)
174 return err;
175
176 for_each_online_cpu(cpu) {
177 BUG_ON(pidx >= maxpools);
178 m->to_pool[cpu] = pidx;
179 m->pool_to[pidx] = cpu;
180 pidx++;
181 }
182 /* cpus brought online later all get mapped to pool0, sorry */
183
184 return pidx;
185};
186
187
188/*
189 * Initialise the pool map for SVC_POOL_PERNODE mode.
190 * Returns number of pools or <0 on error.
191 */
192static int
193svc_pool_map_init_pernode(struct svc_pool_map *m)
194{
195 unsigned int maxpools = nr_node_ids;
196 unsigned int pidx = 0;
197 unsigned int node;
198 int err;
199
200 err = svc_pool_map_alloc_arrays(m, maxpools);
201 if (err)
202 return err;
203
204 for_each_node_with_cpus(node) {
205 /* some architectures (e.g. SN2) have cpuless nodes */
206 BUG_ON(pidx > maxpools);
207 m->to_pool[node] = pidx;
208 m->pool_to[pidx] = node;
209 pidx++;
210 }
211 /* nodes brought online later all get mapped to pool0, sorry */
212
213 return pidx;
214}
215
216
217/*
218 * Add a reference to the global map of cpus to pools (and
219 * vice versa). Initialise the map if we're the first user.
220 * Returns the number of pools.
221 */
222unsigned int
223svc_pool_map_get(void)
224{
225 struct svc_pool_map *m = &svc_pool_map;
226 int npools = -1;
227
228 mutex_lock(&svc_pool_map_mutex);
229
230 if (m->count++) {
231 mutex_unlock(&svc_pool_map_mutex);
232 return m->npools;
233 }
234
235 if (m->mode == SVC_POOL_AUTO)
236 m->mode = svc_pool_map_choose_mode();
237
238 switch (m->mode) {
239 case SVC_POOL_PERCPU:
240 npools = svc_pool_map_init_percpu(m);
241 break;
242 case SVC_POOL_PERNODE:
243 npools = svc_pool_map_init_pernode(m);
244 break;
245 }
246
247 if (npools < 0) {
248 /* default, or memory allocation failure */
249 npools = 1;
250 m->mode = SVC_POOL_GLOBAL;
251 }
252 m->npools = npools;
253
254 mutex_unlock(&svc_pool_map_mutex);
255 return m->npools;
256}
257EXPORT_SYMBOL_GPL(svc_pool_map_get);
258
259/*
260 * Drop a reference to the global map of cpus to pools.
261 * When the last reference is dropped, the map data is
262 * freed; this allows the sysadmin to change the pool
263 * mode using the pool_mode module option without
264 * rebooting or re-loading sunrpc.ko.
265 */
266void
267svc_pool_map_put(void)
268{
269 struct svc_pool_map *m = &svc_pool_map;
270
271 mutex_lock(&svc_pool_map_mutex);
272
273 if (!--m->count) {
274 kfree(m->to_pool);
275 m->to_pool = NULL;
276 kfree(m->pool_to);
277 m->pool_to = NULL;
278 m->npools = 0;
279 }
280
281 mutex_unlock(&svc_pool_map_mutex);
282}
283EXPORT_SYMBOL_GPL(svc_pool_map_put);
284
285static int svc_pool_map_get_node(unsigned int pidx)
286{
287 const struct svc_pool_map *m = &svc_pool_map;
288
289 if (m->count) {
290 if (m->mode == SVC_POOL_PERCPU)
291 return cpu_to_node(m->pool_to[pidx]);
292 if (m->mode == SVC_POOL_PERNODE)
293 return m->pool_to[pidx];
294 }
295 return NUMA_NO_NODE;
296}
297/*
298 * Set the given thread's cpus_allowed mask so that it
299 * will only run on cpus in the given pool.
300 */
301static inline void
302svc_pool_map_set_cpumask(struct task_struct *task, unsigned int pidx)
303{
304 struct svc_pool_map *m = &svc_pool_map;
305 unsigned int node = m->pool_to[pidx];
306
307 /*
308 * The caller checks for sv_nrpools > 1, which
309 * implies that we've been initialized.
310 */
311 WARN_ON_ONCE(m->count == 0);
312 if (m->count == 0)
313 return;
314
315 switch (m->mode) {
316 case SVC_POOL_PERCPU:
317 {
318 set_cpus_allowed_ptr(task, cpumask_of(node));
319 break;
320 }
321 case SVC_POOL_PERNODE:
322 {
323 set_cpus_allowed_ptr(task, cpumask_of_node(node));
324 break;
325 }
326 }
327}
328
329/*
330 * Use the mapping mode to choose a pool for a given CPU.
331 * Used when enqueueing an incoming RPC. Always returns
332 * a non-NULL pool pointer.
333 */
334struct svc_pool *
335svc_pool_for_cpu(struct svc_serv *serv, int cpu)
336{
337 struct svc_pool_map *m = &svc_pool_map;
338 unsigned int pidx = 0;
339
340 /*
341 * An uninitialised map happens in a pure client when
342 * lockd is brought up, so silently treat it the
343 * same as SVC_POOL_GLOBAL.
344 */
345 if (svc_serv_is_pooled(serv)) {
346 switch (m->mode) {
347 case SVC_POOL_PERCPU:
348 pidx = m->to_pool[cpu];
349 break;
350 case SVC_POOL_PERNODE:
351 pidx = m->to_pool[cpu_to_node(cpu)];
352 break;
353 }
354 }
355 return &serv->sv_pools[pidx % serv->sv_nrpools];
356}
357
358int svc_rpcb_setup(struct svc_serv *serv, struct net *net)
359{
360 int err;
361
362 err = rpcb_create_local(net);
363 if (err)
364 return err;
365
366 /* Remove any stale portmap registrations */
367 svc_unregister(serv, net);
368 return 0;
369}
370EXPORT_SYMBOL_GPL(svc_rpcb_setup);
371
372void svc_rpcb_cleanup(struct svc_serv *serv, struct net *net)
373{
374 svc_unregister(serv, net);
375 rpcb_put_local(net);
376}
377EXPORT_SYMBOL_GPL(svc_rpcb_cleanup);
378
379static int svc_uses_rpcbind(struct svc_serv *serv)
380{
381 struct svc_program *progp;
382 unsigned int i;
383
384 for (progp = serv->sv_program; progp; progp = progp->pg_next) {
385 for (i = 0; i < progp->pg_nvers; i++) {
386 if (progp->pg_vers[i] == NULL)
387 continue;
388 if (progp->pg_vers[i]->vs_hidden == 0)
389 return 1;
390 }
391 }
392
393 return 0;
394}
395
396int svc_bind(struct svc_serv *serv, struct net *net)
397{
398 if (!svc_uses_rpcbind(serv))
399 return 0;
400 return svc_rpcb_setup(serv, net);
401}
402EXPORT_SYMBOL_GPL(svc_bind);
403
404/*
405 * Create an RPC service
406 */
407static struct svc_serv *
408__svc_create(struct svc_program *prog, unsigned int bufsize, int npools,
409 struct svc_serv_ops *ops)
410{
411 struct svc_serv *serv;
412 unsigned int vers;
413 unsigned int xdrsize;
414 unsigned int i;
415
416 if (!(serv = kzalloc(sizeof(*serv), GFP_KERNEL)))
417 return NULL;
418 serv->sv_name = prog->pg_name;
419 serv->sv_program = prog;
420 serv->sv_nrthreads = 1;
421 serv->sv_stats = prog->pg_stats;
422 if (bufsize > RPCSVC_MAXPAYLOAD)
423 bufsize = RPCSVC_MAXPAYLOAD;
424 serv->sv_max_payload = bufsize? bufsize : 4096;
425 serv->sv_max_mesg = roundup(serv->sv_max_payload + PAGE_SIZE, PAGE_SIZE);
426 serv->sv_ops = ops;
427 xdrsize = 0;
428 while (prog) {
429 prog->pg_lovers = prog->pg_nvers-1;
430 for (vers=0; vers<prog->pg_nvers ; vers++)
431 if (prog->pg_vers[vers]) {
432 prog->pg_hivers = vers;
433 if (prog->pg_lovers > vers)
434 prog->pg_lovers = vers;
435 if (prog->pg_vers[vers]->vs_xdrsize > xdrsize)
436 xdrsize = prog->pg_vers[vers]->vs_xdrsize;
437 }
438 prog = prog->pg_next;
439 }
440 serv->sv_xdrsize = xdrsize;
441 INIT_LIST_HEAD(&serv->sv_tempsocks);
442 INIT_LIST_HEAD(&serv->sv_permsocks);
443 init_timer(&serv->sv_temptimer);
444 spin_lock_init(&serv->sv_lock);
445
446 serv->sv_nrpools = npools;
447 serv->sv_pools =
448 kcalloc(serv->sv_nrpools, sizeof(struct svc_pool),
449 GFP_KERNEL);
450 if (!serv->sv_pools) {
451 kfree(serv);
452 return NULL;
453 }
454
455 for (i = 0; i < serv->sv_nrpools; i++) {
456 struct svc_pool *pool = &serv->sv_pools[i];
457
458 dprintk("svc: initialising pool %u for %s\n",
459 i, serv->sv_name);
460
461 pool->sp_id = i;
462 INIT_LIST_HEAD(&pool->sp_sockets);
463 INIT_LIST_HEAD(&pool->sp_all_threads);
464 spin_lock_init(&pool->sp_lock);
465 }
466
467 return serv;
468}
469
470struct svc_serv *
471svc_create(struct svc_program *prog, unsigned int bufsize,
472 struct svc_serv_ops *ops)
473{
474 return __svc_create(prog, bufsize, /*npools*/1, ops);
475}
476EXPORT_SYMBOL_GPL(svc_create);
477
478struct svc_serv *
479svc_create_pooled(struct svc_program *prog, unsigned int bufsize,
480 struct svc_serv_ops *ops)
481{
482 struct svc_serv *serv;
483 unsigned int npools = svc_pool_map_get();
484
485 serv = __svc_create(prog, bufsize, npools, ops);
486 if (!serv)
487 goto out_err;
488 return serv;
489out_err:
490 svc_pool_map_put();
491 return NULL;
492}
493EXPORT_SYMBOL_GPL(svc_create_pooled);
494
495void svc_shutdown_net(struct svc_serv *serv, struct net *net)
496{
497 svc_close_net(serv, net);
498
499 if (serv->sv_ops->svo_shutdown)
500 serv->sv_ops->svo_shutdown(serv, net);
501}
502EXPORT_SYMBOL_GPL(svc_shutdown_net);
503
504/*
505 * Destroy an RPC service. Should be called with appropriate locking to
506 * protect the sv_nrthreads, sv_permsocks and sv_tempsocks.
507 */
508void
509svc_destroy(struct svc_serv *serv)
510{
511 dprintk("svc: svc_destroy(%s, %d)\n",
512 serv->sv_program->pg_name,
513 serv->sv_nrthreads);
514
515 if (serv->sv_nrthreads) {
516 if (--(serv->sv_nrthreads) != 0) {
517 svc_sock_update_bufs(serv);
518 return;
519 }
520 } else
521 printk("svc_destroy: no threads for serv=%p!\n", serv);
522
523 del_timer_sync(&serv->sv_temptimer);
524
525 /*
526 * The last user is gone and thus all sockets have to be destroyed to
527 * the point. Check this.
528 */
529 BUG_ON(!list_empty(&serv->sv_permsocks));
530 BUG_ON(!list_empty(&serv->sv_tempsocks));
531
532 cache_clean_deferred(serv);
533
534 if (svc_serv_is_pooled(serv))
535 svc_pool_map_put();
536
537 kfree(serv->sv_pools);
538 kfree(serv);
539}
540EXPORT_SYMBOL_GPL(svc_destroy);
541
542/*
543 * Allocate an RPC server's buffer space.
