1 | /* SPDX-License-Identifier: GPL-2.0 */ |
2 | /* |
3 | * linux/include/linux/sunrpc/svc.h |
4 | * |
5 | * RPC server declarations. |
6 | * |
7 | * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de> |
8 | */ |
9 | |
10 | |
11 | #ifndef SUNRPC_SVC_H |
12 | #define SUNRPC_SVC_H |
13 | |
14 | #include <linux/in.h> |
15 | #include <linux/in6.h> |
16 | #include <linux/sunrpc/types.h> |
17 | #include <linux/sunrpc/xdr.h> |
18 | #include <linux/sunrpc/auth.h> |
19 | #include <linux/sunrpc/svcauth.h> |
20 | #include <linux/lwq.h> |
21 | #include <linux/wait.h> |
22 | #include <linux/mm.h> |
23 | #include <linux/pagevec.h> |
24 | |
25 | /* |
26 | * |
27 | * RPC service thread pool. |
28 | * |
29 | * Pool of threads and temporary sockets. Generally there is only |
30 | * a single one of these per RPC service, but on NUMA machines those |
31 | * services that can benefit from it (i.e. nfs but not lockd) will |
32 | * have one pool per NUMA node. This optimisation reduces cross- |
33 | * node traffic on multi-node NUMA NFS servers. |
34 | */ |
35 | struct svc_pool { |
36 | unsigned int sp_id; /* pool id; also node id on NUMA */ |
37 | struct lwq sp_xprts; /* pending transports */ |
38 | atomic_t sp_nrthreads; /* # of threads in pool */ |
39 | struct list_head sp_all_threads; /* all server threads */ |
40 | struct llist_head sp_idle_threads; /* idle server threads */ |
41 | |
42 | /* statistics on pool operation */ |
43 | struct percpu_counter sp_messages_arrived; |
44 | struct percpu_counter sp_sockets_queued; |
45 | struct percpu_counter sp_threads_woken; |
46 | |
47 | unsigned long sp_flags; |
48 | } ____cacheline_aligned_in_smp; |
49 | |
50 | /* bits for sp_flags */ |
51 | enum { |
52 | SP_TASK_PENDING, /* still work to do even if no xprt is queued */ |
53 | SP_NEED_VICTIM, /* One thread needs to agree to exit */ |
54 | SP_VICTIM_REMAINS, /* One thread needs to actually exit */ |
55 | }; |
56 | |
57 | |
58 | /* |
59 | * RPC service. |
60 | * |
61 | * An RPC service is a ``daemon,'' possibly multithreaded, which |
62 | * receives and processes incoming RPC messages. |
63 | * It has one or more transport sockets associated with it, and maintains |
64 | * a list of idle threads waiting for input. |
65 | * |
66 | * We currently do not support more than one RPC program per daemon. |
67 | */ |
68 | struct svc_serv { |
69 | struct svc_program * sv_program; /* RPC program */ |
70 | struct svc_stat * sv_stats; /* RPC statistics */ |
71 | spinlock_t sv_lock; |
72 | struct kref sv_refcnt; |
73 | unsigned int sv_nrthreads; /* # of server threads */ |
74 | unsigned int sv_maxconn; /* max connections allowed or |
75 | * '0' causing max to be based |
76 | * on number of threads. */ |
77 | |
78 | unsigned int sv_max_payload; /* datagram payload size */ |
79 | unsigned int sv_max_mesg; /* max_payload + 1 page for overheads */ |
80 | unsigned int sv_xdrsize; /* XDR buffer size */ |
81 | struct list_head sv_permsocks; /* all permanent sockets */ |
82 | struct list_head sv_tempsocks; /* all temporary sockets */ |
83 | int sv_tmpcnt; /* count of temporary sockets */ |
84 | struct timer_list sv_temptimer; /* timer for aging temporary sockets */ |
85 | |
86 | char * sv_name; /* service name */ |
87 | |
88 | unsigned int sv_nrpools; /* number of thread pools */ |
89 | struct svc_pool * sv_pools; /* array of thread pools */ |
90 | int (*sv_threadfn)(void *data); |
91 | |
92 | #if defined(CONFIG_SUNRPC_BACKCHANNEL) |
