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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * linux/net/sunrpc/svc.c
4 *
5 * High-level RPC service routines
6 *
7 * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
8 *
9 * Multiple threads pools and NUMAisation
10 * Copyright (c) 2006 Silicon Graphics, Inc.
11 * by Greg Banks <gnb@melbourne.sgi.com>
12 */
13
14#include <linux/linkage.h>
15#include <linux/sched/signal.h>
16#include <linux/errno.h>
17#include <linux/net.h>
18#include <linux/in.h>
19#include <linux/mm.h>
20#include <linux/interrupt.h>
21#include <linux/module.h>
22#include <linux/kthread.h>
23#include <linux/slab.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#include <trace/events/sunrpc.h>
33
34#define RPCDBG_FACILITY RPCDBG_SVCDSP
35
36static void svc_unregister(const struct svc_serv *serv, struct net *net);
37
38#define svc_serv_is_pooled(serv) ((serv)->sv_ops->svo_function)
39
40#define SVC_POOL_DEFAULT SVC_POOL_GLOBAL
41
42/*
43 * Structure for mapping cpus to pools and vice versa.
44 * Setup once during sunrpc initialisation.
45 */
46struct svc_pool_map svc_pool_map = {
47 .mode = SVC_POOL_DEFAULT
48};
49EXPORT_SYMBOL_GPL(svc_pool_map);
50
51static DEFINE_MUTEX(svc_pool_map_mutex);/* protects svc_pool_map.count only */
52
53static int
54param_set_pool_mode(const char *val, const struct kernel_param *kp)
55{
56 int *ip = (int *)kp->arg;
57 struct svc_pool_map *m = &svc_pool_map;
58 int err;
59
60 mutex_lock(&svc_pool_map_mutex);
61
62 err = -EBUSY;
63 if (m->count)
64 goto out;
65
66 err = 0;
67 if (!strncmp(val, "auto", 4))
68 *ip = SVC_POOL_AUTO;
69 else if (!strncmp(val, "global", 6))
70 *ip = SVC_POOL_GLOBAL;
71 else if (!strncmp(val, "percpu", 6))
72 *ip = SVC_POOL_PERCPU;
73 else if (!strncmp(val, "pernode", 7))
74 *ip = SVC_POOL_PERNODE;
75 else
76 err = -EINVAL;
77
78out:
79 mutex_unlock(&svc_pool_map_mutex);
80 return err;
81}
82
83static int
84param_get_pool_mode(char *buf, const struct kernel_param *kp)
85{
86 int *ip = (int *)kp->arg;
87
88 switch (*ip)
89 {
90 case SVC_POOL_AUTO:
91 return strlcpy(buf, "auto", 20);
92 case SVC_POOL_GLOBAL:
93 return strlcpy(buf, "global", 20);
94 case SVC_POOL_PERCPU:
95 return strlcpy(buf, "percpu", 20);
96 case SVC_POOL_PERNODE:
97 return strlcpy(buf, "pernode", 20);
98 default:
99 return sprintf(buf, "%d", *ip);
100 }
101}
102
103module_param_call(pool_mode, param_set_pool_mode, param_get_pool_mode,
104 &svc_pool_map.mode, 0644);
105
106/*
107 * Detect best pool mapping mode heuristically,
108 * according to the machine's topology.
109 */
110static int
111svc_pool_map_choose_mode(void)
112{
113 unsigned int node;
114
115 if (nr_online_nodes > 1) {
116 /*
117 * Actually have multiple NUMA nodes,
118 * so split pools on NUMA node boundaries
119 */
120 return SVC_POOL_PERNODE;
121 }
122
123 node = first_online_node;
124 if (nr_cpus_node(node) > 2) {
125 /*
126 * Non-trivial SMP, or CONFIG_NUMA on
127 * non-NUMA hardware, e.g. with a generic
128 * x86_64 kernel on Xeons. In this case we
129 * want to divide the pools on cpu boundaries.
130 */
131 return SVC_POOL_PERCPU;
132 }
133
134 /* default: one global pool */
135 return SVC_POOL_GLOBAL;
136}
137
138/*
139 * Allocate the to_pool[] and pool_to[] arrays.
140 * Returns 0 on success or an errno.
141 */
142static int
143svc_pool_map_alloc_arrays(struct svc_pool_map *m, unsigned int maxpools)
144{
145 m->to_pool = kcalloc(maxpools, sizeof(unsigned int), GFP_KERNEL);
146 if (!m->to_pool)
147 goto fail;
148 m->pool_to = kcalloc(maxpools, sizeof(unsigned int), GFP_KERNEL);
149 if (!m->pool_to)
150 goto fail_free;
151
152 return 0;
153
154fail_free:
155 kfree(m->to_pool);
156 m->to_pool = NULL;
157fail:
158 return -ENOMEM;
159}
160
161/*
162 * Initialise the pool map for SVC_POOL_PERCPU mode.
163 * Returns number of pools or <0 on error.
164 */
165static int
166svc_pool_map_init_percpu(struct svc_pool_map *m)
167{
168 unsigned int maxpools = nr_cpu_ids;
169 unsigned int pidx = 0;
170 unsigned int cpu;
171 int err;
172
173 err = svc_pool_map_alloc_arrays(m, maxpools);
174 if (err)
175 return err;
176
177 for_each_online_cpu(cpu) {
178 BUG_ON(pidx >= maxpools);
179 m->to_pool[cpu] = pidx;
180 m->pool_to[pidx] = cpu;
181 pidx++;
182 }
183 /* cpus brought online later all get mapped to pool0, sorry */
184
185 return pidx;
186};
187
188
189/*
190 * Initialise the pool map for SVC_POOL_PERNODE mode.
191 * Returns number of pools or <0 on error.
192 */
193static int
194svc_pool_map_init_pernode(struct svc_pool_map *m)
195{
196 unsigned int maxpools = nr_node_ids;
197 unsigned int pidx = 0;
198 unsigned int node;
199 int err;
200
201 err = svc_pool_map_alloc_arrays(m, maxpools);
202 if (err)
203 return err;
204
205 for_each_node_with_cpus(node) {
206 /* some architectures (e.g. SN2) have cpuless nodes */
207 BUG_ON(pidx > maxpools);
208 m->to_pool[node] = pidx;
209 m->pool_to[pidx] = node;
210 pidx++;
211 }
212 /* nodes brought online later all get mapped to pool0, sorry */
213
214 return pidx;
215}
216
217
218/*
219 * Add a reference to the global map of cpus to pools (and
220 * vice versa). Initialise the map if we're the first user.
221 * Returns the number of pools.
222 */
223unsigned int
224svc_pool_map_get(void)
225{
226 struct svc_pool_map *m = &svc_pool_map;
227 int npools = -1;
228
229 mutex_lock(&svc_pool_map_mutex);
230
231 if (m->count++) {
232 mutex_unlock(&svc_pool_map_mutex);
233 return m->npools;
234 }
235
236 if (m->mode == SVC_POOL_AUTO)
237 m->mode = svc_pool_map_choose_mode();
238
239 switch (m->mode) {
240 case SVC_POOL_PERCPU:
241 npools = svc_pool_map_init_percpu(m);
242 break;
243 case SVC_POOL_PERNODE:
244 npools = svc_pool_map_init_pernode(m);
245 break;
246 }
247
248 if (npools < 0) {
249 /* default, or memory allocation failure */
250 npools = 1;
251 m->mode = SVC_POOL_GLOBAL;
252 }
253 m->npools = npools;
254
255 mutex_unlock(&svc_pool_map_mutex);
256 return m->npools;
257}
258EXPORT_SYMBOL_GPL(svc_pool_map_get);
259
260/*
261 * Drop a reference to the global map of cpus to pools.
262 * When the last reference is dropped, the map data is
263 * freed; this allows the sysadmin to change the pool
264 * mode using the pool_mode module option without
265 * rebooting or re-loading sunrpc.ko.
266 */
267void
268svc_pool_map_put(void)
269{
270 struct svc_pool_map *m = &svc_pool_map;
271
272 mutex_lock(&svc_pool_map_mutex);
273
274 if (!--m->count) {
275 kfree(m->to_pool);
276 m->to_pool = NULL;
277 kfree(m->pool_to);
278 m->pool_to = NULL;
279 m->npools = 0;
280 }
281
282 mutex_unlock(&svc_pool_map_mutex);
283}
284EXPORT_SYMBOL_GPL(svc_pool_map_put);
285
286static int svc_pool_map_get_node(unsigned int pidx)
287{
288 const struct svc_pool_map *m = &svc_pool_map;
289
290 if (m->count) {
291 if (m->mode == SVC_POOL_PERCPU)
292 return cpu_to_node(m->pool_to[pidx]);
293 if (m->mode == SVC_POOL_PERNODE)
294 return m->pool_to[pidx];
295 }
296 return NUMA_NO_NODE;
297}
298/*
299 * Set the given thread's cpus_allowed mask so that it
300 * will only run on cpus in the given pool.
301 */
302static inline void
303svc_pool_map_set_cpumask(struct task_struct *task, unsigned int pidx)
304{
305 struct svc_pool_map *m = &svc_pool_map;
306 unsigned int node = m->pool_to[pidx];
307
308 /*
309 * The caller checks for sv_nrpools > 1, which
310 * implies that we've been initialized.
311 */
312 WARN_ON_ONCE(m->count == 0);
313 if (m->count == 0)
314 return;
315
316 switch (m->mode) {
317 case SVC_POOL_PERCPU:
318 {
319 set_cpus_allowed_ptr(task, cpumask_of(node));
320 break;
321 }
322 case SVC_POOL_PERNODE:
323 {
324 set_cpus_allowed_ptr(task, cpumask_of_node(node));
325 break;
326 }
327 }
328}
329
330/*
331 * Use the mapping mode to choose a pool for a given CPU.
332 * Used when enqueueing an incoming RPC. Always returns
333 * a non-NULL pool pointer.
334 */
335struct svc_pool *
336svc_pool_for_cpu(struct svc_serv *serv, int cpu)
337{
338 struct svc_pool_map *m = &svc_pool_map;
339 unsigned int pidx = 0;
340
341 /*
342 * An uninitialised map happens in a pure client when
343 * lockd is brought up, so silently treat it the
344 * same as SVC_POOL_GLOBAL.