544 * We allocate pages and place them in rq_argpages.
545 */
546static int
547svc_init_buffer(struct svc_rqst *rqstp, unsigned int size, int node)
548{
549 unsigned int pages, arghi;
550
551 /* bc_xprt uses fore channel allocated buffers */
552 if (svc_is_backchannel(rqstp))
553 return 1;
554
555 pages = size / PAGE_SIZE + 1; /* extra page as we hold both request and reply.
556 * We assume one is at most one page
557 */
558 arghi = 0;
559 WARN_ON_ONCE(pages > RPCSVC_MAXPAGES);
560 if (pages > RPCSVC_MAXPAGES)
561 pages = RPCSVC_MAXPAGES;
562 while (pages) {
563 struct page *p = alloc_pages_node(node, GFP_KERNEL, 0);
564 if (!p)
565 break;
566 rqstp->rq_pages[arghi++] = p;
567 pages--;
568 }
569 return pages == 0;
570}
571
572/*
573 * Release an RPC server buffer
574 */
575static void
576svc_release_buffer(struct svc_rqst *rqstp)
577{
578 unsigned int i;
579
580 for (i = 0; i < ARRAY_SIZE(rqstp->rq_pages); i++)
581 if (rqstp->rq_pages[i])
582 put_page(rqstp->rq_pages[i]);
583}
584
585struct svc_rqst *
586svc_rqst_alloc(struct svc_serv *serv, struct svc_pool *pool, int node)
587{
588 struct svc_rqst *rqstp;
589
590 rqstp = kzalloc_node(sizeof(*rqstp), GFP_KERNEL, node);
591 if (!rqstp)
592 return rqstp;
593
594 __set_bit(RQ_BUSY, &rqstp->rq_flags);
595 spin_lock_init(&rqstp->rq_lock);
596 rqstp->rq_server = serv;
597 rqstp->rq_pool = pool;
598
599 rqstp->rq_argp = kmalloc_node(serv->sv_xdrsize, GFP_KERNEL, node);
600 if (!rqstp->rq_argp)
601 goto out_enomem;
602
603 rqstp->rq_resp = kmalloc_node(serv->sv_xdrsize, GFP_KERNEL, node);
604 if (!rqstp->rq_resp)
605 goto out_enomem;
606
607 if (!svc_init_buffer(rqstp, serv->sv_max_mesg, node))
608 goto out_enomem;
609
610 return rqstp;
611out_enomem:
612 svc_rqst_free(rqstp);
613 return NULL;
614}
615EXPORT_SYMBOL_GPL(svc_rqst_alloc);
616
617struct svc_rqst *
618svc_prepare_thread(struct svc_serv *serv, struct svc_pool *pool, int node)
619{
620 struct svc_rqst *rqstp;
621
622 rqstp = svc_rqst_alloc(serv, pool, node);
623 if (!rqstp)
624 return ERR_PTR(-ENOMEM);
625
626 serv->sv_nrthreads++;
627 spin_lock_bh(&pool->sp_lock);
628 pool->sp_nrthreads++;
629 list_add_rcu(&rqstp->rq_all, &pool->sp_all_threads);
630 spin_unlock_bh(&pool->sp_lock);
631 return rqstp;
632}
633EXPORT_SYMBOL_GPL(svc_prepare_thread);
634
635/*
636 * Choose a pool in which to create a new thread, for svc_set_num_threads
637 */
638static inline struct svc_pool *
639choose_pool(struct svc_serv *serv, struct svc_pool *pool, unsigned int *state)
640{
641 if (pool != NULL)
642 return pool;
643
644 return &serv->sv_pools[(*state)++ % serv->sv_nrpools];
645}
646
647/*
648 * Choose a thread to kill, for svc_set_num_threads
649 */
650static inline struct task_struct *
651choose_victim(struct svc_serv *serv, struct svc_pool *pool, unsigned int *state)
652{
653 unsigned int i;
654 struct task_struct *task = NULL;
655
656 if (pool != NULL) {
657 spin_lock_bh(&pool->sp_lock);
658 } else {
659 /* choose a pool in round-robin fashion */
660 for (i = 0; i < serv->sv_nrpools; i++) {
661 pool = &serv->sv_pools[--(*state) % serv->sv_nrpools];
662 spin_lock_bh(&pool->sp_lock);
663 if (!list_empty(&pool->sp_all_threads))
664 goto found_pool;
665 spin_unlock_bh(&pool->sp_lock);
666 }
667 return NULL;
668 }
669
670found_pool:
671 if (!list_empty(&pool->sp_all_threads)) {
672 struct svc_rqst *rqstp;
673
674 /*
675 * Remove from the pool->sp_all_threads list
676 * so we don't try to kill it again.
677 */
678 rqstp = list_entry(pool->sp_all_threads.next, struct svc_rqst, rq_all);
679 set_bit(RQ_VICTIM, &rqstp->rq_flags);
680 list_del_rcu(&rqstp->rq_all);
681 task = rqstp->rq_task;
682 }
683 spin_unlock_bh(&pool->sp_lock);
684
685 return task;
686}
687
688/*
689 * Create or destroy enough new threads to make the number
690 * of threads the given number. If `pool' is non-NULL, applies
691 * only to threads in that pool, otherwise round-robins between
692 * all pools. Caller must ensure that mutual exclusion between this and
693 * server startup or shutdown.
694 *
695 * Destroying threads relies on the service threads filling in
696 * rqstp->rq_task, which only the nfs ones do. Assumes the serv
697 * has been created using svc_create_pooled().
698 *
699 * Based on code that used to be in nfsd_svc() but tweaked
700 * to be pool-aware.
701 */
702int
703svc_set_num_threads(struct svc_serv *serv, struct svc_pool *pool, int nrservs)
704{
705 struct svc_rqst *rqstp;
706 struct task_struct *task;
707 struct svc_pool *chosen_pool;
708 int error = 0;
709 unsigned int state = serv->sv_nrthreads-1;
710 int node;
711
712 if (pool == NULL) {
713 /* The -1 assumes caller has done a svc_get() */
714 nrservs -= (serv->sv_nrthreads-1);
715 } else {
716 spin_lock_bh(&pool->sp_lock);
717 nrservs -= pool->sp_nrthreads;
718 spin_unlock_bh(&pool->sp_lock);
719 }
720
721 /* create new threads */
722 while (nrservs > 0) {
723 nrservs--;
724 chosen_pool = choose_pool(serv, pool, &state);
725
726 node = svc_pool_map_get_node(chosen_pool->sp_id);
727 rqstp = svc_prepare_thread(serv, chosen_pool, node);
728 if (IS_ERR(rqstp)) {
729 error = PTR_ERR(rqstp);
730 break;
731 }
732
733 __module_get(serv->sv_ops->svo_module);
734 task = kthread_create_on_node(serv->sv_ops->svo_function, rqstp,
735 node, "%s", serv->sv_name);
736 if (IS_ERR(task)) {
737 error = PTR_ERR(task);
738 module_put(serv->sv_ops->svo_module);
739 svc_exit_thread(rqstp);
740 break;
741 }
742
743 rqstp->rq_task = task;
744 if (serv->sv_nrpools > 1)
745 svc_pool_map_set_cpumask(task, chosen_pool->sp_id);
746
747 svc_sock_update_bufs(serv);
748 wake_up_process(task);
749 }
750 /* destroy old threads */
751 while (nrservs < 0 &&
752 (task = choose_victim(serv, pool, &state)) != NULL) {
753 send_sig(SIGINT, task, 1);
754 nrservs++;
755 }
756
757 return error;
758}
759EXPORT_SYMBOL_GPL(svc_set_num_threads);
760
761/*
762 * Called from a server thread as it's exiting. Caller must hold the "service
763 * mutex" for the service.
764 */
765void
766svc_rqst_free(struct svc_rqst *rqstp)
767{
768 svc_release_buffer(rqstp);
769 kfree(rqstp->rq_resp);
770 kfree(rqstp->rq_argp);
771 kfree(rqstp->rq_auth_data);
772 kfree_rcu(rqstp, rq_rcu_head);
773}
774EXPORT_SYMBOL_GPL(svc_rqst_free);
775
776void
777svc_exit_thread(struct svc_rqst *rqstp)
778{
779 struct svc_serv *serv = rqstp->rq_server;
780 struct svc_pool *pool = rqstp->rq_pool;
781
782 spin_lock_bh(&pool->sp_lock);
783 pool->sp_nrthreads--;
784 if (!test_and_set_bit(RQ_VICTIM, &rqstp->rq_flags))
785 list_del_rcu(&rqstp->rq_all);
786 spin_unlock_bh(&pool->sp_lock);
787
788 svc_rqst_free(rqstp);
789
790 /* Release the server */
791 if (serv)
792 svc_destroy(serv);
793}
794EXPORT_SYMBOL_GPL(svc_exit_thread);
795
796/*
797 * Register an "inet" protocol family netid with the local
798 * rpcbind daemon via an rpcbind v4 SET request.
799 *
800 * No netconfig infrastructure is available in the kernel, so
801 * we map IP_ protocol numbers to netids by hand.
802 *
803 * Returns zero on success; a negative errno value is returned
804 * if any error occurs.
805 */
806static int __svc_rpcb_register4(struct net *net, const u32 program,
807 const u32 version,
808 const unsigned short protocol,
809 const unsigned short port)
810{
811 const struct sockaddr_in sin = {
812 .sin_family = AF_INET,
813 .sin_addr.s_addr = htonl(INADDR_ANY),
814 .sin_port = htons(port),
815 };
816 const char *netid;
817 int error;
818
819 switch (protocol) {
820 case IPPROTO_UDP:
821 netid = RPCBIND_NETID_UDP;
822 break;
823 case IPPROTO_TCP:
824 netid = RPCBIND_NETID_TCP;
825 break;
826 default:
827 return -ENOPROTOOPT;
828 }
829
830 error = rpcb_v4_register(net, program, version,
831 (const struct sockaddr *)&sin, netid);
832
833 /*
834 * User space didn't support rpcbind v4, so retry this
835 * registration request with the legacy rpcbind v2 protocol.
836 */
837 if (error == -EPROTONOSUPPORT)
838 error = rpcb_register(net, program, version, protocol, port);
839
840 return error;
841}
842
843#if IS_ENABLED(CONFIG_IPV6)
844/*
845 * Register an "inet6" protocol family netid with the local
846 * rpcbind daemon via an rpcbind v4 SET request.
847 *
848 * No netconfig infrastructure is available in the kernel, so
849 * we map IP_ protocol numbers to netids by hand.
850 *
851 * Returns zero on success; a negative errno value is returned
852 * if any error occurs.
853 */
854static int __svc_rpcb_register6(struct net *net, const u32 program,
855 const u32 version,
856 const unsigned short protocol,
857 const unsigned short port)
858{
859 const struct sockaddr_in6 sin6 = {
860 .sin6_family = AF_INET6,
861 .sin6_addr = IN6ADDR_ANY_INIT,
862 .sin6_port = htons(port),
863 };
864 const char *netid;
865 int error;
866
867 switch (protocol) {
868 case IPPROTO_UDP:
869 netid = RPCBIND_NETID_UDP6;
870 break;
871 case IPPROTO_TCP:
872 netid = RPCBIND_NETID_TCP6;
873 break;
874 default:
875 return -ENOPROTOOPT;
876 }
877
878 error = rpcb_v4_register(net, program, version,
879 (const struct sockaddr *)&sin6, netid);
880
881 /*
882 * User space didn't support rpcbind version 4, so we won't
883 * use a PF_INET6 listener.