93 | struct lwq sv_cb_list; /* queue for callback requests |
94 | * that arrive over the same |
95 | * connection */ |
96 | bool sv_bc_enabled; /* service uses backchannel */ |
97 | #endif /* CONFIG_SUNRPC_BACKCHANNEL */ |
98 | }; |
99 | |
100 | /** |
101 | * svc_get() - increment reference count on a SUNRPC serv |
102 | * @serv: the svc_serv to have count incremented |
103 | * |
104 | * Returns: the svc_serv that was passed in. |
105 | */ |
106 | static inline struct svc_serv *svc_get(struct svc_serv *serv) |
107 | { |
108 | kref_get(kref: &serv->sv_refcnt); |
109 | return serv; |
110 | } |
111 | |
112 | void svc_destroy(struct kref *); |
113 | |
114 | /** |
115 | * svc_put - decrement reference count on a SUNRPC serv |
116 | * @serv: the svc_serv to have count decremented |
117 | * |
118 | * When the reference count reaches zero, svc_destroy() |
119 | * is called to clean up and free the serv. |
120 | */ |
121 | static inline void svc_put(struct svc_serv *serv) |
122 | { |
123 | kref_put(kref: &serv->sv_refcnt, release: svc_destroy); |
124 | } |
125 | |
126 | /* |
127 | * Maximum payload size supported by a kernel RPC server. |
128 | * This is use to determine the max number of pages nfsd is |
129 | * willing to return in a single READ operation. |
130 | * |
131 | * These happen to all be powers of 2, which is not strictly |
132 | * necessary but helps enforce the real limitation, which is |
133 | * that they should be multiples of PAGE_SIZE. |
134 | * |
135 | * For UDP transports, a block plus NFS,RPC, and UDP headers |
136 | * has to fit into the IP datagram limit of 64K. The largest |
137 | * feasible number for all known page sizes is probably 48K, |
138 | * but we choose 32K here. This is the same as the historical |
139 | * Linux limit; someone who cares more about NFS/UDP performance |
140 | * can test a larger number. |
141 | * |
142 | * For TCP transports we have more freedom. A size of 1MB is |
143 | * chosen to match the client limit. Other OSes are known to |
144 | * have larger limits, but those numbers are probably beyond |
145 | * the point of diminishing returns. |
146 | */ |
147 | #define RPCSVC_MAXPAYLOAD (1*1024*1024u) |
148 | #define RPCSVC_MAXPAYLOAD_TCP RPCSVC_MAXPAYLOAD |
149 | #define RPCSVC_MAXPAYLOAD_UDP (32*1024u) |
150 | |
151 | extern u32 svc_max_payload(const struct svc_rqst *rqstp); |
152 | |
153 | /* |
154 | * RPC Requests and replies are stored in one or more pages. |
155 | * We maintain an array of pages for each server thread. |
156 | * Requests are copied into these pages as they arrive. Remaining |
157 | * pages are available to write the reply into. |
158 | * |
159 | * Pages are sent using ->sendmsg with MSG_SPLICE_PAGES so each server thread |
160 | * needs to allocate more to replace those used in sending. To help keep track |
161 | * of these pages we have a receive list where all pages initialy live, and a |
162 | * send list where pages are moved to when there are to be part of a reply. |
163 | * |
164 | * We use xdr_buf for holding responses as it fits well with NFS |
165 | * read responses (that have a header, and some data pages, and possibly |
166 | * a tail) and means we can share some client side routines. |
167 | * |
168 | * The xdr_buf.head kvec always points to the first page in the rq_*pages |
169 | * list. The xdr_buf.pages pointer points to the second page on that |