345 */
346 if (svc_serv_is_pooled(serv)) {
347 switch (m->mode) {
348 case SVC_POOL_PERCPU:
349 pidx = m->to_pool[cpu];
350 break;
351 case SVC_POOL_PERNODE:
352 pidx = m->to_pool[cpu_to_node(cpu)];
353 break;
354 }
355 }
356 return &serv->sv_pools[pidx % serv->sv_nrpools];
357}
358
359int svc_rpcb_setup(struct svc_serv *serv, struct net *net)
360{
361 int err;
362
363 err = rpcb_create_local(net);
364 if (err)
365 return err;
366
367 /* Remove any stale portmap registrations */
368 svc_unregister(serv, net);
369 return 0;
370}
371EXPORT_SYMBOL_GPL(svc_rpcb_setup);
372
373void svc_rpcb_cleanup(struct svc_serv *serv, struct net *net)
374{
375 svc_unregister(serv, net);
376 rpcb_put_local(net);
377}
378EXPORT_SYMBOL_GPL(svc_rpcb_cleanup);
379
380static int svc_uses_rpcbind(struct svc_serv *serv)
381{
382 struct svc_program *progp;
383 unsigned int i;
384
385 for (progp = serv->sv_program; progp; progp = progp->pg_next) {
386 for (i = 0; i < progp->pg_nvers; i++) {
387 if (progp->pg_vers[i] == NULL)
388 continue;
389 if (!progp->pg_vers[i]->vs_hidden)
390 return 1;
391 }
392 }
393
394 return 0;
395}
396
397int svc_bind(struct svc_serv *serv, struct net *net)
398{
399 if (!svc_uses_rpcbind(serv))
400 return 0;
401 return svc_rpcb_setup(serv, net);
402}
403EXPORT_SYMBOL_GPL(svc_bind);
404
405#if defined(CONFIG_SUNRPC_BACKCHANNEL)
406static void
407__svc_init_bc(struct svc_serv *serv)
408{
409 INIT_LIST_HEAD(&serv->sv_cb_list);
410 spin_lock_init(&serv->sv_cb_lock);
411 init_waitqueue_head(&serv->sv_cb_waitq);
412}
413#else
414static void
415__svc_init_bc(struct svc_serv *serv)
416{
417}
418#endif
419
420/*
421 * Create an RPC service
422 */
423static struct svc_serv *
424__svc_create(struct svc_program *prog, unsigned int bufsize, int npools,
425 const struct svc_serv_ops *ops)
426{
427 struct svc_serv *serv;
428 unsigned int vers;
429 unsigned int xdrsize;
430 unsigned int i;
431
432 if (!(serv = kzalloc(sizeof(*serv), GFP_KERNEL)))
433 return NULL;
434 serv->sv_name = prog->pg_name;
435 serv->sv_program = prog;
436 serv->sv_nrthreads = 1;
437 serv->sv_stats = prog->pg_stats;
438 if (bufsize > RPCSVC_MAXPAYLOAD)
439 bufsize = RPCSVC_MAXPAYLOAD;
440 serv->sv_max_payload = bufsize? bufsize : 4096;
441 serv->sv_max_mesg = roundup(serv->sv_max_payload + PAGE_SIZE, PAGE_SIZE);
442 serv->sv_ops = ops;
443 xdrsize = 0;
444 while (prog) {
445 prog->pg_lovers = prog->pg_nvers-1;
446 for (vers=0; vers<prog->pg_nvers ; vers++)
447 if (prog->pg_vers[vers]) {
448 prog->pg_hivers = vers;
449 if (prog->pg_lovers > vers)
450 prog->pg_lovers = vers;
451 if (prog->pg_vers[vers]->vs_xdrsize > xdrsize)
452 xdrsize = prog->pg_vers[vers]->vs_xdrsize;
453 }
454 prog = prog->pg_next;
455 }
456 serv->sv_xdrsize = xdrsize;
457 INIT_LIST_HEAD(&serv->sv_tempsocks);
458 INIT_LIST_HEAD(&serv->sv_permsocks);
459 timer_setup(&serv->sv_temptimer, NULL, 0);
460 spin_lock_init(&serv->sv_lock);
461
462 __svc_init_bc(serv);
463
464 serv->sv_nrpools = npools;
465 serv->sv_pools =
466 kcalloc(serv->sv_nrpools, sizeof(struct svc_pool),
467 GFP_KERNEL);
468 if (!serv->sv_pools) {
469 kfree(serv);
470 return NULL;
471 }
472
473 for (i = 0; i < serv->sv_nrpools; i++) {
474 struct svc_pool *pool = &serv->sv_pools[i];
475
476 dprintk("svc: initialising pool %u for %s\n",
477 i, serv->sv_name);
478
479 pool->sp_id = i;
480 INIT_LIST_HEAD(&pool->sp_sockets);
481 INIT_LIST_HEAD(&pool->sp_all_threads);
482 spin_lock_init(&pool->sp_lock);
483 }
484
485 return serv;
486}
487
488struct svc_serv *
489svc_create(struct svc_program *prog, unsigned int bufsize,
490 const struct svc_serv_ops *ops)
491{
492 return __svc_create(prog, bufsize, /*npools*/1, ops);
493}
494EXPORT_SYMBOL_GPL(svc_create);
495
496struct svc_serv *
497svc_create_pooled(struct svc_program *prog, unsigned int bufsize,
498 const struct svc_serv_ops *ops)
499{
500 struct svc_serv *serv;
501 unsigned int npools = svc_pool_map_get();
502
503 serv = __svc_create(prog, bufsize, npools, ops);
504 if (!serv)
505 goto out_err;
506 return serv;
507out_err:
508 svc_pool_map_put();
509 return NULL;
510}
511EXPORT_SYMBOL_GPL(svc_create_pooled);
512
513void svc_shutdown_net(struct svc_serv *serv, struct net *net)
514{
515 svc_close_net(serv, net);
516
517 if (serv->sv_ops->svo_shutdown)
518 serv->sv_ops->svo_shutdown(serv, net);
519}
520EXPORT_SYMBOL_GPL(svc_shutdown_net);
521
522/*
523 * Destroy an RPC service. Should be called with appropriate locking to
524 * protect the sv_nrthreads, sv_permsocks and sv_tempsocks.
525 */
526void
527svc_destroy(struct svc_serv *serv)
528{
529 dprintk("svc: svc_destroy(%s, %d)\n",
530 serv->sv_program->pg_name,
531 serv->sv_nrthreads);
532
533 if (serv->sv_nrthreads) {
534 if (--(serv->sv_nrthreads) != 0) {
535 svc_sock_update_bufs(serv);
536 return;
537 }
538 } else
539 printk("svc_destroy: no threads for serv=%p!\n", serv);
540
541 del_timer_sync(&serv->sv_temptimer);
542
543 /*
544 * The last user is gone and thus all sockets have to be destroyed to
545 * the point. Check this.
546 */
547 BUG_ON(!list_empty(&serv->sv_permsocks));
548 BUG_ON(!list_empty(&serv->sv_tempsocks));
549
550 cache_clean_deferred(serv);
551
552 if (svc_serv_is_pooled(serv))
553 svc_pool_map_put();
554
555 kfree(serv->sv_pools);
556 kfree(serv);
557}
558EXPORT_SYMBOL_GPL(svc_destroy);
559
560/*
561 * Allocate an RPC server's buffer space.
562 * We allocate pages and place them in rq_argpages.
563 */
564static int
565svc_init_buffer(struct svc_rqst *rqstp, unsigned int size, int node)
566{
567 unsigned int pages, arghi;
568
569 /* bc_xprt uses fore channel allocated buffers */
570 if (svc_is_backchannel(rqstp))
571 return 1;
572
573 pages = size / PAGE_SIZE + 1; /* extra page as we hold both request and reply.
574 * We assume one is at most one page
575 */
576 arghi = 0;
577 WARN_ON_ONCE(pages > RPCSVC_MAXPAGES);
578 if (pages > RPCSVC_MAXPAGES)
579 pages = RPCSVC_MAXPAGES;
580 while (pages) {
581 struct page *p = alloc_pages_node(node, GFP_KERNEL, 0);
582 if (!p)
583 break;
584 rqstp->rq_pages[arghi++] = p;
585 pages--;
586 }
587 return pages == 0;
588}
589
590/*
591 * Release an RPC server buffer
592 */
593static void
594svc_release_buffer(struct svc_rqst *rqstp)
595{
596 unsigned int i;
597
598 for (i = 0; i < ARRAY_SIZE(rqstp->rq_pages); i++)
599 if (rqstp->rq_pages[i])
600 put_page(rqstp->rq_pages[i]);
601}
602
603struct svc_rqst *
604svc_rqst_alloc(struct svc_serv *serv, struct svc_pool *pool, int node)
605{
606 struct svc_rqst *rqstp;
607
608 rqstp = kzalloc_node(sizeof(*rqstp), GFP_KERNEL, node);
609 if (!rqstp)
610 return rqstp;
611
612 __set_bit(RQ_BUSY, &rqstp->rq_flags);
613 spin_lock_init(&rqstp->rq_lock);
614 rqstp->rq_server = serv;
615 rqstp->rq_pool = pool;
616
617 rqstp->rq_argp = kmalloc_node(serv->sv_xdrsize, GFP_KERNEL, node);
618 if (!rqstp->rq_argp)
619 goto out_enomem;
620
621 rqstp->rq_resp = kmalloc_node(serv->sv_xdrsize, GFP_KERNEL, node);
622 if (!rqstp->rq_resp)
623 goto out_enomem;
624
625 if (!svc_init_buffer(rqstp, serv->sv_max_mesg, node))
626 goto out_enomem;
627
628 return rqstp;
629out_enomem:
630 svc_rqst_free(rqstp);
631 return NULL;
632}
633EXPORT_SYMBOL_GPL(svc_rqst_alloc);
634
635struct svc_rqst *
636svc_prepare_thread(struct svc_serv *serv, struct svc_pool *pool, int node)
637{
638 struct svc_rqst *rqstp;
639
640 rqstp = svc_rqst_alloc(serv, pool, node);
641 if (!rqstp)
642 return ERR_PTR(-ENOMEM);
643
644 serv->sv_nrthreads++;
645 spin_lock_bh(&pool->sp_lock);
646 pool->sp_nrthreads++;
647 list_add_rcu(&rqstp->rq_all, &pool->sp_all_threads);
648 spin_unlock_bh(&pool->sp_lock);
649 return rqstp;
650}
651EXPORT_SYMBOL_GPL(svc_prepare_thread);
652
653/*
654 * Choose a pool in which to create a new thread, for svc_set_num_threads
655 */
656static inline struct svc_pool *
657choose_pool(struct svc_serv *serv, struct svc_pool *pool, unsigned int *state)
658{
659 if (pool != NULL)
660 return pool;
661
662 return &serv->sv_pools[(*state)++ % serv->sv_nrpools];
663}
664
665/*
666 * Choose a thread to kill, for svc_set_num_threads
667 */
668static inline struct task_struct *
669choose_victim(struct svc_serv *serv, struct svc_pool *pool, unsigned int *state)
670{
671 unsigned int i;
672 struct task_struct *task = NULL;
673
674 if (pool != NULL) {
675 spin_lock_bh(&pool->sp_lock);
676 } else {
677 /* choose a pool in round-robin fashion */
678 for (i = 0; i < serv->sv_nrpools; i++) {
679 pool = &serv->sv_pools[--(*state) % serv->sv_nrpools];
680 spin_lock_bh(&pool->sp_lock);
681 if (!list_empty(&pool->sp_all_threads))
682 goto found_pool;
683 spin_unlock_bh(&pool->sp_lock);
684 }
685 return NULL;
686 }
687
688found_pool:
689 if (!list_empty(&pool->sp_all_threads)) {
690 struct svc_rqst *rqstp;
691
692 /*
693 * Remove from the pool->sp_all_threads list
694 * so we don't try to kill it again.
695 */
696 rqstp = list_entry(pool->sp_all_threads.next, struct svc_rqst, rq_all);
697 set_bit(RQ_VICTIM, &rqstp->rq_flags);
698 list_del_rcu(&rqstp->rq_all);
699 task = rqstp->rq_task;
700 }
701 spin_unlock_bh(&pool->sp_lock);
702
703 return task;
704}
705
706/* create new threads */
707static int
708svc_start_kthreads(struct svc_serv *serv, struct svc_pool *pool, int nrservs)
709{
710 struct svc_rqst *rqstp;
711 struct task_struct *task;
712 struct svc_pool *chosen_pool;
713 unsigned int state = serv->sv_nrthreads-1;
714 int node;
715
716 do {
717 nrservs--;
718 chosen_pool = choose_pool(serv, pool, &state);
719
720 node = svc_pool_map_get_node(chosen_pool->sp_id);
721 rqstp = svc_prepare_thread(serv, chosen_pool, node);
722 if (IS_ERR(rqstp))
723 return PTR_ERR(rqstp);
724
725 __module_get(serv->sv_ops->svo_module);
726 task = kthread_create_on_node(serv->sv_ops->svo_function, rqstp,
727 node, "%s", serv->sv_name);
728 if (IS_ERR(task)) {
729 module_put(serv->sv_ops->svo_module);
730 svc_exit_thread(rqstp);
731 return PTR_ERR(task);
732 }
733
734 rqstp->rq_task = task;
735 if (serv->sv_nrpools > 1)
736 svc_pool_map_set_cpumask(task, chosen_pool->sp_id);
737
738 svc_sock_update_bufs(serv);
739 wake_up_process(task);
740 } while (nrservs > 0);
741
742 return 0;
743}
744
745
746/* destroy old threads */
747static int
748svc_signal_kthreads(struct svc_serv *serv, struct svc_pool *pool, int nrservs)
749{
750 struct task_struct *task;
751 unsigned int state = serv->sv_nrthreads-1;
752
753 /* destroy old threads */
754 do {
755 task = choose_victim(serv, pool, &state);
756 if (task == NULL)
757 break;
758 send_sig(SIGINT, task, 1);
759 nrservs++;
760 } while (nrservs < 0);
761
762 return 0;
763}
764
765/*
766 * Create or destroy enough new threads to make the number
767 * of threads the given number. If `pool' is non-NULL, applies
768 * only to threads in that pool, otherwise round-robins between
769 * all pools. Caller must ensure that mutual exclusion between this and
770 * server startup or shutdown.