884 */
885 if (error == -EPROTONOSUPPORT)
886 error = -EAFNOSUPPORT;
887
888 return error;
889}
890#endif /* IS_ENABLED(CONFIG_IPV6) */
891
892/*
893 * Register a kernel RPC service via rpcbind version 4.
894 *
895 * Returns zero on success; a negative errno value is returned
896 * if any error occurs.
897 */
898static int __svc_register(struct net *net, const char *progname,
899 const u32 program, const u32 version,
900 const int family,
901 const unsigned short protocol,
902 const unsigned short port)
903{
904 int error = -EAFNOSUPPORT;
905
906 switch (family) {
907 case PF_INET:
908 error = __svc_rpcb_register4(net, program, version,
909 protocol, port);
910 break;
911#if IS_ENABLED(CONFIG_IPV6)
912 case PF_INET6:
913 error = __svc_rpcb_register6(net, program, version,
914 protocol, port);
915#endif
916 }
917
918 return error;
919}
920
921/**
922 * svc_register - register an RPC service with the local portmapper
923 * @serv: svc_serv struct for the service to register
924 * @net: net namespace for the service to register
925 * @family: protocol family of service's listener socket
926 * @proto: transport protocol number to advertise
927 * @port: port to advertise
928 *
929 * Service is registered for any address in the passed-in protocol family
930 */
931int svc_register(const struct svc_serv *serv, struct net *net,
932 const int family, const unsigned short proto,
933 const unsigned short port)
934{
935 struct svc_program *progp;
936 struct svc_version *vers;
937 unsigned int i;
938 int error = 0;
939
940 WARN_ON_ONCE(proto == 0 && port == 0);
941 if (proto == 0 && port == 0)
942 return -EINVAL;
943
944 for (progp = serv->sv_program; progp; progp = progp->pg_next) {
945 for (i = 0; i < progp->pg_nvers; i++) {
946 vers = progp->pg_vers[i];
947 if (vers == NULL)
948 continue;
949
950 dprintk("svc: svc_register(%sv%d, %s, %u, %u)%s\n",
951 progp->pg_name,
952 i,
953 proto == IPPROTO_UDP? "udp" : "tcp",
954 port,
955 family,
956 vers->vs_hidden ?
957 " (but not telling portmap)" : "");
958
959 if (vers->vs_hidden)
960 continue;
961
962 error = __svc_register(net, progp->pg_name, progp->pg_prog,
963 i, family, proto, port);
964
965 if (vers->vs_rpcb_optnl) {
966 error = 0;
967 continue;
968 }
969
970 if (error < 0) {
971 printk(KERN_WARNING "svc: failed to register "
972 "%sv%u RPC service (errno %d).\n",
973 progp->pg_name, i, -error);
974 break;
975 }
976 }
977 }
978
979 return error;
980}
981
982/*
983 * If user space is running rpcbind, it should take the v4 UNSET
984 * and clear everything for this [program, version]. If user space
985 * is running portmap, it will reject the v4 UNSET, but won't have
986 * any "inet6" entries anyway. So a PMAP_UNSET should be sufficient
987 * in this case to clear all existing entries for [program, version].
988 */
989static void __svc_unregister(struct net *net, const u32 program, const u32 version,
990 const char *progname)
991{
992 int error;
993
994 error = rpcb_v4_register(net, program, version, NULL, "");
995
996 /*
997 * User space didn't support rpcbind v4, so retry this
998 * request with the legacy rpcbind v2 protocol.
999 */
1000 if (error == -EPROTONOSUPPORT)
1001 error = rpcb_register(net, program, version, 0, 0);
1002
1003 dprintk("svc: %s(%sv%u), error %d\n",
1004 __func__, progname, version, error);
1005}
1006
1007/*
1008 * All netids, bind addresses and ports registered for [program, version]
1009 * are removed from the local rpcbind database (if the service is not
1010 * hidden) to make way for a new instance of the service.
1011 *
1012 * The result of unregistration is reported via dprintk for those who want
1013 * verification of the result, but is otherwise not important.
1014 */
1015static void svc_unregister(const struct svc_serv *serv, struct net *net)
1016{
1017 struct svc_program *progp;
1018 unsigned long flags;
1019 unsigned int i;
1020
1021 clear_thread_flag(TIF_SIGPENDING);
1022
1023 for (progp = serv->sv_program; progp; progp = progp->pg_next) {
1024 for (i = 0; i < progp->pg_nvers; i++) {
1025 if (progp->pg_vers[i] == NULL)
1026 continue;
1027 if (progp->pg_vers[i]->vs_hidden)
1028 continue;
1029
1030 dprintk("svc: attempting to unregister %sv%u\n",
1031 progp->pg_name, i);
1032 __svc_unregister(net, progp->pg_prog, i, progp->pg_name);
1033 }
1034 }
1035
1036 spin_lock_irqsave(¤t->sighand->siglock, flags);
1037 recalc_sigpending();
1038 spin_unlock_irqrestore(¤t->sighand->siglock, flags);
1039}
1040
1041/*
1042 * dprintk the given error with the address of the client that caused it.
1043 */
1044#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
1045static __printf(2, 3)
1046void svc_printk(struct svc_rqst *rqstp, const char *fmt, ...)
1047{
1048 struct va_format vaf;
1049 va_list args;
1050 char buf[RPC_MAX_ADDRBUFLEN];
1051
1052 va_start(args, fmt);
1053
1054 vaf.fmt = fmt;
1055 vaf.va = &args;
1056
1057 dprintk("svc: %s: %pV", svc_print_addr(rqstp, buf, sizeof(buf)), &vaf);
1058
1059 va_end(args);
1060}
1061#else
1062static __printf(2,3) void svc_printk(struct svc_rqst *rqstp, const char *fmt, ...) {}
1063#endif
1064
1065/*
1066 * Common routine for processing the RPC request.
1067 */
1068static int
1069svc_process_common(struct svc_rqst *rqstp, struct kvec *argv, struct kvec *resv)
1070{
1071 struct svc_program *progp;
1072 struct svc_version *versp = NULL; /* compiler food */
1073 struct svc_procedure *procp = NULL;
1074 struct svc_serv *serv = rqstp->rq_server;
1075 kxdrproc_t xdr;
1076 __be32 *statp;
1077 u32 prog, vers, proc;
1078 __be32 auth_stat, rpc_stat;
1079 int auth_res;
1080 __be32 *reply_statp;
1081
1082 rpc_stat = rpc_success;
1083
1084 if (argv->iov_len < 6*4)
1085 goto err_short_len;
1086
1087 /* Will be turned off only in gss privacy case: */
1088 set_bit(RQ_SPLICE_OK, &rqstp->rq_flags);
1089 /* Will be turned off only when NFSv4 Sessions are used */
1090 set_bit(RQ_USEDEFERRAL, &rqstp->rq_flags);
1091 clear_bit(RQ_DROPME, &rqstp->rq_flags);
1092
1093 /* Setup reply header */
1094 rqstp->rq_xprt->xpt_ops->xpo_prep_reply_hdr(rqstp);
1095
1096 svc_putu32(resv, rqstp->rq_xid);
1097
1098 vers = svc_getnl(argv);
1099
1100 /* First words of reply: */
1101 svc_putnl(resv, 1); /* REPLY */
1102
1103 if (vers != 2) /* RPC version number */
1104 goto err_bad_rpc;
1105
1106 /* Save position in case we later decide to reject: */
1107 reply_statp = resv->iov_base + resv->iov_len;
1108
1109 svc_putnl(resv, 0); /* ACCEPT */
1110
1111 rqstp->rq_prog = prog = svc_getnl(argv); /* program number */
1112 rqstp->rq_vers = vers = svc_getnl(argv); /* version number */
1113 rqstp->rq_proc = proc = svc_getnl(argv); /* procedure number */
1114
1115 for (progp = serv->sv_program; progp; progp = progp->pg_next)
1116 if (prog == progp->pg_prog)
1117 break;
1118
1119 /*
1120 * Decode auth data, and add verifier to reply buffer.
1121 * We do this before anything else in order to get a decent
1122 * auth verifier.
1123 */
1124 auth_res = svc_authenticate(rqstp, &auth_stat);
1125 /* Also give the program a chance to reject this call: */
1126 if (auth_res == SVC_OK && progp) {
1127 auth_stat = rpc_autherr_badcred;
1128 auth_res = progp->pg_authenticate(rqstp);
1129 }
1130 switch (auth_res) {
1131 case SVC_OK:
1132 break;
1133 case SVC_GARBAGE:
1134 goto err_garbage;
1135 case SVC_SYSERR:
1136 rpc_stat = rpc_system_err;
1137 goto err_bad;
1138 case SVC_DENIED:
1139 goto err_bad_auth;
1140 case SVC_CLOSE:
1141 if (test_bit(XPT_TEMP, &rqstp->rq_xprt->xpt_flags))
1142 svc_close_xprt(rqstp->rq_xprt);
1143 case SVC_DROP:
1144 goto dropit;
1145 case SVC_COMPLETE:
1146 goto sendit;
1147 }
1148
1149 if (progp == NULL)
1150 goto err_bad_prog;
1151
1152 if (vers >= progp->pg_nvers ||
1153 !(versp = progp->pg_vers[vers]))
1154 goto err_bad_vers;
1155
1156 procp = versp->vs_proc + proc;
1157 if (proc >= versp->vs_nproc || !procp->pc_func)
1158 goto err_bad_proc;
1159 rqstp->rq_procinfo = procp;
1160
1161 /* Syntactic check complete */
1162 serv->sv_stats->rpccnt++;
1163
1164 /* Build the reply header. */
1165 statp = resv->iov_base +resv->iov_len;
1166 svc_putnl(resv, RPC_SUCCESS);
1167
1168 /* Bump per-procedure stats counter */
1169 procp->pc_count++;
1170
1171 /* Initialize storage for argp and resp */
1172 memset(rqstp->rq_argp, 0, procp->pc_argsize);
1173 memset(rqstp->rq_resp, 0, procp->pc_ressize);
1174
1175 /* un-reserve some of the out-queue now that we have a
1176 * better idea of reply size
1177 */
1178 if (procp->pc_xdrressize)
1179 svc_reserve_auth(rqstp, procp->pc_xdrressize<<2);
1180
1181 /* Call the function that processes the request. */
1182 if (!versp->vs_dispatch) {
1183 /* Decode arguments */
1184 xdr = procp->pc_decode;
1185 if (xdr && !xdr(rqstp, argv->iov_base, rqstp->rq_argp))
1186 goto err_garbage;
1187
1188 *statp = procp->pc_func(rqstp, rqstp->rq_argp, rqstp->rq_resp);
1189
1190 /* Encode reply */
1191 if (test_bit(RQ_DROPME, &rqstp->rq_flags)) {
1192 if (procp->pc_release)
1193 procp->pc_release(rqstp, NULL, rqstp->rq_resp);
1194 goto dropit;
1195 }
1196 if (*statp == rpc_success &&
1197 (xdr = procp->pc_encode) &&
1198 !xdr(rqstp, resv->iov_base+resv->iov_len, rqstp->rq_resp)) {
1199 dprintk("svc: failed to encode reply\n");
1200 /* serv->sv_stats->rpcsystemerr++; */
1201 *statp = rpc_system_err;
1202 }
1203 } else {
1204 dprintk("svc: calling dispatcher\n");
1205 if (!versp->vs_dispatch(rqstp, statp)) {
1206 /* Release reply info */
1207 if (procp->pc_release)
1208 procp->pc_release(rqstp, NULL, rqstp->rq_resp);
1209 goto dropit;
1210 }
1211 }
1212
1213 /* Check RPC status result */
1214 if (*statp != rpc_success)
1215 resv->iov_len = ((void*)statp) - resv->iov_base + 4;
1216
1217 /* Release reply info */
1218 if (procp->pc_release)
1219 procp->pc_release(rqstp, NULL, rqstp->rq_resp);
1220
1221 if (procp->pc_encode == NULL)
1222 goto dropit;
1223
1224 sendit:
1225 if (svc_authorise(rqstp))
1226 goto dropit;
1227 return 1; /* Caller can now send it */
1228
1229 dropit:
1230 svc_authorise(rqstp); /* doesn't hurt to call this twice */
1231 dprintk("svc: svc_process dropit\n");
1232 return 0;
1233
1234err_short_len:
1235 svc_printk(rqstp, "short len %Zd, dropping request\n",
1236 argv->iov_len);
1237
1238 goto dropit; /* drop request */
1239
1240err_bad_rpc:
1241 serv->sv_stats->rpcbadfmt++;
1242 svc_putnl(resv, 1); /* REJECT */
1243 svc_putnl(resv, 0); /* RPC_MISMATCH */
1244 svc_putnl(resv, 2); /* Only RPCv2 supported */
1245 svc_putnl(resv, 2);
1246 goto sendit;
1247
1248err_bad_auth:
1249 dprintk("svc: authentication failed (%d)\n", ntohl(auth_stat));
1250 serv->sv_stats->rpcbadauth++;
1251 /* Restore write pointer to location of accept status: */
1252 xdr_ressize_check(rqstp, reply_statp);
1253 svc_putnl(resv, 1); /* REJECT */
1254 svc_putnl(resv, 1); /* AUTH_ERROR */
1255 svc_putnl(resv, ntohl(auth_stat)); /* status */
1256 goto sendit;
1257
1258err_bad_prog:
1259 dprintk("svc: unknown program %d\n", prog);
1260 serv->sv_stats->rpcbadfmt++;
1261 svc_putnl(resv, RPC_PROG_UNAVAIL);
1262 goto sendit;
1263
1264err_bad_vers:
1265 svc_printk(rqstp, "unknown version (%d for prog %d, %s)\n",
1266 vers, prog, progp->pg_name);
1267
1268 serv->sv_stats->rpcbadfmt++;
1269 svc_putnl(resv, RPC_PROG_MISMATCH);
1270 svc_putnl(resv, progp->pg_lovers);
1271 svc_putnl(resv, progp->pg_hivers);
1272 goto sendit;
1273
1274err_bad_proc:
1275 svc_printk(rqstp, "unknown procedure (%d)\n", proc);
1276
1277 serv->sv_stats->rpcbadfmt++;
1278 svc_putnl(resv, RPC_PROC_UNAVAIL);
1279 goto sendit;
1280
1281err_garbage:
1282 svc_printk(rqstp, "failed to decode args\n");
1283
1284 rpc_stat = rpc_garbage_args;
1285err_bad:
1286 serv->sv_stats->rpcbadfmt++;
1287 svc_putnl(resv, ntohl(rpc_stat));
1288 goto sendit;
1289}
1290
1291/*
1292 * Process the RPC request.