170 | * list. xdr_buf.tail points to the end of the first page. |
171 | * This assumes that the non-page part of an rpc reply will fit |
172 | * in a page - NFSd ensures this. lockd also has no trouble. |
173 | * |
174 | * Each request/reply pair can have at most one "payload", plus two pages, |
175 | * one for the request, and one for the reply. |
176 | * We using ->sendfile to return read data, we might need one extra page |
177 | * if the request is not page-aligned. So add another '1'. |
178 | */ |
179 | #define RPCSVC_MAXPAGES ((RPCSVC_MAXPAYLOAD+PAGE_SIZE-1)/PAGE_SIZE \ |
180 | + 2 + 1) |
181 | |
182 | /* |
183 | * The context of a single thread, including the request currently being |
184 | * processed. |
185 | */ |
186 | struct svc_rqst { |
187 | struct list_head rq_all; /* all threads list */ |
188 | struct llist_node rq_idle; /* On the idle list */ |
189 | struct rcu_head rq_rcu_head; /* for RCU deferred kfree */ |
190 | struct svc_xprt * rq_xprt; /* transport ptr */ |
191 | |
192 | struct sockaddr_storage rq_addr; /* peer address */ |
193 | size_t rq_addrlen; |
194 | struct sockaddr_storage rq_daddr; /* dest addr of request |
195 | * - reply from here */ |
196 | size_t rq_daddrlen; |
197 | |
198 | struct svc_serv * rq_server; /* RPC service definition */ |
199 | struct svc_pool * rq_pool; /* thread pool */ |
200 | const struct svc_procedure *rq_procinfo;/* procedure info */ |
201 | struct auth_ops * rq_authop; /* authentication flavour */ |
202 | struct svc_cred rq_cred; /* auth info */ |
203 | void * rq_xprt_ctxt; /* transport specific context ptr */ |
204 | struct svc_deferred_req*rq_deferred; /* deferred request we are replaying */ |
205 | |
206 | struct xdr_buf rq_arg; |
207 | struct xdr_stream rq_arg_stream; |
208 | struct xdr_stream rq_res_stream; |
209 | struct page *rq_scratch_page; |
210 | struct xdr_buf rq_res; |
211 | struct page *rq_pages[RPCSVC_MAXPAGES + 1]; |
212 | struct page * *rq_respages; /* points into rq_pages */ |
213 | struct page * *rq_next_page; /* next reply page to use */ |
214 | struct page * *rq_page_end; /* one past the last page */ |
215 | |
216 | struct folio_batch rq_fbatch; |
217 | struct kvec rq_vec[RPCSVC_MAXPAGES]; /* generally useful.. */ |
218 | struct bio_vec rq_bvec[RPCSVC_MAXPAGES]; |
219 | |
220 | __be32 rq_xid; /* transmission id */ |
221 | u32 rq_prog; /* program number */ |
222 | u32 rq_vers; /* program version */ |
223 | u32 rq_proc; /* procedure number */ |
224 | u32 rq_prot; /* IP protocol */ |
225 | int rq_cachetype; /* catering to nfsd */ |
226 | unsigned long rq_flags; /* flags field */ |
227 | ktime_t rq_qtime; /* enqueue time */ |
228 | |
229 | void * rq_argp; /* decoded arguments */ |
230 | void * rq_resp; /* xdr'd results */ |
231 | __be32 *rq_accept_statp; |
232 | void * rq_auth_data; /* flavor-specific data */ |
233 | __be32 rq_auth_stat; /* authentication status */ |
234 | int rq_auth_slack; /* extra space xdr code |
235 | * should leave in head |
236 | * for krb5i, krb5p. |
237 | */ |
238 | int rq_reserved; /* space on socket outq |
239 | * reserved for this request |
240 | */ |
241 | ktime_t rq_stime; /* start time */ |
242 | |
243 | struct cache_req rq_chandle; /* handle passed to caches for |
244 | * request delaying |
245 | */ |
246 | /* Catering to nfsd */ |
247 | struct auth_domain * rq_client; /* RPC peer info */ |
248 | struct auth_domain * rq_gssclient; /* "gss/"-style peer info */ |
249 | struct task_struct *rq_task; /* service thread */ |