771 *
772 * Destroying threads relies on the service threads filling in
773 * rqstp->rq_task, which only the nfs ones do. Assumes the serv
774 * has been created using svc_create_pooled().
775 *
776 * Based on code that used to be in nfsd_svc() but tweaked
777 * to be pool-aware.
778 */
779int
780svc_set_num_threads(struct svc_serv *serv, struct svc_pool *pool, int nrservs)
781{
782 if (pool == NULL) {
783 /* The -1 assumes caller has done a svc_get() */
784 nrservs -= (serv->sv_nrthreads-1);
785 } else {
786 spin_lock_bh(&pool->sp_lock);
787 nrservs -= pool->sp_nrthreads;
788 spin_unlock_bh(&pool->sp_lock);
789 }
790
791 if (nrservs > 0)
792 return svc_start_kthreads(serv, pool, nrservs);
793 if (nrservs < 0)
794 return svc_signal_kthreads(serv, pool, nrservs);
795 return 0;
796}
797EXPORT_SYMBOL_GPL(svc_set_num_threads);
798
799/* destroy old threads */
800static int
801svc_stop_kthreads(struct svc_serv *serv, struct svc_pool *pool, int nrservs)
802{
803 struct task_struct *task;
804 unsigned int state = serv->sv_nrthreads-1;
805
806 /* destroy old threads */
807 do {
808 task = choose_victim(serv, pool, &state);
809 if (task == NULL)
810 break;
811 kthread_stop(task);
812 nrservs++;
813 } while (nrservs < 0);
814 return 0;
815}
816
817int
818svc_set_num_threads_sync(struct svc_serv *serv, struct svc_pool *pool, int nrservs)
819{
820 if (pool == NULL) {
821 /* The -1 assumes caller has done a svc_get() */
822 nrservs -= (serv->sv_nrthreads-1);
823 } else {
824 spin_lock_bh(&pool->sp_lock);
825 nrservs -= pool->sp_nrthreads;
826 spin_unlock_bh(&pool->sp_lock);
827 }
828
829 if (nrservs > 0)
830 return svc_start_kthreads(serv, pool, nrservs);
831 if (nrservs < 0)
832 return svc_stop_kthreads(serv, pool, nrservs);
833 return 0;
834}
835EXPORT_SYMBOL_GPL(svc_set_num_threads_sync);
836
837/*
838 * Called from a server thread as it's exiting. Caller must hold the "service
839 * mutex" for the service.
840 */
841void
842svc_rqst_free(struct svc_rqst *rqstp)
843{
844 svc_release_buffer(rqstp);
845 kfree(rqstp->rq_resp);
846 kfree(rqstp->rq_argp);
847 kfree(rqstp->rq_auth_data);
848 kfree_rcu(rqstp, rq_rcu_head);
849}
850EXPORT_SYMBOL_GPL(svc_rqst_free);
851
852void
853svc_exit_thread(struct svc_rqst *rqstp)
854{
855 struct svc_serv *serv = rqstp->rq_server;
856 struct svc_pool *pool = rqstp->rq_pool;
857
858 spin_lock_bh(&pool->sp_lock);
859 pool->sp_nrthreads--;
860 if (!test_and_set_bit(RQ_VICTIM, &rqstp->rq_flags))
861 list_del_rcu(&rqstp->rq_all);
862 spin_unlock_bh(&pool->sp_lock);
863
864 svc_rqst_free(rqstp);
865
866 /* Release the server */
867 if (serv)
868 svc_destroy(serv);
869}
870EXPORT_SYMBOL_GPL(svc_exit_thread);
871
872/*
873 * Register an "inet" protocol family netid with the local
874 * rpcbind daemon via an rpcbind v4 SET request.
875 *
876 * No netconfig infrastructure is available in the kernel, so
877 * we map IP_ protocol numbers to netids by hand.
878 *
879 * Returns zero on success; a negative errno value is returned
880 * if any error occurs.
881 */
882static int __svc_rpcb_register4(struct net *net, const u32 program,
883 const u32 version,
884 const unsigned short protocol,
885 const unsigned short port)
886{
887 const struct sockaddr_in sin = {
888 .sin_family = AF_INET,
889 .sin_addr.s_addr = htonl(INADDR_ANY),
890 .sin_port = htons(port),
891 };
892 const char *netid;
893 int error;
894
895 switch (protocol) {
896 case IPPROTO_UDP:
897 netid = RPCBIND_NETID_UDP;
898 break;
899 case IPPROTO_TCP:
900 netid = RPCBIND_NETID_TCP;
901 break;
902 default:
903 return -ENOPROTOOPT;
904 }
905
906 error = rpcb_v4_register(net, program, version,
907 (const struct sockaddr *)&sin, netid);
908
909 /*
910 * User space didn't support rpcbind v4, so retry this
911 * registration request with the legacy rpcbind v2 protocol.
912 */
913 if (error == -EPROTONOSUPPORT)
914 error = rpcb_register(net, program, version, protocol, port);
915
916 return error;
917}
918
919#if IS_ENABLED(CONFIG_IPV6)
920/*
921 * Register an "inet6" protocol family netid with the local
922 * rpcbind daemon via an rpcbind v4 SET request.
923 *
924 * No netconfig infrastructure is available in the kernel, so
925 * we map IP_ protocol numbers to netids by hand.
926 *
927 * Returns zero on success; a negative errno value is returned
928 * if any error occurs.
929 */
930static int __svc_rpcb_register6(struct net *net, const u32 program,
931 const u32 version,
932 const unsigned short protocol,
933 const unsigned short port)
934{
935 const struct sockaddr_in6 sin6 = {
936 .sin6_family = AF_INET6,
937 .sin6_addr = IN6ADDR_ANY_INIT,
938 .sin6_port = htons(port),
939 };
940 const char *netid;
941 int error;
942
943 switch (protocol) {
944 case IPPROTO_UDP:
945 netid = RPCBIND_NETID_UDP6;
946 break;
947 case IPPROTO_TCP:
948 netid = RPCBIND_NETID_TCP6;
949 break;
950 default:
951 return -ENOPROTOOPT;
952 }
953
954 error = rpcb_v4_register(net, program, version,
955 (const struct sockaddr *)&sin6, netid);
956
957 /*
958 * User space didn't support rpcbind version 4, so we won't
959 * use a PF_INET6 listener.
960 */
961 if (error == -EPROTONOSUPPORT)
962 error = -EAFNOSUPPORT;
963
964 return error;
965}
966#endif /* IS_ENABLED(CONFIG_IPV6) */
967
968/*
969 * Register a kernel RPC service via rpcbind version 4.
970 *
971 * Returns zero on success; a negative errno value is returned
972 * if any error occurs.
973 */
974static int __svc_register(struct net *net, const char *progname,
975 const u32 program, const u32 version,
976 const int family,
977 const unsigned short protocol,
978 const unsigned short port)
979{
980 int error = -EAFNOSUPPORT;
981
982 switch (family) {
983 case PF_INET:
984 error = __svc_rpcb_register4(net, program, version,
985 protocol, port);
986 break;
987#if IS_ENABLED(CONFIG_IPV6)
988 case PF_INET6:
989 error = __svc_rpcb_register6(net, program, version,
990 protocol, port);
991#endif
992 }
993
994 return error;
995}
996
997int svc_rpcbind_set_version(struct net *net,
998 const struct svc_program *progp,
999 u32 version, int family,
1000 unsigned short proto,
1001 unsigned short port)
1002{
1003 dprintk("svc: svc_register(%sv%d, %s, %u, %u)\n",
1004 progp->pg_name, version,
1005 proto == IPPROTO_UDP? "udp" : "tcp",
1006 port, family);
1007
1008 return __svc_register(net, progp->pg_name, progp->pg_prog,
1009 version, family, proto, port);
1010
1011}
1012EXPORT_SYMBOL_GPL(svc_rpcbind_set_version);
1013
1014int svc_generic_rpcbind_set(struct net *net,
1015 const struct svc_program *progp,
1016 u32 version, int family,
1017 unsigned short proto,
1018 unsigned short port)
1019{
1020 const struct svc_version *vers = progp->pg_vers[version];
1021 int error;
1022
1023 if (vers == NULL)
1024 return 0;
1025
1026 if (vers->vs_hidden) {
1027 dprintk("svc: svc_register(%sv%d, %s, %u, %u)"
1028 " (but not telling portmap)\n",
1029 progp->pg_name, version,
1030 proto == IPPROTO_UDP? "udp" : "tcp",
1031 port, family);
1032 return 0;
1033 }
1034
1035 /*
1036 * Don't register a UDP port if we need congestion
1037 * control.
1038 */
1039 if (vers->vs_need_cong_ctrl && proto == IPPROTO_UDP)
1040 return 0;
1041
1042 error = svc_rpcbind_set_version(net, progp, version,
1043 family, proto, port);
1044
1045 return (vers->vs_rpcb_optnl) ? 0 : error;
1046}
1047EXPORT_SYMBOL_GPL(svc_generic_rpcbind_set);
1048
1049/**
1050 * svc_register - register an RPC service with the local portmapper
1051 * @serv: svc_serv struct for the service to register
1052 * @net: net namespace for the service to register
1053 * @family: protocol family of service's listener socket
1054 * @proto: transport protocol number to advertise
1055 * @port: port to advertise
1056 *
1057 * Service is registered for any address in the passed-in protocol family
1058 */
1059int svc_register(const struct svc_serv *serv, struct net *net,
1060 const int family, const unsigned short proto,
1061 const unsigned short port)
1062{
1063 struct svc_program *progp;
1064 unsigned int i;
1065 int error = 0;
1066
1067 WARN_ON_ONCE(proto == 0 && port == 0);
1068 if (proto == 0 && port == 0)
1069 return -EINVAL;
1070
1071 for (progp = serv->sv_program; progp; progp = progp->pg_next) {
1072 for (i = 0; i < progp->pg_nvers; i++) {
1073
1074 error = progp->pg_rpcbind_set(net, progp, i,
1075 family, proto, port);
1076 if (error < 0) {
1077 printk(KERN_WARNING "svc: failed to register "
1078 "%sv%u RPC service (errno %d).\n",
1079 progp->pg_name, i, -error);
1080 break;
1081 }
1082 }
1083 }
1084
1085 return error;
1086}
1087
1088/*
1089 * If user space is running rpcbind, it should take the v4 UNSET
1090 * and clear everything for this [program, version]. If user space
1091 * is running portmap, it will reject the v4 UNSET, but won't have
1092 * any "inet6" entries anyway. So a PMAP_UNSET should be sufficient
1093 * in this case to clear all existing entries for [program, version].