1293 */
1294int
1295svc_process(struct svc_rqst *rqstp)
1296{
1297 struct kvec *argv = &rqstp->rq_arg.head[0];
1298 struct kvec *resv = &rqstp->rq_res.head[0];
1299 struct svc_serv *serv = rqstp->rq_server;
1300 u32 dir;
1301
1302 /*
1303 * Setup response xdr_buf.
1304 * Initially it has just one page
1305 */
1306 rqstp->rq_next_page = &rqstp->rq_respages[1];
1307 resv->iov_base = page_address(rqstp->rq_respages[0]);
1308 resv->iov_len = 0;
1309 rqstp->rq_res.pages = rqstp->rq_respages + 1;
1310 rqstp->rq_res.len = 0;
1311 rqstp->rq_res.page_base = 0;
1312 rqstp->rq_res.page_len = 0;
1313 rqstp->rq_res.buflen = PAGE_SIZE;
1314 rqstp->rq_res.tail[0].iov_base = NULL;
1315 rqstp->rq_res.tail[0].iov_len = 0;
1316
1317 dir = svc_getnl(argv);
1318 if (dir != 0) {
1319 /* direction != CALL */
1320 svc_printk(rqstp, "bad direction %d, dropping request\n", dir);
1321 serv->sv_stats->rpcbadfmt++;
1322 goto out_drop;
1323 }
1324
1325 /* Returns 1 for send, 0 for drop */
1326 if (likely(svc_process_common(rqstp, argv, resv))) {
1327 int ret = svc_send(rqstp);
1328
1329 trace_svc_process(rqstp, ret);
1330 return ret;
1331 }
1332out_drop:
1333 trace_svc_process(rqstp, 0);
1334 svc_drop(rqstp);
1335 return 0;
1336}
1337EXPORT_SYMBOL_GPL(svc_process);
1338
1339#if defined(CONFIG_SUNRPC_BACKCHANNEL)
1340/*
1341 * Process a backchannel RPC request that arrived over an existing
1342 * outbound connection
1343 */
1344int
1345bc_svc_process(struct svc_serv *serv, struct rpc_rqst *req,
1346 struct svc_rqst *rqstp)
1347{
1348 struct kvec *argv = &rqstp->rq_arg.head[0];
1349 struct kvec *resv = &rqstp->rq_res.head[0];
1350 struct rpc_task *task;
1351 int proc_error;
1352 int error;
1353
1354 dprintk("svc: %s(%p)\n", __func__, req);
1355
1356 /* Build the svc_rqst used by the common processing routine */
1357 rqstp->rq_xprt = serv->sv_bc_xprt;
1358 rqstp->rq_xid = req->rq_xid;
1359 rqstp->rq_prot = req->rq_xprt->prot;
1360 rqstp->rq_server = serv;
1361
1362 rqstp->rq_addrlen = sizeof(req->rq_xprt->addr);
1363 memcpy(&rqstp->rq_addr, &req->rq_xprt->addr, rqstp->rq_addrlen);
1364 memcpy(&rqstp->rq_arg, &req->rq_rcv_buf, sizeof(rqstp->rq_arg));
1365 memcpy(&rqstp->rq_res, &req->rq_snd_buf, sizeof(rqstp->rq_res));
1366
1367 /* Adjust the argument buffer length */
1368 rqstp->rq_arg.len = req->rq_private_buf.len;
1369 if (rqstp->rq_arg.len <= rqstp->rq_arg.head[0].iov_len) {
1370 rqstp->rq_arg.head[0].iov_len = rqstp->rq_arg.len;
1371 rqstp->rq_arg.page_len = 0;
1372 } else if (rqstp->rq_arg.len <= rqstp->rq_arg.head[0].iov_len +
1373 rqstp->rq_arg.page_len)
1374 rqstp->rq_arg.page_len = rqstp->rq_arg.len -
1375 rqstp->rq_arg.head[0].iov_len;
1376 else
1377 rqstp->rq_arg.len = rqstp->rq_arg.head[0].iov_len +
1378 rqstp->rq_arg.page_len;
1379
1380 /* reset result send buffer "put" position */
1381 resv->iov_len = 0;
1382
1383 /*
1384 * Skip the next two words because they've already been
1385 * processed in the transport
1386 */
1387 svc_getu32(argv); /* XID */
1388 svc_getnl(argv); /* CALLDIR */
1389
1390 /* Parse and execute the bc call */
1391 proc_error = svc_process_common(rqstp, argv, resv);
1392
1393 atomic_inc(&req->rq_xprt->bc_free_slots);
1394 if (!proc_error) {
1395 /* Processing error: drop the request */
1396 xprt_free_bc_request(req);
1397 return 0;
1398 }
1399
1400 /* Finally, send the reply synchronously */
1401 memcpy(&req->rq_snd_buf, &rqstp->rq_res, sizeof(req->rq_snd_buf));
1402 task = rpc_run_bc_task(req);
1403 if (IS_ERR(task)) {
1404 error = PTR_ERR(task);
1405 goto out;
1406 }
1407
1408 WARN_ON_ONCE(atomic_read(&task->tk_count) != 1);
1409 error = task->tk_status;
1410 rpc_put_task(task);
1411
1412out:
1413 dprintk("svc: %s(), error=%d\n", __func__, error);
1414 return error;
1415}
1416EXPORT_SYMBOL_GPL(bc_svc_process);
1417#endif /* CONFIG_SUNRPC_BACKCHANNEL */
1418
1419/*
1420 * Return (transport-specific) limit on the rpc payload.
1421 */
1422u32 svc_max_payload(const struct svc_rqst *rqstp)
1423{
1424 u32 max = rqstp->rq_xprt->xpt_class->xcl_max_payload;
1425
1426 if (rqstp->rq_server->sv_max_payload < max)
1427 max = rqstp->rq_server->sv_max_payload;
1428 return max;
1429}
1430EXPORT_SYMBOL_GPL(svc_max_payload);
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
24#include <linux/sunrpc/types.h>
25#include <linux/sunrpc/xdr.h>
26#include <linux/sunrpc/stats.h>
27#include <linux/sunrpc/svcsock.h>
28#include <linux/sunrpc/clnt.h>
29#include <linux/sunrpc/bc_xprt.h>
30
31#include <trace/events/sunrpc.h>
32
33#define RPCDBG_FACILITY RPCDBG_SVCDSP
34
35static void svc_unregister(const struct svc_serv *serv, struct net *net);
36
37#define svc_serv_is_pooled(serv) ((serv)->sv_ops->svo_function)
38
39#define SVC_POOL_DEFAULT SVC_POOL_GLOBAL
40
41/*
42 * Structure for mapping cpus to pools and vice versa.
43 * Setup once during sunrpc initialisation.
44 */
45struct svc_pool_map svc_pool_map = {
46 .mode = SVC_POOL_DEFAULT
47};
48EXPORT_SYMBOL_GPL(svc_pool_map);
49
50static DEFINE_MUTEX(svc_pool_map_mutex);/* protects svc_pool_map.count only */
51
52static int
53param_set_pool_mode(const char *val, struct kernel_param *kp)
54{
55 int *ip = (int *)kp->arg;
56 struct svc_pool_map *m = &svc_pool_map;
57 int err;
58
59 mutex_lock(&svc_pool_map_mutex);
60
61 err = -EBUSY;
62 if (m->count)
63 goto out;
64
65 err = 0;
66 if (!strncmp(val, "auto", 4))
67 *ip = SVC_POOL_AUTO;
68 else if (!strncmp(val, "global", 6))
69 *ip = SVC_POOL_GLOBAL;
70 else if (!strncmp(val, "percpu", 6))
71 *ip = SVC_POOL_PERCPU;
72 else if (!strncmp(val, "pernode", 7))
73 *ip = SVC_POOL_PERNODE;
74 else
75 err = -EINVAL;
76
77out:
78 mutex_unlock(&svc_pool_map_mutex);
79 return err;
80}
81
82static int
83param_get_pool_mode(char *buf, struct kernel_param *kp)
84{
85 int *ip = (int *)kp->arg;
86
87 switch (*ip)
88 {
89 case SVC_POOL_AUTO:
90 return strlcpy(buf, "auto", 20);
91 case SVC_POOL_GLOBAL:
92 return strlcpy(buf, "global", 20);
93 case SVC_POOL_PERCPU:
94 return strlcpy(buf, "percpu", 20);
95 case SVC_POOL_PERNODE:
96 return strlcpy(buf, "pernode", 20);
97 default:
98 return sprintf(buf, "%d", *ip);
99 }
100}
101
102module_param_call(pool_mode, param_set_pool_mode, param_get_pool_mode,
103 &svc_pool_map.mode, 0644);
104
105/*
106 * Detect best pool mapping mode heuristically,
107 * according to the machine's topology.