250 | struct net *rq_bc_net; /* pointer to backchannel's |
251 | * net namespace |
252 | */ |
253 | void ** rq_lease_breaker; /* The v4 client breaking a lease */ |
254 | unsigned int rq_status_counter; /* RPC processing counter */ |
255 | }; |
256 | |
257 | /* bits for rq_flags */ |
258 | enum { |
259 | RQ_SECURE, /* secure port */ |
260 | RQ_LOCAL, /* local request */ |
261 | RQ_USEDEFERRAL, /* use deferral */ |
262 | RQ_DROPME, /* drop current reply */ |
263 | RQ_SPLICE_OK, /* turned off in gss privacy to prevent |
264 | * encrypting page cache pages */ |
265 | RQ_VICTIM, /* Have agreed to shut down */ |
266 | RQ_DATA, /* request has data */ |
267 | }; |
268 | |
269 | #define SVC_NET(rqst) (rqst->rq_xprt ? rqst->rq_xprt->xpt_net : rqst->rq_bc_net) |
270 | |
271 | /* |
272 | * Rigorous type checking on sockaddr type conversions |
273 | */ |
274 | static inline struct sockaddr_in *svc_addr_in(const struct svc_rqst *rqst) |
275 | { |
276 | return (struct sockaddr_in *) &rqst->rq_addr; |
277 | } |
278 | |
279 | static inline struct sockaddr_in6 *svc_addr_in6(const struct svc_rqst *rqst) |
280 | { |
281 | return (struct sockaddr_in6 *) &rqst->rq_addr; |
282 | } |
283 | |
284 | static inline struct sockaddr *svc_addr(const struct svc_rqst *rqst) |
285 | { |
286 | return (struct sockaddr *) &rqst->rq_addr; |
287 | } |
288 | |
289 | static inline struct sockaddr_in *svc_daddr_in(const struct svc_rqst *rqst) |
290 | { |
291 | return (struct sockaddr_in *) &rqst->rq_daddr; |
292 | } |
293 | |
294 | static inline struct sockaddr_in6 *svc_daddr_in6(const struct svc_rqst *rqst) |
295 | { |
296 | return (struct sockaddr_in6 *) &rqst->rq_daddr; |
297 | } |
298 | |
299 | static inline struct sockaddr *svc_daddr(const struct svc_rqst *rqst) |
300 | { |
301 | return (struct sockaddr *) &rqst->rq_daddr; |
302 | } |
303 | |
304 | /** |
305 | * svc_thread_should_stop - check if this thread should stop |
306 | * @rqstp: the thread that might need to stop |
307 | * |
308 | * To stop an svc thread, the pool flags SP_NEED_VICTIM and SP_VICTIM_REMAINS |
309 | * are set. The first thread which sees SP_NEED_VICTIM clears it, becoming |
310 | * the victim using this function. It should then promptly call |
311 | * svc_exit_thread() to complete the process, clearing SP_VICTIM_REMAINS |
312 | * so the task waiting for a thread to exit can wake and continue. |
313 | * |
314 | * Return values: |
315 | * %true: caller should invoke svc_exit_thread() |
316 | * %false: caller should do nothing |
317 | */ |
318 | static inline bool svc_thread_should_stop(struct svc_rqst *rqstp) |
319 | { |
320 | if (test_and_clear_bit(nr: SP_NEED_VICTIM, addr: &rqstp->rq_pool->sp_flags)) |
321 | set_bit(nr: RQ_VICTIM, addr: &rqstp->rq_flags); |
322 | |
323 | return test_bit(RQ_VICTIM, &rqstp->rq_flags); |
324 | } |
325 | |
326 | struct svc_deferred_req { |
327 | u32 prot; /* protocol (UDP or TCP) */ |
328 | struct svc_xprt *xprt; |
329 | struct sockaddr_storage addr; /* where reply must go */ |
330 | size_t addrlen; |
331 | struct sockaddr_storage daddr; /* where reply must come from */ |
332 | size_t daddrlen; |
333 | void *xprt_ctxt; |
334 | struct cache_deferred_req handle; |
335 | int argslen; |
336 | __be32 args[]; |
337 | }; |
338 | |
339 | struct svc_process_info { |
340 | union { |
341 | int (*dispatch)(struct svc_rqst *rqstp); |
342 | struct { |
343 | unsigned int lovers; |
344 | unsigned int hivers; |