1094 */
1095static void __svc_unregister(struct net *net, const u32 program, const u32 version,
1096 const char *progname)
1097{
1098 int error;
1099
1100 error = rpcb_v4_register(net, program, version, NULL, "");
1101
1102 /*
1103 * User space didn't support rpcbind v4, so retry this
1104 * request with the legacy rpcbind v2 protocol.
1105 */
1106 if (error == -EPROTONOSUPPORT)
1107 error = rpcb_register(net, program, version, 0, 0);
1108
1109 dprintk("svc: %s(%sv%u), error %d\n",
1110 __func__, progname, version, error);
1111}
1112
1113/*
1114 * All netids, bind addresses and ports registered for [program, version]
1115 * are removed from the local rpcbind database (if the service is not
1116 * hidden) to make way for a new instance of the service.
1117 *
1118 * The result of unregistration is reported via dprintk for those who want
1119 * verification of the result, but is otherwise not important.
1120 */
1121static void svc_unregister(const struct svc_serv *serv, struct net *net)
1122{
1123 struct svc_program *progp;
1124 unsigned long flags;
1125 unsigned int i;
1126
1127 clear_thread_flag(TIF_SIGPENDING);
1128
1129 for (progp = serv->sv_program; progp; progp = progp->pg_next) {
1130 for (i = 0; i < progp->pg_nvers; i++) {
1131 if (progp->pg_vers[i] == NULL)
1132 continue;
1133 if (progp->pg_vers[i]->vs_hidden)
1134 continue;
1135
1136 dprintk("svc: attempting to unregister %sv%u\n",
1137 progp->pg_name, i);
1138 __svc_unregister(net, progp->pg_prog, i, progp->pg_name);
1139 }
1140 }
1141
1142 spin_lock_irqsave(¤t->sighand->siglock, flags);
1143 recalc_sigpending();
1144 spin_unlock_irqrestore(¤t->sighand->siglock, flags);
1145}
1146
1147/*
1148 * dprintk the given error with the address of the client that caused it.
1149 */
1150#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
1151static __printf(2, 3)
1152void svc_printk(struct svc_rqst *rqstp, const char *fmt, ...)
1153{
1154 struct va_format vaf;
1155 va_list args;
1156 char buf[RPC_MAX_ADDRBUFLEN];
1157
1158 va_start(args, fmt);
1159
1160 vaf.fmt = fmt;
1161 vaf.va = &args;
1162
1163 dprintk("svc: %s: %pV", svc_print_addr(rqstp, buf, sizeof(buf)), &vaf);
1164
1165 va_end(args);
1166}
1167#else
1168static __printf(2,3) void svc_printk(struct svc_rqst *rqstp, const char *fmt, ...) {}
1169#endif
1170
1171__be32
1172svc_return_autherr(struct svc_rqst *rqstp, __be32 auth_err)
1173{
1174 set_bit(RQ_AUTHERR, &rqstp->rq_flags);
1175 return auth_err;
1176}
1177EXPORT_SYMBOL_GPL(svc_return_autherr);
1178
1179static __be32
1180svc_get_autherr(struct svc_rqst *rqstp, __be32 *statp)
1181{
1182 if (test_and_clear_bit(RQ_AUTHERR, &rqstp->rq_flags))
1183 return *statp;
1184 return rpc_auth_ok;
1185}
1186
1187static int
1188svc_generic_dispatch(struct svc_rqst *rqstp, __be32 *statp)
1189{
1190 struct kvec *argv = &rqstp->rq_arg.head[0];
1191 struct kvec *resv = &rqstp->rq_res.head[0];
1192 const struct svc_procedure *procp = rqstp->rq_procinfo;
1193
1194 /*
1195 * Decode arguments
1196 * XXX: why do we ignore the return value?
1197 */
1198 if (procp->pc_decode &&
1199 !procp->pc_decode(rqstp, argv->iov_base)) {
1200 *statp = rpc_garbage_args;
1201 return 1;
1202 }
1203
1204 *statp = procp->pc_func(rqstp);
1205
1206 if (*statp == rpc_drop_reply ||
1207 test_bit(RQ_DROPME, &rqstp->rq_flags))
1208 return 0;
1209
1210 if (test_bit(RQ_AUTHERR, &rqstp->rq_flags))
1211 return 1;
1212
1213 if (*statp != rpc_success)
1214 return 1;
1215
1216 /* Encode reply */
1217 if (procp->pc_encode &&
1218 !procp->pc_encode(rqstp, resv->iov_base + resv->iov_len)) {
1219 dprintk("svc: failed to encode reply\n");
1220 /* serv->sv_stats->rpcsystemerr++; */
1221 *statp = rpc_system_err;
1222 }
1223 return 1;
1224}
1225
1226__be32
1227svc_generic_init_request(struct svc_rqst *rqstp,
1228 const struct svc_program *progp,
1229 struct svc_process_info *ret)
1230{
1231 const struct svc_version *versp = NULL; /* compiler food */
1232 const struct svc_procedure *procp = NULL;
1233
1234 if (rqstp->rq_vers >= progp->pg_nvers )
1235 goto err_bad_vers;
1236 versp = progp->pg_vers[rqstp->rq_vers];
1237 if (!versp)
1238 goto err_bad_vers;
1239
1240 /*
1241 * Some protocol versions (namely NFSv4) require some form of
1242 * congestion control. (See RFC 7530 section 3.1 paragraph 2)
1243 * In other words, UDP is not allowed. We mark those when setting
1244 * up the svc_xprt, and verify that here.
1245 *
1246 * The spec is not very clear about what error should be returned
1247 * when someone tries to access a server that is listening on UDP
1248 * for lower versions. RPC_PROG_MISMATCH seems to be the closest
1249 * fit.
1250 */
1251 if (versp->vs_need_cong_ctrl && rqstp->rq_xprt &&
1252 !test_bit(XPT_CONG_CTRL, &rqstp->rq_xprt->xpt_flags))
1253 goto err_bad_vers;
1254
1255 if (rqstp->rq_proc >= versp->vs_nproc)
1256 goto err_bad_proc;
1257 rqstp->rq_procinfo = procp = &versp->vs_proc[rqstp->rq_proc];
1258 if (!procp)
1259 goto err_bad_proc;
1260
1261 /* Initialize storage for argp and resp */
1262 memset(rqstp->rq_argp, 0, procp->pc_argsize);
1263 memset(rqstp->rq_resp, 0, procp->pc_ressize);
1264
1265 /* Bump per-procedure stats counter */
1266 versp->vs_count[rqstp->rq_proc]++;
1267
1268 ret->dispatch = versp->vs_dispatch;
1269 return rpc_success;
1270err_bad_vers:
1271 ret->mismatch.lovers = progp->pg_lovers;
1272 ret->mismatch.hivers = progp->pg_hivers;
1273 return rpc_prog_mismatch;
1274err_bad_proc:
1275 return rpc_proc_unavail;
1276}
1277EXPORT_SYMBOL_GPL(svc_generic_init_request);
1278
1279/*
1280 * Common routine for processing the RPC request.
1281 */
1282static int
1283svc_process_common(struct svc_rqst *rqstp, struct kvec *argv, struct kvec *resv)
1284{
1285 struct svc_program *progp;
1286 const struct svc_procedure *procp = NULL;
1287 struct svc_serv *serv = rqstp->rq_server;
1288 struct svc_process_info process;
1289 __be32 *statp;
1290 u32 prog, vers;
1291 __be32 auth_stat, rpc_stat;
1292 int auth_res;
1293 __be32 *reply_statp;
1294
1295 rpc_stat = rpc_success;
1296
1297 if (argv->iov_len < 6*4)
1298 goto err_short_len;
1299
1300 /* Will be turned off by GSS integrity and privacy services */
1301 set_bit(RQ_SPLICE_OK, &rqstp->rq_flags);
1302 /* Will be turned off only when NFSv4 Sessions are used */
1303 set_bit(RQ_USEDEFERRAL, &rqstp->rq_flags);
1304 clear_bit(RQ_DROPME, &rqstp->rq_flags);
1305
1306 svc_putu32(resv, rqstp->rq_xid);
1307
1308 vers = svc_getnl(argv);
1309
1310 /* First words of reply: */
1311 svc_putnl(resv, 1); /* REPLY */
1312
1313 if (vers != 2) /* RPC version number */
1314 goto err_bad_rpc;
1315
1316 /* Save position in case we later decide to reject: */
1317 reply_statp = resv->iov_base + resv->iov_len;
1318
1319 svc_putnl(resv, 0); /* ACCEPT */
1320
1321 rqstp->rq_prog = prog = svc_getnl(argv); /* program number */
1322 rqstp->rq_vers = svc_getnl(argv); /* version number */
1323 rqstp->rq_proc = svc_getnl(argv); /* procedure number */
1324
1325 for (progp = serv->sv_program; progp; progp = progp->pg_next)
1326 if (prog == progp->pg_prog)
1327 break;
1328
1329 /*
1330 * Decode auth data, and add verifier to reply buffer.
1331 * We do this before anything else in order to get a decent
1332 * auth verifier.