108 */
109static int
110svc_pool_map_choose_mode(void)
111{
112 unsigned int node;
113
114 if (nr_online_nodes > 1) {
115 /*
116 * Actually have multiple NUMA nodes,
117 * so split pools on NUMA node boundaries
118 */
119 return SVC_POOL_PERNODE;
120 }
121
122 node = first_online_node;
123 if (nr_cpus_node(node) > 2) {
124 /*
125 * Non-trivial SMP, or CONFIG_NUMA on
126 * non-NUMA hardware, e.g. with a generic
127 * x86_64 kernel on Xeons. In this case we
128 * want to divide the pools on cpu boundaries.
129 */
130 return SVC_POOL_PERCPU;
131 }
132
133 /* default: one global pool */
134 return SVC_POOL_GLOBAL;
135}
136
137/*
138 * Allocate the to_pool[] and pool_to[] arrays.
139 * Returns 0 on success or an errno.
140 */
141static int
142svc_pool_map_alloc_arrays(struct svc_pool_map *m, unsigned int maxpools)
143{
144 m->to_pool = kcalloc(maxpools, sizeof(unsigned int), GFP_KERNEL);
145 if (!m->to_pool)
146 goto fail;
147 m->pool_to = kcalloc(maxpools, sizeof(unsigned int), GFP_KERNEL);
148 if (!m->pool_to)
149 goto fail_free;
150
151 return 0;
152
153fail_free:
154 kfree(m->to_pool);
155 m->to_pool = NULL;
156fail:
157 return -ENOMEM;
158}
159
160/*
161 * Initialise the pool map for SVC_POOL_PERCPU mode.
162 * Returns number of pools or <0 on error.
163 */
164static int
165svc_pool_map_init_percpu(struct svc_pool_map *m)
166{
167 unsigned int maxpools = nr_cpu_ids;
168 unsigned int pidx = 0;
169 unsigned int cpu;
170 int err;
171
172 err = svc_pool_map_alloc_arrays(m, maxpools);
173 if (err)
174 return err;
175
176 for_each_online_cpu(cpu) {
177 BUG_ON(pidx >= maxpools);
178 m->to_pool[cpu] = pidx;
179 m->pool_to[pidx] = cpu;
180 pidx++;
181 }
182 /* cpus brought online later all get mapped to pool0, sorry */
183
184 return pidx;
185};
186
187
188/*
189 * Initialise the pool map for SVC_POOL_PERNODE mode.
190 * Returns number of pools or <0 on error.
191 */
192static int
193svc_pool_map_init_pernode(struct svc_pool_map *m)
194{
195 unsigned int maxpools = nr_node_ids;
196 unsigned int pidx = 0;
197 unsigned int node;
198 int err;
199
200 err = svc_pool_map_alloc_arrays(m, maxpools);
201 if (err)
202 return err;
203
204 for_each_node_with_cpus(node) {
205 /* some architectures (e.g. SN2) have cpuless nodes */
206 BUG_ON(pidx > maxpools);
207 m->to_pool[node] = pidx;
208 m->pool_to[pidx] = node;
209 pidx++;
210 }
211 /* nodes brought online later all get mapped to pool0, sorry */
212
213 return pidx;
214}
215
216
217/*
218 * Add a reference to the global map of cpus to pools (and
219 * vice versa). Initialise the map if we're the first user.
220 * Returns the number of pools.
221 */
222unsigned int
223svc_pool_map_get(void)
224{
225 struct svc_pool_map *m = &svc_pool_map;
226 int npools = -1;
227
228 mutex_lock(&svc_pool_map_mutex);
229
230 if (m->count++) {
231 mutex_unlock(&svc_pool_map_mutex);
232 return m->npools;
233 }
234
235 if (m->mode == SVC_POOL_AUTO)
236 m->mode = svc_pool_map_choose_mode();
237
238 switch (m->mode) {
239 case SVC_POOL_PERCPU:
240 npools = svc_pool_map_init_percpu(m);
241 break;
242 case SVC_POOL_PERNODE:
243 npools = svc_pool_map_init_pernode(m);
244 break;
245 }
246
247 if (npools < 0) {
248 /* default, or memory allocation failure */
249 npools = 1;
250 m->mode = SVC_POOL_GLOBAL;
251 }
252 m->npools = npools;
253
254 mutex_unlock(&svc_pool_map_mutex);
255 return m->npools;
256}
257EXPORT_SYMBOL_GPL(svc_pool_map_get);
258
259/*
260 * Drop a reference to the global map of cpus to pools.
261 * When the last reference is dropped, the map data is
262 * freed; this allows the sysadmin to change the pool
263 * mode using the pool_mode module option without
264 * rebooting or re-loading sunrpc.ko.
265 */
266void
267svc_pool_map_put(void)
268{
269 struct svc_pool_map *m = &svc_pool_map;
270
271 mutex_lock(&svc_pool_map_mutex);
272
273 if (!--m->count) {
274 kfree(m->to_pool);
275 m->to_pool = NULL;
276 kfree(m->pool_to);
277 m->pool_to = NULL;
278 m->npools = 0;
279 }
280
281 mutex_unlock(&svc_pool_map_mutex);
282}
283EXPORT_SYMBOL_GPL(svc_pool_map_put);
284
285static int svc_pool_map_get_node(unsigned int pidx)
286{
287 const struct svc_pool_map *m = &svc_pool_map;
288
289 if (m->count) {
290 if (m->mode == SVC_POOL_PERCPU)
291 return cpu_to_node(m->pool_to[pidx]);
292 if (m->mode == SVC_POOL_PERNODE)
293 return m->pool_to[pidx];
294 }
295 return NUMA_NO_NODE;
296}
297/*
298 * Set the given thread's cpus_allowed mask so that it
299 * will only run on cpus in the given pool.
300 */
301static inline void
302svc_pool_map_set_cpumask(struct task_struct *task, unsigned int pidx)
303{
304 struct svc_pool_map *m = &svc_pool_map;
305 unsigned int node = m->pool_to[pidx];
306
307 /*
308 * The caller checks for sv_nrpools > 1, which
309 * implies that we've been initialized.
310 */
311 WARN_ON_ONCE(m->count == 0);
312 if (m->count == 0)
313 return;
314
315 switch (m->mode) {
316 case SVC_POOL_PERCPU:
317 {
318 set_cpus_allowed_ptr(task, cpumask_of(node));
319 break;
320 }
321 case SVC_POOL_PERNODE:
322 {
323 set_cpus_allowed_ptr(task, cpumask_of_node(node));
324 break;
325 }
326 }
327}
328
329/*
330 * Use the mapping mode to choose a pool for a given CPU.
331 * Used when enqueueing an incoming RPC. Always returns
332 * a non-NULL pool pointer.
333 */
334struct svc_pool *
335svc_pool_for_cpu(struct svc_serv *serv, int cpu)
336{
337 struct svc_pool_map *m = &svc_pool_map;
338 unsigned int pidx = 0;
339
340 /*
341 * An uninitialised map happens in a pure client when
342 * lockd is brought up, so silently treat it the
343 * same as SVC_POOL_GLOBAL.
344 */
345 if (svc_serv_is_pooled(serv)) {
346 switch (m->mode) {
347 case SVC_POOL_PERCPU:
348 pidx = m->to_pool[cpu];
349 break;
350 case SVC_POOL_PERNODE:
351 pidx = m->to_pool[cpu_to_node(cpu)];
352 break;
353 }
354 }
355 return &serv->sv_pools[pidx % serv->sv_nrpools];
356}
357
358int svc_rpcb_setup(struct svc_serv *serv, struct net *net)
359{
360 int err;
361
362 err = rpcb_create_local(net);
363 if (err)
364 return err;
365
366 /* Remove any stale portmap registrations */
367 svc_unregister(serv, net);
368 return 0;
369}
370EXPORT_SYMBOL_GPL(svc_rpcb_setup);
371
372void svc_rpcb_cleanup(struct svc_serv *serv, struct net *net)
373{
374 svc_unregister(serv, net);
375 rpcb_put_local(net);
376}
377EXPORT_SYMBOL_GPL(svc_rpcb_cleanup);
378
379static int svc_uses_rpcbind(struct svc_serv *serv)
380{
381 struct svc_program *progp;
382 unsigned int i;
383
384 for (progp = serv->sv_program; progp; progp = progp->pg_next) {
385 for (i = 0; i < progp->pg_nvers; i++) {
386 if (progp->pg_vers[i] == NULL)
387 continue;
388 if (progp->pg_vers[i]->vs_hidden == 0)
389 return 1;
390 }
391 }
392
393 return 0;
394}
395
396int svc_bind(struct svc_serv *serv, struct net *net)
397{
398 if (!svc_uses_rpcbind(serv))
399 return 0;
400 return svc_rpcb_setup(serv, net);
401}
402EXPORT_SYMBOL_GPL(svc_bind);
403
404#if defined(CONFIG_SUNRPC_BACKCHANNEL)
405static void
406__svc_init_bc(struct svc_serv *serv)
407{
408 INIT_LIST_HEAD(&serv->sv_cb_list);
409 spin_lock_init(&serv->sv_cb_lock);
410 init_waitqueue_head(&serv->sv_cb_waitq);
411}
412#else
413static void
414__svc_init_bc(struct svc_serv *serv)
415{
416}
417#endif
418
419/*
420 * Create an RPC service
421 */
422static struct svc_serv *
423__svc_create(struct svc_program *prog, unsigned int bufsize, int npools,
424 struct svc_serv_ops *ops)
425{
426 struct svc_serv *serv;
427 unsigned int vers;
428 unsigned int xdrsize;
429 unsigned int i;
430
431 if (!(serv = kzalloc(sizeof(*serv), GFP_KERNEL)))
432 return NULL;
433 serv->sv_name = prog->pg_name;
434 serv->sv_program = prog;
435 serv->sv_nrthreads = 1;
436 serv->sv_stats = prog->pg_stats;
437 if (bufsize > RPCSVC_MAXPAYLOAD)
438 bufsize = RPCSVC_MAXPAYLOAD;
439 serv->sv_max_payload = bufsize? bufsize : 4096;
440 serv->sv_max_mesg = roundup(serv->sv_max_payload + PAGE_SIZE, PAGE_SIZE);
441 serv->sv_ops = ops;
442 xdrsize = 0;
443 while (prog) {
444 prog->pg_lovers = prog->pg_nvers-1;
445 for (vers=0; vers<prog->pg_nvers ; vers++)
446 if (prog->pg_vers[vers]) {
447 prog->pg_hivers = vers;
448 if (prog->pg_lovers > vers)
449 prog->pg_lovers = vers;
450 if (prog->pg_vers[vers]->vs_xdrsize > xdrsize)
451 xdrsize = prog->pg_vers[vers]->vs_xdrsize;
452 }
453 prog = prog->pg_next;
454 }
455 serv->sv_xdrsize = xdrsize;
456 INIT_LIST_HEAD(&serv->sv_tempsocks);
457 INIT_LIST_HEAD(&serv->sv_permsocks);
458 init_timer(&serv->sv_temptimer);
459 spin_lock_init(&serv->sv_lock);
460
461 __svc_init_bc(serv);
462
463 serv->sv_nrpools = npools;
464 serv->sv_pools =
465 kcalloc(serv->sv_nrpools, sizeof(struct svc_pool),
466 GFP_KERNEL);
467 if (!serv->sv_pools) {
468 kfree(serv);
469 return NULL;
470 }
471
472 for (i = 0; i < serv->sv_nrpools; i++) {
473 struct svc_pool *pool = &serv->sv_pools[i];
474
475 dprintk("svc: initialising pool %u for %s\n",
476 i, serv->sv_name);
477
478 pool->sp_id = i;
479 INIT_LIST_HEAD(&pool->sp_sockets);
480 INIT_LIST_HEAD(&pool->sp_all_threads);
481 spin_lock_init(&pool->sp_lock);
482 }
483
484 return serv;
485}
486
487struct svc_serv *
488svc_create(struct svc_program *prog, unsigned int bufsize,
489 struct svc_serv_ops *ops)
490{
491 return __svc_create(prog, bufsize, /*npools*/1, ops);
492}
493EXPORT_SYMBOL_GPL(svc_create);
494
495struct svc_serv *
496svc_create_pooled(struct svc_program *prog, unsigned int bufsize,
497 struct svc_serv_ops *ops)
498{
499 struct svc_serv *serv;
500 unsigned int npools = svc_pool_map_get();
501
502 serv = __svc_create(prog, bufsize, npools, ops);
503 if (!serv)
504 goto out_err;
505 return serv;
506out_err:
507 svc_pool_map_put();
508 return NULL;
509}
510EXPORT_SYMBOL_GPL(svc_create_pooled);
511
512void svc_shutdown_net(struct svc_serv *serv, struct net *net)
513{
514 svc_close_net(serv, net);
515
516 if (serv->sv_ops->svo_shutdown)
517 serv->sv_ops->svo_shutdown(serv, net);
518}
519EXPORT_SYMBOL_GPL(svc_shutdown_net);
520
521/*
522 * Destroy an RPC service. Should be called with appropriate locking to
523 * protect the sv_nrthreads, sv_permsocks and sv_tempsocks.