345 | } mismatch; |
346 | }; |
347 | }; |
348 | |
349 | /* |
350 | * List of RPC programs on the same transport endpoint |
351 | */ |
352 | struct svc_program { |
353 | struct svc_program * pg_next; /* other programs (same xprt) */ |
354 | u32 pg_prog; /* program number */ |
355 | unsigned int pg_lovers; /* lowest version */ |
356 | unsigned int pg_hivers; /* highest version */ |
357 | unsigned int pg_nvers; /* number of versions */ |
358 | const struct svc_version **pg_vers; /* version array */ |
359 | char * pg_name; /* service name */ |
360 | char * pg_class; /* class name: services sharing authentication */ |
361 | struct svc_stat * pg_stats; /* rpc statistics */ |
362 | enum svc_auth_status (*pg_authenticate)(struct svc_rqst *rqstp); |
363 | __be32 (*pg_init_request)(struct svc_rqst *, |
364 | const struct svc_program *, |
365 | struct svc_process_info *); |
366 | int (*pg_rpcbind_set)(struct net *net, |
367 | const struct svc_program *, |
368 | u32 version, int family, |
369 | unsigned short proto, |
370 | unsigned short port); |
371 | }; |
372 | |
373 | /* |
374 | * RPC program version |
375 | */ |
376 | struct svc_version { |
377 | u32 vs_vers; /* version number */ |
378 | u32 vs_nproc; /* number of procedures */ |
379 | const struct svc_procedure *vs_proc; /* per-procedure info */ |
380 | unsigned long __percpu *vs_count; /* call counts */ |
381 | u32 vs_xdrsize; /* xdrsize needed for this version */ |
382 | |
383 | /* Don't register with rpcbind */ |
384 | bool vs_hidden; |
385 | |
386 | /* Don't care if the rpcbind registration fails */ |
387 | bool vs_rpcb_optnl; |
388 | |
389 | /* Need xprt with congestion control */ |
390 | bool vs_need_cong_ctrl; |
391 | |
392 | /* Dispatch function */ |
393 | int (*vs_dispatch)(struct svc_rqst *rqstp); |
394 | }; |
395 | |
396 | /* |
397 | * RPC procedure info |
398 | */ |
399 | struct svc_procedure { |
400 | /* process the request: */ |
401 | __be32 (*pc_func)(struct svc_rqst *); |
402 | /* XDR decode args: */ |
403 | bool (*pc_decode)(struct svc_rqst *rqstp, |
404 | struct xdr_stream *xdr); |
405 | /* XDR encode result: */ |
406 | bool (*pc_encode)(struct svc_rqst *rqstp, |
407 | struct xdr_stream *xdr); |
408 | /* XDR free result: */ |
409 | void (*pc_release)(struct svc_rqst *); |
410 | unsigned int pc_argsize; /* argument struct size */ |
411 | unsigned int pc_argzero; /* how much of argument to clear */ |
412 | unsigned int pc_ressize; /* result struct size */ |
413 | unsigned int pc_cachetype; /* cache info (NFS) */ |
414 | unsigned int pc_xdrressize; /* maximum size of XDR reply */ |
415 | const char * pc_name; /* for display */ |
416 | }; |
417 | |
418 | /* |
419 | * Function prototypes. |
420 | */ |
421 | int svc_rpcb_setup(struct svc_serv *serv, struct net *net); |
422 | void svc_rpcb_cleanup(struct svc_serv *serv, struct net *net); |
423 | int svc_bind(struct svc_serv *serv, struct net *net); |
424 | struct svc_serv *svc_create(struct svc_program *, unsigned int, |
425 | int (*threadfn)(void *data)); |
426 | struct svc_rqst *svc_rqst_alloc(struct svc_serv *serv, |
427 | struct svc_pool *pool, int node); |
428 | bool svc_rqst_replace_page(struct svc_rqst *rqstp, |
429 | struct page *page); |
430 | void svc_rqst_release_pages(struct svc_rqst *rqstp); |
431 | void svc_rqst_free(struct svc_rqst *); |
432 | void svc_exit_thread(struct svc_rqst *); |
433 | struct svc_serv * svc_create_pooled(struct svc_program *, unsigned int, |