1333 */
1334 auth_res = svc_authenticate(rqstp, &auth_stat);
1335 /* Also give the program a chance to reject this call: */
1336 if (auth_res == SVC_OK && progp) {
1337 auth_stat = rpc_autherr_badcred;
1338 auth_res = progp->pg_authenticate(rqstp);
1339 }
1340 switch (auth_res) {
1341 case SVC_OK:
1342 break;
1343 case SVC_GARBAGE:
1344 goto err_garbage;
1345 case SVC_SYSERR:
1346 rpc_stat = rpc_system_err;
1347 goto err_bad;
1348 case SVC_DENIED:
1349 goto err_bad_auth;
1350 case SVC_CLOSE:
1351 goto close;
1352 case SVC_DROP:
1353 goto dropit;
1354 case SVC_COMPLETE:
1355 goto sendit;
1356 }
1357
1358 if (progp == NULL)
1359 goto err_bad_prog;
1360
1361 rpc_stat = progp->pg_init_request(rqstp, progp, &process);
1362 switch (rpc_stat) {
1363 case rpc_success:
1364 break;
1365 case rpc_prog_unavail:
1366 goto err_bad_prog;
1367 case rpc_prog_mismatch:
1368 goto err_bad_vers;
1369 case rpc_proc_unavail:
1370 goto err_bad_proc;
1371 }
1372
1373 procp = rqstp->rq_procinfo;
1374 /* Should this check go into the dispatcher? */
1375 if (!procp || !procp->pc_func)
1376 goto err_bad_proc;
1377
1378 /* Syntactic check complete */
1379 serv->sv_stats->rpccnt++;
1380 trace_svc_process(rqstp, progp->pg_name);
1381
1382 /* Build the reply header. */
1383 statp = resv->iov_base +resv->iov_len;
1384 svc_putnl(resv, RPC_SUCCESS);
1385
1386 /* un-reserve some of the out-queue now that we have a
1387 * better idea of reply size
1388 */
1389 if (procp->pc_xdrressize)
1390 svc_reserve_auth(rqstp, procp->pc_xdrressize<<2);
1391
1392 /* Call the function that processes the request. */
1393 if (!process.dispatch) {
1394 if (!svc_generic_dispatch(rqstp, statp))
1395 goto release_dropit;
1396 if (*statp == rpc_garbage_args)
1397 goto err_garbage;
1398 auth_stat = svc_get_autherr(rqstp, statp);
1399 if (auth_stat != rpc_auth_ok)
1400 goto err_release_bad_auth;
1401 } else {
1402 dprintk("svc: calling dispatcher\n");
1403 if (!process.dispatch(rqstp, statp))
1404 goto release_dropit; /* Release reply info */
1405 }
1406
1407 /* Check RPC status result */
1408 if (*statp != rpc_success)
1409 resv->iov_len = ((void*)statp) - resv->iov_base + 4;
1410
1411 /* Release reply info */
1412 if (procp->pc_release)
1413 procp->pc_release(rqstp);
1414
1415 if (procp->pc_encode == NULL)
1416 goto dropit;
1417
1418 sendit:
1419 if (svc_authorise(rqstp))
1420 goto close;
1421 return 1; /* Caller can now send it */
1422
1423release_dropit:
1424 if (procp->pc_release)
1425 procp->pc_release(rqstp);
1426 dropit:
1427 svc_authorise(rqstp); /* doesn't hurt to call this twice */
1428 dprintk("svc: svc_process dropit\n");
1429 return 0;
1430
1431 close:
1432 if (rqstp->rq_xprt && test_bit(XPT_TEMP, &rqstp->rq_xprt->xpt_flags))
1433 svc_close_xprt(rqstp->rq_xprt);
1434 dprintk("svc: svc_process close\n");
1435 return 0;
1436
1437err_short_len:
1438 svc_printk(rqstp, "short len %zd, dropping request\n",
1439 argv->iov_len);
1440 goto close;
1441
1442err_bad_rpc:
1443 serv->sv_stats->rpcbadfmt++;
1444 svc_putnl(resv, 1); /* REJECT */
1445 svc_putnl(resv, 0); /* RPC_MISMATCH */
1446 svc_putnl(resv, 2); /* Only RPCv2 supported */
1447 svc_putnl(resv, 2);
1448 goto sendit;
1449
1450err_release_bad_auth:
1451 if (procp->pc_release)
1452 procp->pc_release(rqstp);
1453err_bad_auth:
1454 dprintk("svc: authentication failed (%d)\n", ntohl(auth_stat));
1455 serv->sv_stats->rpcbadauth++;
1456 /* Restore write pointer to location of accept status: */
1457 xdr_ressize_check(rqstp, reply_statp);
1458 svc_putnl(resv, 1); /* REJECT */
1459 svc_putnl(resv, 1); /* AUTH_ERROR */
1460 svc_putnl(resv, ntohl(auth_stat)); /* status */
1461 goto sendit;
1462
1463err_bad_prog:
1464 dprintk("svc: unknown program %d\n", prog);
1465 serv->sv_stats->rpcbadfmt++;
1466 svc_putnl(resv, RPC_PROG_UNAVAIL);
1467 goto sendit;
1468
1469err_bad_vers:
1470 svc_printk(rqstp, "unknown version (%d for prog %d, %s)\n",
1471 rqstp->rq_vers, rqstp->rq_prog, progp->pg_name);
1472
1473 serv->sv_stats->rpcbadfmt++;
1474 svc_putnl(resv, RPC_PROG_MISMATCH);
1475 svc_putnl(resv, process.mismatch.lovers);
1476 svc_putnl(resv, process.mismatch.hivers);
1477 goto sendit;
1478
1479err_bad_proc:
1480 svc_printk(rqstp, "unknown procedure (%d)\n", rqstp->rq_proc);
1481
1482 serv->sv_stats->rpcbadfmt++;
1483 svc_putnl(resv, RPC_PROC_UNAVAIL);
1484 goto sendit;
1485
1486err_garbage:
1487 svc_printk(rqstp, "failed to decode args\n");
1488
1489 rpc_stat = rpc_garbage_args;
1490err_bad:
1491 serv->sv_stats->rpcbadfmt++;
1492 svc_putnl(resv, ntohl(rpc_stat));
1493 goto sendit;
1494}
1495
1496/*
1497 * Process the RPC request.
1498 */
1499int
1500svc_process(struct svc_rqst *rqstp)
1501{
1502 struct kvec *argv = &rqstp->rq_arg.head[0];
1503 struct kvec *resv = &rqstp->rq_res.head[0];
1504 struct svc_serv *serv = rqstp->rq_server;
1505 u32 dir;
1506
1507 /*
1508 * Setup response xdr_buf.
1509 * Initially it has just one page
1510 */
1511 rqstp->rq_next_page = &rqstp->rq_respages[1];
1512 resv->iov_base = page_address(rqstp->rq_respages[0]);
1513 resv->iov_len = 0;
1514 rqstp->rq_res.pages = rqstp->rq_respages + 1;
1515 rqstp->rq_res.len = 0;
1516 rqstp->rq_res.page_base = 0;
1517 rqstp->rq_res.page_len = 0;
1518 rqstp->rq_res.buflen = PAGE_SIZE;
1519 rqstp->rq_res.tail[0].iov_base = NULL;
1520 rqstp->rq_res.tail[0].iov_len = 0;
1521
1522 dir = svc_getnl(argv);
1523 if (dir != 0) {
1524 /* direction != CALL */
1525 svc_printk(rqstp, "bad direction %d, dropping request\n", dir);
1526 serv->sv_stats->rpcbadfmt++;
1527 goto out_drop;
1528 }
1529
1530 /* Reserve space for the record marker */
1531 if (rqstp->rq_prot == IPPROTO_TCP)
1532 svc_putnl(resv, 0);
1533
1534 /* Returns 1 for send, 0 for drop */
1535 if (likely(svc_process_common(rqstp, argv, resv)))
1536 return svc_send(rqstp);
1537
1538out_drop:
1539 svc_drop(rqstp);
1540 return 0;
1541}
1542EXPORT_SYMBOL_GPL(svc_process);
1543
1544#if defined(CONFIG_SUNRPC_BACKCHANNEL)
1545/*
1546 * Process a backchannel RPC request that arrived over an existing
1547 * outbound connection
1548 */
1549int
1550bc_svc_process(struct svc_serv *serv, struct rpc_rqst *req,
1551 struct svc_rqst *rqstp)
1552{
1553 struct kvec *argv = &rqstp->rq_arg.head[0];
1554 struct kvec *resv = &rqstp->rq_res.head[0];
1555 struct rpc_task *task;
1556 int proc_error;
1557 int error;
1558
1559 dprintk("svc: %s(%p)\n", __func__, req);
1560
1561 /* Build the svc_rqst used by the common processing routine */
1562 rqstp->rq_xid = req->rq_xid;
1563 rqstp->rq_prot = req->rq_xprt->prot;
1564 rqstp->rq_server = serv;
1565 rqstp->rq_bc_net = req->rq_xprt->xprt_net;
1566
1567 rqstp->rq_addrlen = sizeof(req->rq_xprt->addr);
1568 memcpy(&rqstp->rq_addr, &req->rq_xprt->addr, rqstp->rq_addrlen);
1569 memcpy(&rqstp->rq_arg, &req->rq_rcv_buf, sizeof(rqstp->rq_arg));
1570 memcpy(&rqstp->rq_res, &req->rq_snd_buf, sizeof(rqstp->rq_res));
1571
1572 /* Adjust the argument buffer length */
1573 rqstp->rq_arg.len = req->rq_private_buf.len;
1574 if (rqstp->rq_arg.len <= rqstp->rq_arg.head[0].iov_len) {
1575 rqstp->rq_arg.head[0].iov_len = rqstp->rq_arg.len;
1576 rqstp->rq_arg.page_len = 0;
1577 } else if (rqstp->rq_arg.len <= rqstp->rq_arg.head[0].iov_len +
1578 rqstp->rq_arg.page_len)
1579 rqstp->rq_arg.page_len = rqstp->rq_arg.len -
1580 rqstp->rq_arg.head[0].iov_len;
1581 else
1582 rqstp->rq_arg.len = rqstp->rq_arg.head[0].iov_len +
1583 rqstp->rq_arg.page_len;
1584
1585 /* reset result send buffer "put" position */
1586 resv->iov_len = 0;
1587
1588 /*
1589 * Skip the next two words because they've already been
1590 * processed in the transport
1591 */
1592 svc_getu32(argv); /* XID */
1593 svc_getnl(argv); /* CALLDIR */
1594
1595 /* Parse and execute the bc call */
1596 proc_error = svc_process_common(rqstp, argv, resv);
1597
1598 atomic_dec(&req->rq_xprt->bc_slot_count);
1599 if (!proc_error) {
1600 /* Processing error: drop the request */
1601 xprt_free_bc_request(req);
1602 error = -EINVAL;
1603 goto out;
1604 }
1605 /* Finally, send the reply synchronously */
1606 memcpy(&req->rq_snd_buf, &rqstp->rq_res, sizeof(req->rq_snd_buf));
1607 task = rpc_run_bc_task(req);
1608 if (IS_ERR(task)) {
1609 error = PTR_ERR(task);
1610 goto out;
1611 }
1612
1613 WARN_ON_ONCE(atomic_read(&task->tk_count) != 1);
1614 error = task->tk_status;
1615 rpc_put_task(task);
1616
1617out:
1618 dprintk("svc: %s(), error=%d\n", __func__, error);
1619 return error;
1620}
1621EXPORT_SYMBOL_GPL(bc_svc_process);
1622#endif /* CONFIG_SUNRPC_BACKCHANNEL */
1623
1624/*
1625 * Return (transport-specific) limit on the rpc payload.
1626 */
1627u32 svc_max_payload(const struct svc_rqst *rqstp)
1628{
1629 u32 max = rqstp->rq_xprt->xpt_class->xcl_max_payload;
1630
1631 if (rqstp->rq_server->sv_max_payload < max)
1632 max = rqstp->rq_server->sv_max_payload;
1633 return max;
1634}
1635EXPORT_SYMBOL_GPL(svc_max_payload);
1636
1637/**
1638 * svc_fill_write_vector - Construct data argument for VFS write call
1639 * @rqstp: svc_rqst to operate on
1640 * @pages: list of pages containing data payload
1641 * @first: buffer containing first section of write payload
1642 * @total: total number of bytes of write payload
1643 *
1644 * Fills in rqstp::rq_vec, and returns the number of elements.
1645 */
1646unsigned int svc_fill_write_vector(struct svc_rqst *rqstp, struct page **pages,
1647 struct kvec *first, size_t total)
1648{
1649 struct kvec *vec = rqstp->rq_vec;
1650 unsigned int i;
1651
1652 /* Some types of transport can present the write payload
1653 * entirely in rq_arg.pages. In this case, @first is empty.
1654 */
1655 i = 0;
1656 if (first->iov_len) {
1657 vec[i].iov_base = first->iov_base;
1658 vec[i].iov_len = min_t(size_t, total, first->iov_len);
1659 total -= vec[i].iov_len;
1660 ++i;
1661 }
1662
1663 while (total) {
1664 vec[i].iov_base = page_address(*pages);
1665 vec[i].iov_len = min_t(size_t, total, PAGE_SIZE);
1666 total -= vec[i].iov_len;
1667 ++i;
1668 ++pages;
1669 }
1670
1671 WARN_ON_ONCE(i > ARRAY_SIZE(rqstp->rq_vec));
1672 return i;
1673}
1674EXPORT_SYMBOL_GPL(svc_fill_write_vector);
1675
1676/**
1677 * svc_fill_symlink_pathname - Construct pathname argument for VFS symlink call
1678 * @rqstp: svc_rqst to operate on
1679 * @first: buffer containing first section of pathname
1680 * @p: buffer containing remaining section of pathname
1681 * @total: total length of the pathname argument
1682 *
1683 * The VFS symlink API demands a NUL-terminated pathname in mapped memory.
1684 * Returns pointer to a NUL-terminated string, or an ERR_PTR. Caller must free
1685 * the returned string.