524 */
525void
526svc_destroy(struct svc_serv *serv)
527{
528 dprintk("svc: svc_destroy(%s, %d)\n",
529 serv->sv_program->pg_name,
530 serv->sv_nrthreads);
531
532 if (serv->sv_nrthreads) {
533 if (--(serv->sv_nrthreads) != 0) {
534 svc_sock_update_bufs(serv);
535 return;
536 }
537 } else
538 printk("svc_destroy: no threads for serv=%p!\n", serv);
539
540 del_timer_sync(&serv->sv_temptimer);
541
542 /*
543 * The last user is gone and thus all sockets have to be destroyed to
544 * the point. Check this.
545 */
546 BUG_ON(!list_empty(&serv->sv_permsocks));
547 BUG_ON(!list_empty(&serv->sv_tempsocks));
548
549 cache_clean_deferred(serv);
550
551 if (svc_serv_is_pooled(serv))
552 svc_pool_map_put();
553
554 kfree(serv->sv_pools);
555 kfree(serv);
556}
557EXPORT_SYMBOL_GPL(svc_destroy);
558
559/*
560 * Allocate an RPC server's buffer space.
561 * We allocate pages and place them in rq_argpages.
562 */
563static int
564svc_init_buffer(struct svc_rqst *rqstp, unsigned int size, int node)
565{
566 unsigned int pages, arghi;
567
568 /* bc_xprt uses fore channel allocated buffers */
569 if (svc_is_backchannel(rqstp))
570 return 1;
571
572 pages = size / PAGE_SIZE + 1; /* extra page as we hold both request and reply.
573 * We assume one is at most one page
574 */
575 arghi = 0;
576 WARN_ON_ONCE(pages > RPCSVC_MAXPAGES);
577 if (pages > RPCSVC_MAXPAGES)
578 pages = RPCSVC_MAXPAGES;
579 while (pages) {
580 struct page *p = alloc_pages_node(node, GFP_KERNEL, 0);
581 if (!p)
582 break;
583 rqstp->rq_pages[arghi++] = p;
584 pages--;
585 }
586 return pages == 0;
587}
588
589/*
590 * Release an RPC server buffer
591 */
592static void
593svc_release_buffer(struct svc_rqst *rqstp)
594{
595 unsigned int i;
596
597 for (i = 0; i < ARRAY_SIZE(rqstp->rq_pages); i++)
598 if (rqstp->rq_pages[i])
599 put_page(rqstp->rq_pages[i]);
600}
601
602struct svc_rqst *
603svc_rqst_alloc(struct svc_serv *serv, struct svc_pool *pool, int node)
604{
605 struct svc_rqst *rqstp;
606
607 rqstp = kzalloc_node(sizeof(*rqstp), GFP_KERNEL, node);
608 if (!rqstp)
609 return rqstp;
610
611 __set_bit(RQ_BUSY, &rqstp->rq_flags);
612 spin_lock_init(&rqstp->rq_lock);
613 rqstp->rq_server = serv;
614 rqstp->rq_pool = pool;
615
616 rqstp->rq_argp = kmalloc_node(serv->sv_xdrsize, GFP_KERNEL, node);
617 if (!rqstp->rq_argp)
618 goto out_enomem;
619
620 rqstp->rq_resp = kmalloc_node(serv->sv_xdrsize, GFP_KERNEL, node);
621 if (!rqstp->rq_resp)
622 goto out_enomem;
623
624 if (!svc_init_buffer(rqstp, serv->sv_max_mesg, node))
625 goto out_enomem;
626
627 return rqstp;
628out_enomem:
629 svc_rqst_free(rqstp);
630 return NULL;
631}
632EXPORT_SYMBOL_GPL(svc_rqst_alloc);
633
634struct svc_rqst *
635svc_prepare_thread(struct svc_serv *serv, struct svc_pool *pool, int node)
636{
637 struct svc_rqst *rqstp;
638
639 rqstp = svc_rqst_alloc(serv, pool, node);
640 if (!rqstp)
641 return ERR_PTR(-ENOMEM);
642
643 serv->sv_nrthreads++;
644 spin_lock_bh(&pool->sp_lock);
645 pool->sp_nrthreads++;
646 list_add_rcu(&rqstp->rq_all, &pool->sp_all_threads);
647 spin_unlock_bh(&pool->sp_lock);
648 return rqstp;
649}
650EXPORT_SYMBOL_GPL(svc_prepare_thread);
651
652/*
653 * Choose a pool in which to create a new thread, for svc_set_num_threads
654 */
655static inline struct svc_pool *
656choose_pool(struct svc_serv *serv, struct svc_pool *pool, unsigned int *state)
657{
658 if (pool != NULL)
659 return pool;
660
661 return &serv->sv_pools[(*state)++ % serv->sv_nrpools];
662}
663
664/*
665 * Choose a thread to kill, for svc_set_num_threads
666 */
667static inline struct task_struct *
668choose_victim(struct svc_serv *serv, struct svc_pool *pool, unsigned int *state)
669{
670 unsigned int i;
671 struct task_struct *task = NULL;
672
673 if (pool != NULL) {
674 spin_lock_bh(&pool->sp_lock);
675 } else {
676 /* choose a pool in round-robin fashion */
677 for (i = 0; i < serv->sv_nrpools; i++) {
678 pool = &serv->sv_pools[--(*state) % serv->sv_nrpools];
679 spin_lock_bh(&pool->sp_lock);
680 if (!list_empty(&pool->sp_all_threads))
681 goto found_pool;
682 spin_unlock_bh(&pool->sp_lock);
683 }
684 return NULL;
685 }
686
687found_pool:
688 if (!list_empty(&pool->sp_all_threads)) {
689 struct svc_rqst *rqstp;
690
691 /*
692 * Remove from the pool->sp_all_threads list
693 * so we don't try to kill it again.
694 */
695 rqstp = list_entry(pool->sp_all_threads.next, struct svc_rqst, rq_all);
696 set_bit(RQ_VICTIM, &rqstp->rq_flags);
697 list_del_rcu(&rqstp->rq_all);
698 task = rqstp->rq_task;
699 }
700 spin_unlock_bh(&pool->sp_lock);
701
702 return task;
703}
704
705/*
706 * Create or destroy enough new threads to make the number
707 * of threads the given number. If `pool' is non-NULL, applies
708 * only to threads in that pool, otherwise round-robins between
709 * all pools. Caller must ensure that mutual exclusion between this and
710 * server startup or shutdown.
711 *
712 * Destroying threads relies on the service threads filling in
713 * rqstp->rq_task, which only the nfs ones do. Assumes the serv
714 * has been created using svc_create_pooled().
715 *
716 * Based on code that used to be in nfsd_svc() but tweaked
717 * to be pool-aware.
718 */
719int
720svc_set_num_threads(struct svc_serv *serv, struct svc_pool *pool, int nrservs)
721{
722 struct svc_rqst *rqstp;
723 struct task_struct *task;
724 struct svc_pool *chosen_pool;
725 int error = 0;
726 unsigned int state = serv->sv_nrthreads-1;
727 int node;
728
729 if (pool == NULL) {
730 /* The -1 assumes caller has done a svc_get() */
731 nrservs -= (serv->sv_nrthreads-1);
732 } else {
733 spin_lock_bh(&pool->sp_lock);
734 nrservs -= pool->sp_nrthreads;
735 spin_unlock_bh(&pool->sp_lock);
736 }
737
738 /* create new threads */
739 while (nrservs > 0) {
740 nrservs--;
741 chosen_pool = choose_pool(serv, pool, &state);
742
743 node = svc_pool_map_get_node(chosen_pool->sp_id);
744 rqstp = svc_prepare_thread(serv, chosen_pool, node);
745 if (IS_ERR(rqstp)) {
746 error = PTR_ERR(rqstp);
747 break;
748 }
749
750 __module_get(serv->sv_ops->svo_module);
751 task = kthread_create_on_node(serv->sv_ops->svo_function, rqstp,
752 node, "%s", serv->sv_name);
753 if (IS_ERR(task)) {
754 error = PTR_ERR(task);
755 module_put(serv->sv_ops->svo_module);
756 svc_exit_thread(rqstp);
757 break;
758 }
759
760 rqstp->rq_task = task;
761 if (serv->sv_nrpools > 1)
762 svc_pool_map_set_cpumask(task, chosen_pool->sp_id);
763
764 svc_sock_update_bufs(serv);
765 wake_up_process(task);
766 }
767 /* destroy old threads */
768 while (nrservs < 0 &&
769 (task = choose_victim(serv, pool, &state)) != NULL) {
770 send_sig(SIGINT, task, 1);
771 nrservs++;
772 }
773
774 return error;
775}
776EXPORT_SYMBOL_GPL(svc_set_num_threads);
777
778/*
779 * Called from a server thread as it's exiting. Caller must hold the "service
780 * mutex" for the service.
781 */
782void
783svc_rqst_free(struct svc_rqst *rqstp)
784{
785 svc_release_buffer(rqstp);
786 kfree(rqstp->rq_resp);
787 kfree(rqstp->rq_argp);
788 kfree(rqstp->rq_auth_data);
789 kfree_rcu(rqstp, rq_rcu_head);
790}
791EXPORT_SYMBOL_GPL(svc_rqst_free);
792
793void
794svc_exit_thread(struct svc_rqst *rqstp)
795{
796 struct svc_serv *serv = rqstp->rq_server;
797 struct svc_pool *pool = rqstp->rq_pool;
798
799 spin_lock_bh(&pool->sp_lock);
800 pool->sp_nrthreads--;
801 if (!test_and_set_bit(RQ_VICTIM, &rqstp->rq_flags))
802 list_del_rcu(&rqstp->rq_all);
803 spin_unlock_bh(&pool->sp_lock);
804
805 svc_rqst_free(rqstp);
806
807 /* Release the server */
808 if (serv)
809 svc_destroy(serv);
810}
811EXPORT_SYMBOL_GPL(svc_exit_thread);
812
813/*
814 * Register an "inet" protocol family netid with the local
815 * rpcbind daemon via an rpcbind v4 SET request.
816 *
817 * No netconfig infrastructure is available in the kernel, so
818 * we map IP_ protocol numbers to netids by hand.
819 *
820 * Returns zero on success; a negative errno value is returned
821 * if any error occurs.
822 */
823static int __svc_rpcb_register4(struct net *net, const u32 program,
824 const u32 version,
825 const unsigned short protocol,
826 const unsigned short port)
827{
828 const struct sockaddr_in sin = {
829 .sin_family = AF_INET,
830 .sin_addr.s_addr = htonl(INADDR_ANY),
831 .sin_port = htons(port),
832 };
833 const char *netid;
834 int error;
835
836 switch (protocol) {
837 case IPPROTO_UDP:
838 netid = RPCBIND_NETID_UDP;
839 break;
840 case IPPROTO_TCP:
841 netid = RPCBIND_NETID_TCP;
842 break;
843 default:
844 return -ENOPROTOOPT;
845 }
846
847 error = rpcb_v4_register(net, program, version,
848 (const struct sockaddr *)&sin, netid);
849
850 /*
851 * User space didn't support rpcbind v4, so retry this
852 * registration request with the legacy rpcbind v2 protocol.
853 */
854 if (error == -EPROTONOSUPPORT)
855 error = rpcb_register(net, program, version, protocol, port);
856
857 return error;
858}
859
860#if IS_ENABLED(CONFIG_IPV6)
861/*
862 * Register an "inet6" protocol family netid with the local
863 * rpcbind daemon via an rpcbind v4 SET request.
864 *
865 * No netconfig infrastructure is available in the kernel, so
866 * we map IP_ protocol numbers to netids by hand.
867 *
868 * Returns zero on success; a negative errno value is returned
869 * if any error occurs.
870 */
871static int __svc_rpcb_register6(struct net *net, const u32 program,
872 const u32 version,
873 const unsigned short protocol,
874 const unsigned short port)
875{
876 const struct sockaddr_in6 sin6 = {
877 .sin6_family = AF_INET6,
878 .sin6_addr = IN6ADDR_ANY_INIT,
879 .sin6_port = htons(port),
880 };
881 const char *netid;
882 int error;
883
884 switch (protocol) {
885 case IPPROTO_UDP:
886 netid = RPCBIND_NETID_UDP6;
887 break;
888 case IPPROTO_TCP:
889 netid = RPCBIND_NETID_TCP6;
890 break;
891 default:
892 return -ENOPROTOOPT;
893 }
894
895 error = rpcb_v4_register(net, program, version,
896 (const struct sockaddr *)&sin6, netid);
897
898 /*
899 * User space didn't support rpcbind version 4, so we won't
900 * use a PF_INET6 listener.
901 */
902 if (error == -EPROTONOSUPPORT)
903 error = -EAFNOSUPPORT;
904
905 return error;
906}
907#endif /* IS_ENABLED(CONFIG_IPV6) */
908
909/*
910 * Register a kernel RPC service via rpcbind version 4.
911 *
912 * Returns zero on success; a negative errno value is returned
913 * if any error occurs.
914 */
915static int __svc_register(struct net *net, const char *progname,
916 const u32 program, const u32 version,
917 const int family,
918 const unsigned short protocol,
919 const unsigned short port)
920{
921 int error = -EAFNOSUPPORT;
922
923 switch (family) {
924 case PF_INET:
925 error = __svc_rpcb_register4(net, program, version,
926 protocol, port);
927 break;
928#if IS_ENABLED(CONFIG_IPV6)
929 case PF_INET6:
930 error = __svc_rpcb_register6(net, program, version,
931 protocol, port);
932#endif
933 }
934
935 return error;
936}
937
938/**
939 * svc_register - register an RPC service with the local portmapper
940 * @serv: svc_serv struct for the service to register
941 * @net: net namespace for the service to register
942 * @family: protocol family of service's listener socket
943 * @proto: transport protocol number to advertise
944 * @port: port to advertise
945 *
946 * Service is registered for any address in the passed-in protocol family
947 */
948int svc_register(const struct svc_serv *serv, struct net *net,
949 const int family, const unsigned short proto,
950 const unsigned short port)
951{
952 struct svc_program *progp;
953 struct svc_version *vers;
954 unsigned int i;
955 int error = 0;
956
957 WARN_ON_ONCE(proto == 0 && port == 0);
958 if (proto == 0 && port == 0)
959 return -EINVAL;
960
961 for (progp = serv->sv_program; progp; progp = progp->pg_next) {
962 for (i = 0; i < progp->pg_nvers; i++) {
963 vers = progp->pg_vers[i];
964 if (vers == NULL)
965 continue;
966
967 dprintk("svc: svc_register(%sv%d, %s, %u, %u)%s\n",
968 progp->pg_name,
969 i,
970 proto == IPPROTO_UDP? "udp" : "tcp",
971 port,
972 family,
973 vers->vs_hidden ?
974 " (but not telling portmap)" : "");
975
976 if (vers->vs_hidden)
977 continue;
978
979 error = __svc_register(net, progp->pg_name, progp->pg_prog,
980 i, family, proto, port);
981
982 if (vers->vs_rpcb_optnl) {
983 error = 0;
984 continue;
985 }
986
987 if (error < 0) {
988 printk(KERN_WARNING "svc: failed to register "
989 "%sv%u RPC service (errno %d).\n",
990 progp->pg_name, i, -error);
991 break;
992 }
993 }
994 }
995
996 return error;
997}
998
999/*
1000 * If user space is running rpcbind, it should take the v4 UNSET
1001 * and clear everything for this [program, version]. If user space
1002 * is running portmap, it will reject the v4 UNSET, but won't have
1003 * any "inet6" entries anyway. So a PMAP_UNSET should be sufficient
1004 * in this case to clear all existing entries for [program, version].
1005 */
1006static void __svc_unregister(struct net *net, const u32 program, const u32 version,
1007 const char *progname)
1008{
1009 int error;
1010
1011 error = rpcb_v4_register(net, program, version, NULL, "");
1012
1013 /*
1014 * User space didn't support rpcbind v4, so retry this
1015 * request with the legacy rpcbind v2 protocol.
1016 */
1017 if (error == -EPROTONOSUPPORT)
1018 error = rpcb_register(net, program, version, 0, 0);
1019
1020 dprintk("svc: %s(%sv%u), error %d\n",
1021 __func__, progname, version, error);
1022}
1023
1024/*
1025 * All netids, bind addresses and ports registered for [program, version]
1026 * are removed from the local rpcbind database (if the service is not
1027 * hidden) to make way for a new instance of the service.
1028 *
1029 * The result of unregistration is reported via dprintk for those who want
1030 * verification of the result, but is otherwise not important.
1031 */
1032static void svc_unregister(const struct svc_serv *serv, struct net *net)
1033{
1034 struct svc_program *progp;
1035 unsigned long flags;
1036 unsigned int i;
1037
1038 clear_thread_flag(TIF_SIGPENDING);
1039
1040 for (progp = serv->sv_program; progp; progp = progp->pg_next) {
1041 for (i = 0; i < progp->pg_nvers; i++) {
1042 if (progp->pg_vers[i] == NULL)
1043 continue;
1044 if (progp->pg_vers[i]->vs_hidden)
1045 continue;
1046
1047 dprintk("svc: attempting to unregister %sv%u\n",
1048 progp->pg_name, i);
1049 __svc_unregister(net, progp->pg_prog, i, progp->pg_name);
1050 }
1051 }
1052
1053 spin_lock_irqsave(¤t->sighand->siglock, flags);
1054 recalc_sigpending();
1055 spin_unlock_irqrestore(¤t->sighand->siglock, flags);
1056}
1057
1058/*
1059 * dprintk the given error with the address of the client that caused it.
1060 */
1061#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
1062static __printf(2, 3)
1063void svc_printk(struct svc_rqst *rqstp, const char *fmt, ...)
1064{
1065 struct va_format vaf;
1066 va_list args;
1067 char buf[RPC_MAX_ADDRBUFLEN];
1068
1069 va_start(args, fmt);
1070
1071 vaf.fmt = fmt;
1072 vaf.va = &args;
1073
1074 dprintk("svc: %s: %pV", svc_print_addr(rqstp, buf, sizeof(buf)), &vaf);
1075
1076 va_end(args);
1077}
1078#else
1079static __printf(2,3) void svc_printk(struct svc_rqst *rqstp, const char *fmt, ...) {}
1080#endif
1081
1082/*
1083 * Common routine for processing the RPC request.
1084 */
1085static int
1086svc_process_common(struct svc_rqst *rqstp, struct kvec *argv, struct kvec *resv)
1087{
1088 struct svc_program *progp;
1089 struct svc_version *versp = NULL; /* compiler food */
1090 struct svc_procedure *procp = NULL;
1091 struct svc_serv *serv = rqstp->rq_server;
1092 kxdrproc_t xdr;
1093 __be32 *statp;
1094 u32 prog, vers, proc;
1095 __be32 auth_stat, rpc_stat;
1096 int auth_res;
1097 __be32 *reply_statp;
1098
1099 rpc_stat = rpc_success;
1100
1101 if (argv->iov_len < 6*4)
1102 goto err_short_len;
1103
1104 /* Will be turned off only in gss privacy case: */
1105 set_bit(RQ_SPLICE_OK, &rqstp->rq_flags);
1106 /* Will be turned off only when NFSv4 Sessions are used */
1107 set_bit(RQ_USEDEFERRAL, &rqstp->rq_flags);
1108 clear_bit(RQ_DROPME, &rqstp->rq_flags);
1109
1110 /* Setup reply header */
1111 rqstp->rq_xprt->xpt_ops->xpo_prep_reply_hdr(rqstp);
1112
1113 svc_putu32(resv, rqstp->rq_xid);
1114
1115 vers = svc_getnl(argv);
1116
1117 /* First words of reply: */
1118 svc_putnl(resv, 1); /* REPLY */
1119
1120 if (vers != 2) /* RPC version number */
1121 goto err_bad_rpc;
1122
1123 /* Save position in case we later decide to reject: */
1124 reply_statp = resv->iov_base + resv->iov_len;
1125
1126 svc_putnl(resv, 0); /* ACCEPT */
1127
1128 rqstp->rq_prog = prog = svc_getnl(argv); /* program number */
1129 rqstp->rq_vers = vers = svc_getnl(argv); /* version number */
1130 rqstp->rq_proc = proc = svc_getnl(argv); /* procedure number */
1131
1132 for (progp = serv->sv_program; progp; progp = progp->pg_next)
1133 if (prog == progp->pg_prog)
1134 break;
1135
1136 /*
1137 * Decode auth data, and add verifier to reply buffer.
1138 * We do this before anything else in order to get a decent
1139 * auth verifier.