1686 */
1687char *svc_fill_symlink_pathname(struct svc_rqst *rqstp, struct kvec *first,
1688 void *p, size_t total)
1689{
1690 size_t len, remaining;
1691 char *result, *dst;
1692
1693 result = kmalloc(total + 1, GFP_KERNEL);
1694 if (!result)
1695 return ERR_PTR(-ESERVERFAULT);
1696
1697 dst = result;
1698 remaining = total;
1699
1700 len = min_t(size_t, total, first->iov_len);
1701 if (len) {
1702 memcpy(dst, first->iov_base, len);
1703 dst += len;
1704 remaining -= len;
1705 }
1706
1707 if (remaining) {
1708 len = min_t(size_t, remaining, PAGE_SIZE);
1709 memcpy(dst, p, len);
1710 dst += len;
1711 }
1712
1713 *dst = '\0';
1714
1715 /* Sanity check: Linux doesn't allow the pathname argument to
1716 * contain a NUL byte.
1717 */
1718 if (strlen(result) != total) {
1719 kfree(result);
1720 return ERR_PTR(-EINVAL);
1721 }
1722 return result;
1723}
1724EXPORT_SYMBOL_GPL(svc_fill_symlink_pathname);
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/signal.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, const 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, const 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)
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 const 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 timer_setup(&serv->sv_temptimer, NULL, 0);
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 const 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 const 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/* create new threads */
706static int
707svc_start_kthreads(struct svc_serv *serv, struct svc_pool *pool, int nrservs)
708{
709 struct svc_rqst *rqstp;
710 struct task_struct *task;
711 struct svc_pool *chosen_pool;
712 unsigned int state = serv->sv_nrthreads-1;
713 int node;
714
715 do {
716 nrservs--;
717 chosen_pool = choose_pool(serv, pool, &state);
718
719 node = svc_pool_map_get_node(chosen_pool->sp_id);
720 rqstp = svc_prepare_thread(serv, chosen_pool, node);
721 if (IS_ERR(rqstp))
722 return PTR_ERR(rqstp);
723
724 __module_get(serv->sv_ops->svo_module);
725 task = kthread_create_on_node(serv->sv_ops->svo_function, rqstp,
726 node, "%s", serv->sv_name);
727 if (IS_ERR(task)) {
728 module_put(serv->sv_ops->svo_module);
729 svc_exit_thread(rqstp);
730 return PTR_ERR(task);
731 }
732
733 rqstp->rq_task = task;
734 if (serv->sv_nrpools > 1)
735 svc_pool_map_set_cpumask(task, chosen_pool->sp_id);
736
737 svc_sock_update_bufs(serv);
738 wake_up_process(task);
739 } while (nrservs > 0);
740
741 return 0;
742}
743
744
745/* destroy old threads */
746static int
747svc_signal_kthreads(struct svc_serv *serv, struct svc_pool *pool, int nrservs)
748{
749 struct task_struct *task;
750 unsigned int state = serv->sv_nrthreads-1;
751
752 /* destroy old threads */
753 do {
754 task = choose_victim(serv, pool, &state);
755 if (task == NULL)
756 break;
757 send_sig(SIGINT, task, 1);
758 nrservs++;
759 } while (nrservs < 0);
760
761 return 0;
762}
763
764/*
765 * Create or destroy enough new threads to make the number
766 * of threads the given number. If `pool' is non-NULL, applies
767 * only to threads in that pool, otherwise round-robins between
768 * all pools. Caller must ensure that mutual exclusion between this and
769 * server startup or shutdown.
770 *
771 * Destroying threads relies on the service threads filling in
772 * rqstp->rq_task, which only the nfs ones do. Assumes the serv
773 * has been created using svc_create_pooled().
774 *
775 * Based on code that used to be in nfsd_svc() but tweaked
776 * to be pool-aware.
777 */
778int
779svc_set_num_threads(struct svc_serv *serv, struct svc_pool *pool, int nrservs)
780{
781 if (pool == NULL) {
782 /* The -1 assumes caller has done a svc_get() */
783 nrservs -= (serv->sv_nrthreads-1);
784 } else {
785 spin_lock_bh(&pool->sp_lock);
786 nrservs -= pool->sp_nrthreads;
787 spin_unlock_bh(&pool->sp_lock);
788 }
789
790 if (nrservs > 0)
791 return svc_start_kthreads(serv, pool, nrservs);
792 if (nrservs < 0)
793 return svc_signal_kthreads(serv, pool, nrservs);
794 return 0;
795}
796EXPORT_SYMBOL_GPL(svc_set_num_threads);
797
798/* destroy old threads */
799static int
800svc_stop_kthreads(struct svc_serv *serv, struct svc_pool *pool, int nrservs)
801{
802 struct task_struct *task;
803 unsigned int state = serv->sv_nrthreads-1;
804
805 /* destroy old threads */
806 do {
807 task = choose_victim(serv, pool, &state);
808 if (task == NULL)
809 break;
810 kthread_stop(task);
811 nrservs++;
812 } while (nrservs < 0);
813 return 0;
814}
815
816int
817svc_set_num_threads_sync(struct svc_serv *serv, struct svc_pool *pool, int nrservs)
818{
819 if (pool == NULL) {
820 /* The -1 assumes caller has done a svc_get() */
821 nrservs -= (serv->sv_nrthreads-1);
822 } else {
823 spin_lock_bh(&pool->sp_lock);
824 nrservs -= pool->sp_nrthreads;
825 spin_unlock_bh(&pool->sp_lock);
826 }
827
828 if (nrservs > 0)
829 return svc_start_kthreads(serv, pool, nrservs);
830 if (nrservs < 0)
831 return svc_stop_kthreads(serv, pool, nrservs);
832 return 0;
833}
834EXPORT_SYMBOL_GPL(svc_set_num_threads_sync);
835
836/*
837 * Called from a server thread as it's exiting. Caller must hold the "service
838 * mutex" for the service.
839 */
840void
841svc_rqst_free(struct svc_rqst *rqstp)
842{
843 svc_release_buffer(rqstp);
844 kfree(rqstp->rq_resp);
845 kfree(rqstp->rq_argp);
846 kfree(rqstp->rq_auth_data);
847 kfree_rcu(rqstp, rq_rcu_head);
848}
849EXPORT_SYMBOL_GPL(svc_rqst_free);
850
851void
852svc_exit_thread(struct svc_rqst *rqstp)
853{
854 struct svc_serv *serv = rqstp->rq_server;
855 struct svc_pool *pool = rqstp->rq_pool;
856
857 spin_lock_bh(&pool->sp_lock);
858 pool->sp_nrthreads--;
859 if (!test_and_set_bit(RQ_VICTIM, &rqstp->rq_flags))
860 list_del_rcu(&rqstp->rq_all);
861 spin_unlock_bh(&pool->sp_lock);
862
863 svc_rqst_free(rqstp);
864
865 /* Release the server */
866 if (serv)
867 svc_destroy(serv);
868}
869EXPORT_SYMBOL_GPL(svc_exit_thread);
870
871/*
872 * Register an "inet" protocol family netid with the local
873 * rpcbind daemon via an rpcbind v4 SET request.
874 *
875 * No netconfig infrastructure is available in the kernel, so
876 * we map IP_ protocol numbers to netids by hand.
877 *
878 * Returns zero on success; a negative errno value is returned
879 * if any error occurs.
880 */
881static int __svc_rpcb_register4(struct net *net, const u32 program,
882 const u32 version,
883 const unsigned short protocol,
884 const unsigned short port)
885{
886 const struct sockaddr_in sin = {
887 .sin_family = AF_INET,
888 .sin_addr.s_addr = htonl(INADDR_ANY),
889 .sin_port = htons(port),
890 };
891 const char *netid;
892 int error;
893
894 switch (protocol) {
895 case IPPROTO_UDP:
896 netid = RPCBIND_NETID_UDP;
897 break;
898 case IPPROTO_TCP:
899 netid = RPCBIND_NETID_TCP;
900 break;
901 default:
902 return -ENOPROTOOPT;
903 }
904
905 error = rpcb_v4_register(net, program, version,
906 (const struct sockaddr *)&sin, netid);
907
908 /*
909 * User space didn't support rpcbind v4, so retry this
910 * registration request with the legacy rpcbind v2 protocol.
911 */
912 if (error == -EPROTONOSUPPORT)
913 error = rpcb_register(net, program, version, protocol, port);
914
915 return error;
916}
917
918#if IS_ENABLED(CONFIG_IPV6)
919/*
920 * Register an "inet6" protocol family netid with the local
921 * rpcbind daemon via an rpcbind v4 SET request.
922 *
923 * No netconfig infrastructure is available in the kernel, so
924 * we map IP_ protocol numbers to netids by hand.
925 *
926 * Returns zero on success; a negative errno value is returned
927 * if any error occurs.
928 */
929static int __svc_rpcb_register6(struct net *net, const u32 program,
930 const u32 version,
931 const unsigned short protocol,
932 const unsigned short port)
933{
934 const struct sockaddr_in6 sin6 = {
935 .sin6_family = AF_INET6,
936 .sin6_addr = IN6ADDR_ANY_INIT,
937 .sin6_port = htons(port),
938 };
939 const char *netid;
940 int error;
941
942 switch (protocol) {
943 case IPPROTO_UDP:
944 netid = RPCBIND_NETID_UDP6;
945 break;
946 case IPPROTO_TCP:
947 netid = RPCBIND_NETID_TCP6;
948 break;
949 default:
950 return -ENOPROTOOPT;
951 }
952
953 error = rpcb_v4_register(net, program, version,
954 (const struct sockaddr *)&sin6, netid);
955
956 /*
957 * User space didn't support rpcbind version 4, so we won't
958 * use a PF_INET6 listener.
959 */
960 if (error == -EPROTONOSUPPORT)
961 error = -EAFNOSUPPORT;
962
963 return error;
964}
965#endif /* IS_ENABLED(CONFIG_IPV6) */
966
967/*
968 * Register a kernel RPC service via rpcbind version 4.
969 *
970 * Returns zero on success; a negative errno value is returned
971 * if any error occurs.
972 */
973static int __svc_register(struct net *net, const char *progname,
974 const u32 program, const u32 version,
975 const int family,
976 const unsigned short protocol,
977 const unsigned short port)
978{
979 int error = -EAFNOSUPPORT;
980
981 switch (family) {
982 case PF_INET:
983 error = __svc_rpcb_register4(net, program, version,
984 protocol, port);
985 break;
986#if IS_ENABLED(CONFIG_IPV6)
987 case PF_INET6:
988 error = __svc_rpcb_register6(net, program, version,
989 protocol, port);
990#endif
991 }
992
993 return error;
994}
995
996/**
997 * svc_register - register an RPC service with the local portmapper
998 * @serv: svc_serv struct for the service to register
999 * @net: net namespace for the service to register
1000 * @family: protocol family of service's listener socket
1001 * @proto: transport protocol number to advertise
1002 * @port: port to advertise
1003 *
1004 * Service is registered for any address in the passed-in protocol family
1005 */
1006int svc_register(const struct svc_serv *serv, struct net *net,
1007 const int family, const unsigned short proto,
1008 const unsigned short port)
1009{
1010 struct svc_program *progp;
1011 const struct svc_version *vers;
1012 unsigned int i;
1013 int error = 0;
1014
1015 WARN_ON_ONCE(proto == 0 && port == 0);
1016 if (proto == 0 && port == 0)
1017 return -EINVAL;
1018
1019 for (progp = serv->sv_program; progp; progp = progp->pg_next) {
1020 for (i = 0; i < progp->pg_nvers; i++) {
1021 vers = progp->pg_vers[i];
1022 if (vers == NULL)
1023 continue;
1024
1025 dprintk("svc: svc_register(%sv%d, %s, %u, %u)%s\n",
1026 progp->pg_name,
1027 i,
1028 proto == IPPROTO_UDP? "udp" : "tcp",
1029 port,
1030 family,
1031 vers->vs_hidden ?