1140 */
1141 auth_res = svc_authenticate(rqstp, &auth_stat);
1142 /* Also give the program a chance to reject this call: */
1143 if (auth_res == SVC_OK && progp) {
1144 auth_stat = rpc_autherr_badcred;
1145 auth_res = progp->pg_authenticate(rqstp);
1146 }
1147 switch (auth_res) {
1148 case SVC_OK:
1149 break;
1150 case SVC_GARBAGE:
1151 goto err_garbage;
1152 case SVC_SYSERR:
1153 rpc_stat = rpc_system_err;
1154 goto err_bad;
1155 case SVC_DENIED:
1156 goto err_bad_auth;
1157 case SVC_CLOSE:
1158 goto close;
1159 case SVC_DROP:
1160 goto dropit;
1161 case SVC_COMPLETE:
1162 goto sendit;
1163 }
1164
1165 if (progp == NULL)
1166 goto err_bad_prog;
1167
1168 if (vers >= progp->pg_nvers ||
1169 !(versp = progp->pg_vers[vers]))
1170 goto err_bad_vers;
1171
1172 procp = versp->vs_proc + proc;
1173 if (proc >= versp->vs_nproc || !procp->pc_func)
1174 goto err_bad_proc;
1175 rqstp->rq_procinfo = procp;
1176
1177 /* Syntactic check complete */
1178 serv->sv_stats->rpccnt++;
1179
1180 /* Build the reply header. */
1181 statp = resv->iov_base +resv->iov_len;
1182 svc_putnl(resv, RPC_SUCCESS);
1183
1184 /* Bump per-procedure stats counter */
1185 procp->pc_count++;
1186
1187 /* Initialize storage for argp and resp */
1188 memset(rqstp->rq_argp, 0, procp->pc_argsize);
1189 memset(rqstp->rq_resp, 0, procp->pc_ressize);
1190
1191 /* un-reserve some of the out-queue now that we have a
1192 * better idea of reply size
1193 */
1194 if (procp->pc_xdrressize)
1195 svc_reserve_auth(rqstp, procp->pc_xdrressize<<2);
1196
1197 /* Call the function that processes the request. */
1198 if (!versp->vs_dispatch) {
1199 /* Decode arguments */
1200 xdr = procp->pc_decode;
1201 if (xdr && !xdr(rqstp, argv->iov_base, rqstp->rq_argp))
1202 goto err_garbage;
1203
1204 *statp = procp->pc_func(rqstp, rqstp->rq_argp, rqstp->rq_resp);
1205
1206 /* Encode reply */
1207 if (*statp == rpc_drop_reply ||
1208 test_bit(RQ_DROPME, &rqstp->rq_flags)) {
1209 if (procp->pc_release)
1210 procp->pc_release(rqstp, NULL, rqstp->rq_resp);
1211 goto dropit;
1212 }
1213 if (*statp == rpc_autherr_badcred) {
1214 if (procp->pc_release)
1215 procp->pc_release(rqstp, NULL, rqstp->rq_resp);
1216 goto err_bad_auth;
1217 }
1218 if (*statp == rpc_success &&
1219 (xdr = procp->pc_encode) &&
1220 !xdr(rqstp, resv->iov_base+resv->iov_len, rqstp->rq_resp)) {
1221 dprintk("svc: failed to encode reply\n");
1222 /* serv->sv_stats->rpcsystemerr++; */
1223 *statp = rpc_system_err;
1224 }
1225 } else {
1226 dprintk("svc: calling dispatcher\n");
1227 if (!versp->vs_dispatch(rqstp, statp)) {
1228 /* Release reply info */
1229 if (procp->pc_release)
1230 procp->pc_release(rqstp, NULL, rqstp->rq_resp);
1231 goto dropit;
1232 }
1233 }
1234
1235 /* Check RPC status result */
1236 if (*statp != rpc_success)
1237 resv->iov_len = ((void*)statp) - resv->iov_base + 4;
1238
1239 /* Release reply info */
1240 if (procp->pc_release)
1241 procp->pc_release(rqstp, NULL, rqstp->rq_resp);
1242
1243 if (procp->pc_encode == NULL)
1244 goto dropit;
1245
1246 sendit:
1247 if (svc_authorise(rqstp))
1248 goto close;
1249 return 1; /* Caller can now send it */
1250
1251 dropit:
1252 svc_authorise(rqstp); /* doesn't hurt to call this twice */
1253 dprintk("svc: svc_process dropit\n");
1254 return 0;
1255
1256 close:
1257 if (test_bit(XPT_TEMP, &rqstp->rq_xprt->xpt_flags))
1258 svc_close_xprt(rqstp->rq_xprt);
1259 dprintk("svc: svc_process close\n");
1260 return 0;
1261
1262err_short_len:
1263 svc_printk(rqstp, "short len %Zd, dropping request\n",
1264 argv->iov_len);
1265 goto close;
1266
1267err_bad_rpc:
1268 serv->sv_stats->rpcbadfmt++;
1269 svc_putnl(resv, 1); /* REJECT */
1270 svc_putnl(resv, 0); /* RPC_MISMATCH */
1271 svc_putnl(resv, 2); /* Only RPCv2 supported */
1272 svc_putnl(resv, 2);
1273 goto sendit;
1274
1275err_bad_auth:
1276 dprintk("svc: authentication failed (%d)\n", ntohl(auth_stat));
1277 serv->sv_stats->rpcbadauth++;
1278 /* Restore write pointer to location of accept status: */
1279 xdr_ressize_check(rqstp, reply_statp);
1280 svc_putnl(resv, 1); /* REJECT */
1281 svc_putnl(resv, 1); /* AUTH_ERROR */
1282 svc_putnl(resv, ntohl(auth_stat)); /* status */
1283 goto sendit;
1284
1285err_bad_prog:
1286 dprintk("svc: unknown program %d\n", prog);
1287 serv->sv_stats->rpcbadfmt++;
1288 svc_putnl(resv, RPC_PROG_UNAVAIL);
1289 goto sendit;
1290
1291err_bad_vers:
1292 svc_printk(rqstp, "unknown version (%d for prog %d, %s)\n",
1293 vers, prog, progp->pg_name);
1294
1295 serv->sv_stats->rpcbadfmt++;
1296 svc_putnl(resv, RPC_PROG_MISMATCH);
1297 svc_putnl(resv, progp->pg_lovers);
1298 svc_putnl(resv, progp->pg_hivers);
1299 goto sendit;
1300
1301err_bad_proc:
1302 svc_printk(rqstp, "unknown procedure (%d)\n", proc);
1303
1304 serv->sv_stats->rpcbadfmt++;
1305 svc_putnl(resv, RPC_PROC_UNAVAIL);
1306 goto sendit;
1307
1308err_garbage:
1309 svc_printk(rqstp, "failed to decode args\n");
1310
1311 rpc_stat = rpc_garbage_args;
1312err_bad:
1313 serv->sv_stats->rpcbadfmt++;
1314 svc_putnl(resv, ntohl(rpc_stat));
1315 goto sendit;
1316}
1317
1318/*
1319 * Process the RPC request.
1320 */
1321int
1322svc_process(struct svc_rqst *rqstp)
1323{
1324 struct kvec *argv = &rqstp->rq_arg.head[0];
1325 struct kvec *resv = &rqstp->rq_res.head[0];
1326 struct svc_serv *serv = rqstp->rq_server;
1327 u32 dir;
1328
1329 /*
1330 * Setup response xdr_buf.
1331 * Initially it has just one page
1332 */
1333 rqstp->rq_next_page = &rqstp->rq_respages[1];
1334 resv->iov_base = page_address(rqstp->rq_respages[0]);
1335 resv->iov_len = 0;
1336 rqstp->rq_res.pages = rqstp->rq_respages + 1;
1337 rqstp->rq_res.len = 0;
1338 rqstp->rq_res.page_base = 0;
1339 rqstp->rq_res.page_len = 0;
1340 rqstp->rq_res.buflen = PAGE_SIZE;
1341 rqstp->rq_res.tail[0].iov_base = NULL;
1342 rqstp->rq_res.tail[0].iov_len = 0;
1343
1344 dir = svc_getnl(argv);
1345 if (dir != 0) {
1346 /* direction != CALL */
1347 svc_printk(rqstp, "bad direction %d, dropping request\n", dir);
1348 serv->sv_stats->rpcbadfmt++;
1349 goto out_drop;
1350 }
1351
1352 /* Returns 1 for send, 0 for drop */
1353 if (likely(svc_process_common(rqstp, argv, resv))) {
1354 int ret = svc_send(rqstp);
1355
1356 trace_svc_process(rqstp, ret);
1357 return ret;
1358 }
1359out_drop:
1360 trace_svc_process(rqstp, 0);
1361 svc_drop(rqstp);
1362 return 0;
1363}
1364EXPORT_SYMBOL_GPL(svc_process);
1365
1366#if defined(CONFIG_SUNRPC_BACKCHANNEL)
1367/*
1368 * Process a backchannel RPC request that arrived over an existing
1369 * outbound connection
1370 */
1371int
1372bc_svc_process(struct svc_serv *serv, struct rpc_rqst *req,
1373 struct svc_rqst *rqstp)
1374{
1375 struct kvec *argv = &rqstp->rq_arg.head[0];
1376 struct kvec *resv = &rqstp->rq_res.head[0];
1377 struct rpc_task *task;
1378 int proc_error;
1379 int error;
1380
1381 dprintk("svc: %s(%p)\n", __func__, req);
1382
1383 /* Build the svc_rqst used by the common processing routine */
1384 rqstp->rq_xprt = serv->sv_bc_xprt;
1385 rqstp->rq_xid = req->rq_xid;
1386 rqstp->rq_prot = req->rq_xprt->prot;
1387 rqstp->rq_server = serv;
1388
1389 rqstp->rq_addrlen = sizeof(req->rq_xprt->addr);
1390 memcpy(&rqstp->rq_addr, &req->rq_xprt->addr, rqstp->rq_addrlen);
1391 memcpy(&rqstp->rq_arg, &req->rq_rcv_buf, sizeof(rqstp->rq_arg));
1392 memcpy(&rqstp->rq_res, &req->rq_snd_buf, sizeof(rqstp->rq_res));
1393
1394 /* Adjust the argument buffer length */
1395 rqstp->rq_arg.len = req->rq_private_buf.len;
1396 if (rqstp->rq_arg.len <= rqstp->rq_arg.head[0].iov_len) {
1397 rqstp->rq_arg.head[0].iov_len = rqstp->rq_arg.len;
1398 rqstp->rq_arg.page_len = 0;
1399 } else if (rqstp->rq_arg.len <= rqstp->rq_arg.head[0].iov_len +
1400 rqstp->rq_arg.page_len)
1401 rqstp->rq_arg.page_len = rqstp->rq_arg.len -
1402 rqstp->rq_arg.head[0].iov_len;
1403 else
1404 rqstp->rq_arg.len = rqstp->rq_arg.head[0].iov_len +
1405 rqstp->rq_arg.page_len;
1406
1407 /* reset result send buffer "put" position */
1408 resv->iov_len = 0;
1409
1410 /*
1411 * Skip the next two words because they've already been
1412 * processed in the transport
1413 */
1414 svc_getu32(argv); /* XID */
1415 svc_getnl(argv); /* CALLDIR */
1416
1417 /* Parse and execute the bc call */
1418 proc_error = svc_process_common(rqstp, argv, resv);
1419
1420 atomic_inc(&req->rq_xprt->bc_free_slots);
1421 if (!proc_error) {
1422 /* Processing error: drop the request */
1423 xprt_free_bc_request(req);
1424 return 0;
1425 }
1426
1427 /* Finally, send the reply synchronously */
1428 memcpy(&req->rq_snd_buf, &rqstp->rq_res, sizeof(req->rq_snd_buf));
1429 task = rpc_run_bc_task(req);
1430 if (IS_ERR(task)) {
1431 error = PTR_ERR(task);
1432 goto out;
1433 }
1434
1435 WARN_ON_ONCE(atomic_read(&task->tk_count) != 1);
1436 error = task->tk_status;
1437 rpc_put_task(task);
1438
1439out:
1440 dprintk("svc: %s(), error=%d\n", __func__, error);
1441 return error;
1442}
1443EXPORT_SYMBOL_GPL(bc_svc_process);
1444#endif /* CONFIG_SUNRPC_BACKCHANNEL */
1445
1446/*
1447 * Return (transport-specific) limit on the rpc payload.
1448 */
1449u32 svc_max_payload(const struct svc_rqst *rqstp)
1450{
1451 u32 max = rqstp->rq_xprt->xpt_class->xcl_max_payload;
1452
1453 if (rqstp->rq_server->sv_max_payload < max)
1454 max = rqstp->rq_server->sv_max_payload;
1455 return max;
1456}
1457EXPORT_SYMBOL_GPL(svc_max_payload);