1032 " (but not telling portmap)" : "");
1033
1034 if (vers->vs_hidden)
1035 continue;
1036
1037 /*
1038 * Don't register a UDP port if we need congestion
1039 * control.
1040 */
1041 if (vers->vs_need_cong_ctrl && proto == IPPROTO_UDP)
1042 continue;
1043
1044 error = __svc_register(net, progp->pg_name, progp->pg_prog,
1045 i, family, proto, port);
1046
1047 if (vers->vs_rpcb_optnl) {
1048 error = 0;
1049 continue;
1050 }
1051
1052 if (error < 0) {
1053 printk(KERN_WARNING "svc: failed to register "
1054 "%sv%u RPC service (errno %d).\n",
1055 progp->pg_name, i, -error);
1056 break;
1057 }
1058 }
1059 }
1060
1061 return error;
1062}
1063
1064/*
1065 * If user space is running rpcbind, it should take the v4 UNSET
1066 * and clear everything for this [program, version]. If user space
1067 * is running portmap, it will reject the v4 UNSET, but won't have
1068 * any "inet6" entries anyway. So a PMAP_UNSET should be sufficient
1069 * in this case to clear all existing entries for [program, version].
1070 */
1071static void __svc_unregister(struct net *net, const u32 program, const u32 version,
1072 const char *progname)
1073{
1074 int error;
1075
1076 error = rpcb_v4_register(net, program, version, NULL, "");
1077
1078 /*
1079 * User space didn't support rpcbind v4, so retry this
1080 * request with the legacy rpcbind v2 protocol.
1081 */
1082 if (error == -EPROTONOSUPPORT)
1083 error = rpcb_register(net, program, version, 0, 0);
1084
1085 dprintk("svc: %s(%sv%u), error %d\n",
1086 __func__, progname, version, error);
1087}
1088
1089/*
1090 * All netids, bind addresses and ports registered for [program, version]
1091 * are removed from the local rpcbind database (if the service is not
1092 * hidden) to make way for a new instance of the service.
1093 *
1094 * The result of unregistration is reported via dprintk for those who want
1095 * verification of the result, but is otherwise not important.
1096 */
1097static void svc_unregister(const struct svc_serv *serv, struct net *net)
1098{
1099 struct svc_program *progp;
1100 unsigned long flags;
1101 unsigned int i;
1102
1103 clear_thread_flag(TIF_SIGPENDING);
1104
1105 for (progp = serv->sv_program; progp; progp = progp->pg_next) {
1106 for (i = 0; i < progp->pg_nvers; i++) {
1107 if (progp->pg_vers[i] == NULL)
1108 continue;
1109 if (progp->pg_vers[i]->vs_hidden)
1110 continue;
1111
1112 dprintk("svc: attempting to unregister %sv%u\n",
1113 progp->pg_name, i);
1114 __svc_unregister(net, progp->pg_prog, i, progp->pg_name);
1115 }
1116 }
1117
1118 spin_lock_irqsave(¤t->sighand->siglock, flags);
1119 recalc_sigpending();
1120 spin_unlock_irqrestore(¤t->sighand->siglock, flags);
1121}
1122
1123/*
1124 * dprintk the given error with the address of the client that caused it.
1125 */
1126#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
1127static __printf(2, 3)
1128void svc_printk(struct svc_rqst *rqstp, const char *fmt, ...)
1129{
1130 struct va_format vaf;
1131 va_list args;
1132 char buf[RPC_MAX_ADDRBUFLEN];
1133
1134 va_start(args, fmt);
1135
1136 vaf.fmt = fmt;
1137 vaf.va = &args;
1138
1139 dprintk("svc: %s: %pV", svc_print_addr(rqstp, buf, sizeof(buf)), &vaf);
1140
1141 va_end(args);
1142}
1143#else
1144static __printf(2,3) void svc_printk(struct svc_rqst *rqstp, const char *fmt, ...) {}
1145#endif
1146
1147/*
1148 * Common routine for processing the RPC request.
1149 */
1150static int
1151svc_process_common(struct svc_rqst *rqstp, struct kvec *argv, struct kvec *resv)
1152{
1153 struct svc_program *progp;
1154 const struct svc_version *versp = NULL; /* compiler food */
1155 const struct svc_procedure *procp = NULL;
1156 struct svc_serv *serv = rqstp->rq_server;
1157 __be32 *statp;
1158 u32 prog, vers, proc;
1159 __be32 auth_stat, rpc_stat;
1160 int auth_res;
1161 __be32 *reply_statp;
1162
1163 rpc_stat = rpc_success;
1164
1165 if (argv->iov_len < 6*4)
1166 goto err_short_len;
1167
1168 /* Will be turned off by GSS integrity and privacy services */
1169 set_bit(RQ_SPLICE_OK, &rqstp->rq_flags);
1170 /* Will be turned off only when NFSv4 Sessions are used */
1171 set_bit(RQ_USEDEFERRAL, &rqstp->rq_flags);
1172 clear_bit(RQ_DROPME, &rqstp->rq_flags);
1173
1174 /* Setup reply header */
1175 rqstp->rq_xprt->xpt_ops->xpo_prep_reply_hdr(rqstp);
1176
1177 svc_putu32(resv, rqstp->rq_xid);
1178
1179 vers = svc_getnl(argv);
1180
1181 /* First words of reply: */
1182 svc_putnl(resv, 1); /* REPLY */
1183
1184 if (vers != 2) /* RPC version number */
1185 goto err_bad_rpc;
1186
1187 /* Save position in case we later decide to reject: */
1188 reply_statp = resv->iov_base + resv->iov_len;
1189
1190 svc_putnl(resv, 0); /* ACCEPT */
1191
1192 rqstp->rq_prog = prog = svc_getnl(argv); /* program number */
1193 rqstp->rq_vers = vers = svc_getnl(argv); /* version number */
1194 rqstp->rq_proc = proc = svc_getnl(argv); /* procedure number */
1195
1196 for (progp = serv->sv_program; progp; progp = progp->pg_next)
1197 if (prog == progp->pg_prog)
1198 break;
1199
1200 /*
1201 * Decode auth data, and add verifier to reply buffer.
1202 * We do this before anything else in order to get a decent
1203 * auth verifier.
1204 */
1205 auth_res = svc_authenticate(rqstp, &auth_stat);
1206 /* Also give the program a chance to reject this call: */
1207 if (auth_res == SVC_OK && progp) {
1208 auth_stat = rpc_autherr_badcred;
1209 auth_res = progp->pg_authenticate(rqstp);
1210 }
1211 switch (auth_res) {
1212 case SVC_OK:
1213 break;
1214 case SVC_GARBAGE:
1215 goto err_garbage;
1216 case SVC_SYSERR:
1217 rpc_stat = rpc_system_err;
1218 goto err_bad;
1219 case SVC_DENIED:
1220 goto err_bad_auth;
1221 case SVC_CLOSE:
1222 goto close;
1223 case SVC_DROP:
1224 goto dropit;
1225 case SVC_COMPLETE:
1226 goto sendit;
1227 }
1228
1229 if (progp == NULL)
1230 goto err_bad_prog;
1231
1232 if (vers >= progp->pg_nvers ||
1233 !(versp = progp->pg_vers[vers]))
1234 goto err_bad_vers;
1235
1236 /*
1237 * Some protocol versions (namely NFSv4) require some form of
1238 * congestion control. (See RFC 7530 section 3.1 paragraph 2)
1239 * In other words, UDP is not allowed. We mark those when setting
1240 * up the svc_xprt, and verify that here.
1241 *
1242 * The spec is not very clear about what error should be returned
1243 * when someone tries to access a server that is listening on UDP
1244 * for lower versions. RPC_PROG_MISMATCH seems to be the closest
1245 * fit.
1246 */
1247 if (versp->vs_need_cong_ctrl &&
1248 !test_bit(XPT_CONG_CTRL, &rqstp->rq_xprt->xpt_flags))
1249 goto err_bad_vers;
1250
1251 procp = versp->vs_proc + proc;
1252 if (proc >= versp->vs_nproc || !procp->pc_func)
1253 goto err_bad_proc;
1254 rqstp->rq_procinfo = procp;
1255
1256 /* Syntactic check complete */
1257 serv->sv_stats->rpccnt++;
1258 trace_svc_process(rqstp, progp->pg_name);
1259
1260 /* Build the reply header. */
1261 statp = resv->iov_base +resv->iov_len;
1262 svc_putnl(resv, RPC_SUCCESS);
1263
1264 /* Bump per-procedure stats counter */
1265 versp->vs_count[proc]++;
1266
1267 /* Initialize storage for argp and resp */
1268 memset(rqstp->rq_argp, 0, procp->pc_argsize);
1269 memset(rqstp->rq_resp, 0, procp->pc_ressize);
1270
1271 /* un-reserve some of the out-queue now that we have a
1272 * better idea of reply size
1273 */
1274 if (procp->pc_xdrressize)
1275 svc_reserve_auth(rqstp, procp->pc_xdrressize<<2);
1276
1277 /* Call the function that processes the request. */
1278 if (!versp->vs_dispatch) {
1279 /*
1280 * Decode arguments
1281 * XXX: why do we ignore the return value?
1282 */
1283 if (procp->pc_decode &&
1284 !procp->pc_decode(rqstp, argv->iov_base))
1285 goto err_garbage;
1286
1287 *statp = procp->pc_func(rqstp);
1288
1289 /* Encode reply */
1290 if (*statp == rpc_drop_reply ||
1291 test_bit(RQ_DROPME, &rqstp->rq_flags)) {
1292 if (procp->pc_release)
1293 procp->pc_release(rqstp);
1294 goto dropit;
1295 }
1296 if (*statp == rpc_autherr_badcred) {
1297 if (procp->pc_release)
1298 procp->pc_release(rqstp);
1299 goto err_bad_auth;
1300 }
1301 if (*statp == rpc_success && procp->pc_encode &&
1302 !procp->pc_encode(rqstp, resv->iov_base + resv->iov_len)) {
1303 dprintk("svc: failed to encode reply\n");
1304 /* serv->sv_stats->rpcsystemerr++; */
1305 *statp = rpc_system_err;
1306 }
1307 } else {
1308 dprintk("svc: calling dispatcher\n");
1309 if (!versp->vs_dispatch(rqstp, statp)) {
1310 /* Release reply info */
1311 if (procp->pc_release)
1312 procp->pc_release(rqstp);
1313 goto dropit;
1314 }
1315 }
1316
1317 /* Check RPC status result */
1318 if (*statp != rpc_success)
1319 resv->iov_len = ((void*)statp) - resv->iov_base + 4;
1320
1321 /* Release reply info */
1322 if (procp->pc_release)
1323 procp->pc_release(rqstp);
1324
1325 if (procp->pc_encode == NULL)
1326 goto dropit;
1327
1328 sendit:
1329 if (svc_authorise(rqstp))
1330 goto close;
1331 return 1; /* Caller can now send it */
1332
1333 dropit:
1334 svc_authorise(rqstp); /* doesn't hurt to call this twice */
1335 dprintk("svc: svc_process dropit\n");
1336 return 0;
1337
1338 close:
1339 if (test_bit(XPT_TEMP, &rqstp->rq_xprt->xpt_flags))
1340 svc_close_xprt(rqstp->rq_xprt);
1341 dprintk("svc: svc_process close\n");
1342 return 0;
1343
1344err_short_len:
1345 svc_printk(rqstp, "short len %zd, dropping request\n",
1346 argv->iov_len);
1347 goto close;
1348
1349err_bad_rpc:
1350 serv->sv_stats->rpcbadfmt++;
1351 svc_putnl(resv, 1); /* REJECT */
1352 svc_putnl(resv, 0); /* RPC_MISMATCH */
1353 svc_putnl(resv, 2); /* Only RPCv2 supported */
1354 svc_putnl(resv, 2);
1355 goto sendit;
1356
1357err_bad_auth:
1358 dprintk("svc: authentication failed (%d)\n", ntohl(auth_stat));
1359 serv->sv_stats->rpcbadauth++;
1360 /* Restore write pointer to location of accept status: */
1361 xdr_ressize_check(rqstp, reply_statp);
1362 svc_putnl(resv, 1); /* REJECT */
1363 svc_putnl(resv, 1); /* AUTH_ERROR */
1364 svc_putnl(resv, ntohl(auth_stat)); /* status */
1365 goto sendit;
1366
1367err_bad_prog:
1368 dprintk("svc: unknown program %d\n", prog);
1369 serv->sv_stats->rpcbadfmt++;
1370 svc_putnl(resv, RPC_PROG_UNAVAIL);
1371 goto sendit;
1372
1373err_bad_vers:
1374 svc_printk(rqstp, "unknown version (%d for prog %d, %s)\n",
1375 vers, prog, progp->pg_name);
1376
1377 serv->sv_stats->rpcbadfmt++;
1378 svc_putnl(resv, RPC_PROG_MISMATCH);
1379 svc_putnl(resv, progp->pg_lovers);
1380 svc_putnl(resv, progp->pg_hivers);
1381 goto sendit;
1382
1383err_bad_proc:
1384 svc_printk(rqstp, "unknown procedure (%d)\n", proc);
1385
1386 serv->sv_stats->rpcbadfmt++;
1387 svc_putnl(resv, RPC_PROC_UNAVAIL);
1388 goto sendit;
1389
1390err_garbage:
1391 svc_printk(rqstp, "failed to decode args\n");
1392
1393 rpc_stat = rpc_garbage_args;
1394err_bad:
1395 serv->sv_stats->rpcbadfmt++;
1396 svc_putnl(resv, ntohl(rpc_stat));
1397 goto sendit;
1398}
1399
1400/*
1401 * Process the RPC request.
1402 */
1403int
1404svc_process(struct svc_rqst *rqstp)
1405{
1406 struct kvec *argv = &rqstp->rq_arg.head[0];
1407 struct kvec *resv = &rqstp->rq_res.head[0];
1408 struct svc_serv *serv = rqstp->rq_server;
1409 u32 dir;
1410
1411 /*
1412 * Setup response xdr_buf.
1413 * Initially it has just one page
1414 */
1415 rqstp->rq_next_page = &rqstp->rq_respages[1];
1416 resv->iov_base = page_address(rqstp->rq_respages[0]);
1417 resv->iov_len = 0;
1418 rqstp->rq_res.pages = rqstp->rq_respages + 1;
1419 rqstp->rq_res.len = 0;
1420 rqstp->rq_res.page_base = 0;
1421 rqstp->rq_res.page_len = 0;
1422 rqstp->rq_res.buflen = PAGE_SIZE;
1423 rqstp->rq_res.tail[0].iov_base = NULL;
1424 rqstp->rq_res.tail[0].iov_len = 0;
1425
1426 dir = svc_getnl(argv);
1427 if (dir != 0) {
1428 /* direction != CALL */
1429 svc_printk(rqstp, "bad direction %d, dropping request\n", dir);
1430 serv->sv_stats->rpcbadfmt++;
1431 goto out_drop;
1432 }
1433
1434 /* Returns 1 for send, 0 for drop */
1435 if (likely(svc_process_common(rqstp, argv, resv)))
1436 return svc_send(rqstp);
1437
1438out_drop:
1439 svc_drop(rqstp);
1440 return 0;
1441}
1442EXPORT_SYMBOL_GPL(svc_process);
1443
1444#if defined(CONFIG_SUNRPC_BACKCHANNEL)
1445/*
1446 * Process a backchannel RPC request that arrived over an existing
1447 * outbound connection
1448 */
1449int
1450bc_svc_process(struct svc_serv *serv, struct rpc_rqst *req,
1451 struct svc_rqst *rqstp)
1452{
1453 struct kvec *argv = &rqstp->rq_arg.head[0];
1454 struct kvec *resv = &rqstp->rq_res.head[0];
1455 struct rpc_task *task;
1456 int proc_error;
1457 int error;
1458
1459 dprintk("svc: %s(%p)\n", __func__, req);
1460
1461 /* Build the svc_rqst used by the common processing routine */
1462 rqstp->rq_xprt = serv->sv_bc_xprt;
1463 rqstp->rq_xid = req->rq_xid;
1464 rqstp->rq_prot = req->rq_xprt->prot;
1465 rqstp->rq_server = serv;
1466
1467 rqstp->rq_addrlen = sizeof(req->rq_xprt->addr);
1468 memcpy(&rqstp->rq_addr, &req->rq_xprt->addr, rqstp->rq_addrlen);
1469 memcpy(&rqstp->rq_arg, &req->rq_rcv_buf, sizeof(rqstp->rq_arg));
1470 memcpy(&rqstp->rq_res, &req->rq_snd_buf, sizeof(rqstp->rq_res));
1471
1472 /* Adjust the argument buffer length */
1473 rqstp->rq_arg.len = req->rq_private_buf.len;
1474 if (rqstp->rq_arg.len <= rqstp->rq_arg.head[0].iov_len) {
1475 rqstp->rq_arg.head[0].iov_len = rqstp->rq_arg.len;
1476 rqstp->rq_arg.page_len = 0;
1477 } else if (rqstp->rq_arg.len <= rqstp->rq_arg.head[0].iov_len +
1478 rqstp->rq_arg.page_len)
1479 rqstp->rq_arg.page_len = rqstp->rq_arg.len -
1480 rqstp->rq_arg.head[0].iov_len;
1481 else
1482 rqstp->rq_arg.len = rqstp->rq_arg.head[0].iov_len +
1483 rqstp->rq_arg.page_len;
1484
1485 /* reset result send buffer "put" position */
1486 resv->iov_len = 0;
1487
1488 /*
1489 * Skip the next two words because they've already been
1490 * processed in the transport
1491 */
1492 svc_getu32(argv); /* XID */
1493 svc_getnl(argv); /* CALLDIR */
1494
1495 /* Parse and execute the bc call */
1496 proc_error = svc_process_common(rqstp, argv, resv);
1497
1498 atomic_inc(&req->rq_xprt->bc_free_slots);
1499 if (!proc_error) {
1500 /* Processing error: drop the request */
1501 xprt_free_bc_request(req);
1502 return 0;
1503 }
1504
1505 /* Finally, send the reply synchronously */
1506 memcpy(&req->rq_snd_buf, &rqstp->rq_res, sizeof(req->rq_snd_buf));
1507 task = rpc_run_bc_task(req);
1508 if (IS_ERR(task)) {
1509 error = PTR_ERR(task);
1510 goto out;
1511 }
1512
1513 WARN_ON_ONCE(atomic_read(&task->tk_count) != 1);
1514 error = task->tk_status;
1515 rpc_put_task(task);
1516
1517out:
1518 dprintk("svc: %s(), error=%d\n", __func__, error);
1519 return error;
1520}
1521EXPORT_SYMBOL_GPL(bc_svc_process);
1522#endif /* CONFIG_SUNRPC_BACKCHANNEL */
1523
1524/*
1525 * Return (transport-specific) limit on the rpc payload.
1526 */
1527u32 svc_max_payload(const struct svc_rqst *rqstp)
1528{
1529 u32 max = rqstp->rq_xprt->xpt_class->xcl_max_payload;
1530
1531 if (rqstp->rq_server->sv_max_payload < max)
1532 max = rqstp->rq_server->sv_max_payload;
1533 return max;
1534}
1535EXPORT_SYMBOL_GPL(svc_max_payload);
1536
1537/**
1538 * svc_fill_write_vector - Construct data argument for VFS write call
1539 * @rqstp: svc_rqst to operate on
1540 * @first: buffer containing first section of write payload
1541 * @total: total number of bytes of write payload
1542 *
1543 * Returns the number of elements populated in the data argument array.
1544 */
1545unsigned int svc_fill_write_vector(struct svc_rqst *rqstp, struct kvec *first,
1546 size_t total)
1547{
1548 struct kvec *vec = rqstp->rq_vec;
1549 struct page **pages;
1550 unsigned int i;
1551
1552 /* Some types of transport can present the write payload
1553 * entirely in rq_arg.pages. In this case, @first is empty.
1554 */
1555 i = 0;
1556 if (first->iov_len) {
1557 vec[i].iov_base = first->iov_base;
1558 vec[i].iov_len = min_t(size_t, total, first->iov_len);
1559 total -= vec[i].iov_len;
1560 ++i;
1561 }
1562
1563 WARN_ON_ONCE(rqstp->rq_arg.page_base != 0);
1564 pages = rqstp->rq_arg.pages;
1565 while (total) {
1566 vec[i].iov_base = page_address(*pages);
1567 vec[i].iov_len = min_t(size_t, total, PAGE_SIZE);
1568 total -= vec[i].iov_len;
1569 ++i;
1570
1571 ++pages;
1572 }
1573
1574 WARN_ON_ONCE(i > ARRAY_SIZE(rqstp->rq_vec));
1575 return i;
1576}
1577EXPORT_SYMBOL_GPL(svc_fill_write_vector);
1578
1579/**
1580 * svc_fill_symlink_pathname - Construct pathname argument for VFS symlink call
1581 * @rqstp: svc_rqst to operate on
1582 * @first: buffer containing first section of pathname
1583 * @total: total length of the pathname argument
1584 *
1585 * Returns pointer to a NUL-terminated string, or an ERR_PTR. The buffer is
1586 * released automatically when @rqstp is recycled.
1587 */
1588char *svc_fill_symlink_pathname(struct svc_rqst *rqstp, struct kvec *first,
1589 size_t total)
1590{
1591 struct xdr_buf *arg = &rqstp->rq_arg;
1592 struct page **pages;
1593 char *result;
1594
1595 /* VFS API demands a NUL-terminated pathname. This function
1596 * uses a page from @rqstp as the pathname buffer, to enable
1597 * direct placement. Thus the total buffer size is PAGE_SIZE.
1598 * Space in this buffer for NUL-termination requires that we
1599 * cap the size of the returned symlink pathname just a
1600 * little early.
1601 */
1602 if (total > PAGE_SIZE - 1)
1603 return ERR_PTR(-ENAMETOOLONG);
1604
1605 /* Some types of transport can present the pathname entirely
1606 * in rq_arg.pages. If not, then copy the pathname into one
1607 * page.
1608 */
1609 pages = arg->pages;
1610 WARN_ON_ONCE(arg->page_base != 0);
1611 if (first->iov_base == 0) {
1612 result = page_address(*pages);
1613 result[total] = '\0';
1614 } else {
1615 size_t len, remaining;
1616 char *dst;
1617
1618 result = page_address(*(rqstp->rq_next_page++));
1619 dst = result;
1620 remaining = total;
1621
1622 len = min_t(size_t, total, first->iov_len);
1623 memcpy(dst, first->iov_base, len);
1624 dst += len;
1625 remaining -= len;
1626
1627 /* No more than one page left */
1628 if (remaining) {
1629 len = min_t(size_t, remaining, PAGE_SIZE);
1630 memcpy(dst, page_address(*pages), len);
1631 dst += len;
1632 }
1633
1634 *dst = '\0';
1635 }
1636
1637 /* Sanity check: we don't allow the pathname argument to
1638 * contain a NUL byte.
1639 */
1640 if (strlen(result) != total)
1641 return ERR_PTR(-EINVAL);
1642 return result;
1643}
1644EXPORT_SYMBOL_GPL(svc_fill_symlink_pathname);