434 | int (*threadfn)(void *data)); |
435 | int svc_set_num_threads(struct svc_serv *, struct svc_pool *, int); |
436 | int svc_pool_stats_open(struct svc_serv *serv, struct file *file); |
437 | void svc_process(struct svc_rqst *rqstp); |
438 | void svc_process_bc(struct rpc_rqst *req, struct svc_rqst *rqstp); |
439 | int svc_register(const struct svc_serv *, struct net *, const int, |
440 | const unsigned short, const unsigned short); |
441 | |
442 | void svc_wake_up(struct svc_serv *); |
443 | void svc_reserve(struct svc_rqst *rqstp, int space); |
444 | void svc_pool_wake_idle_thread(struct svc_pool *pool); |
445 | struct svc_pool *svc_pool_for_cpu(struct svc_serv *serv); |
446 | char * svc_print_addr(struct svc_rqst *, char *, size_t); |
447 | const char * svc_proc_name(const struct svc_rqst *rqstp); |
448 | int svc_encode_result_payload(struct svc_rqst *rqstp, |
449 | unsigned int offset, |
450 | unsigned int length); |
451 | unsigned int svc_fill_write_vector(struct svc_rqst *rqstp, |
452 | struct xdr_buf *payload); |
453 | char *svc_fill_symlink_pathname(struct svc_rqst *rqstp, |
454 | struct kvec *first, void *p, |
455 | size_t total); |
456 | __be32 svc_generic_init_request(struct svc_rqst *rqstp, |
457 | const struct svc_program *progp, |
458 | struct svc_process_info *procinfo); |
459 | int svc_generic_rpcbind_set(struct net *net, |
460 | const struct svc_program *progp, |
461 | u32 version, int family, |
462 | unsigned short proto, |
463 | unsigned short port); |
464 | int svc_rpcbind_set_version(struct net *net, |
465 | const struct svc_program *progp, |
466 | u32 version, int family, |
467 | unsigned short proto, |
468 | unsigned short port); |
469 | |
470 | #define RPC_MAX_ADDRBUFLEN (63U) |
471 | |
472 | /* |
473 | * When we want to reduce the size of the reserved space in the response |
474 | * buffer, we need to take into account the size of any checksum data that |
475 | * may be at the end of the packet. This is difficult to determine exactly |
476 | * for all cases without actually generating the checksum, so we just use a |
477 | * static value. |
478 | */ |
479 | static inline void svc_reserve_auth(struct svc_rqst *rqstp, int space) |
480 | { |
481 | svc_reserve(rqstp, space: space + rqstp->rq_auth_slack); |
482 | } |
483 | |
484 | /** |
485 | * svcxdr_init_decode - Prepare an xdr_stream for Call decoding |
486 | * @rqstp: controlling server RPC transaction context |
487 | * |
488 | */ |
489 | static inline void svcxdr_init_decode(struct svc_rqst *rqstp) |
490 | { |
491 | struct xdr_stream *xdr = &rqstp->rq_arg_stream; |
492 | struct xdr_buf *buf = &rqstp->rq_arg; |
493 | struct kvec *argv = buf->head; |
494 | |
495 | WARN_ON(buf->len != buf->head->iov_len + buf->page_len + buf->tail->iov_len); |
496 | buf->len = buf->head->iov_len + buf->page_len + buf->tail->iov_len; |
497 | |
498 | xdr_init_decode(xdr, buf, p: argv->iov_base, NULL); |
499 | xdr_set_scratch_page(xdr, page: rqstp->rq_scratch_page); |
500 | } |
501 | |
502 | /** |
503 | * svcxdr_init_encode - Prepare an xdr_stream for svc Reply encoding |
504 | * @rqstp: controlling server RPC transaction context |
505 | * |
506 | */ |
507 | static inline void svcxdr_init_encode(struct svc_rqst *rqstp) |
508 | { |
509 | struct xdr_stream *xdr = &rqstp->rq_res_stream; |
510 | struct xdr_buf *buf = &rqstp->rq_res; |
511 | struct kvec *resv = buf->head; |
512 | |
513 | xdr_reset_scratch_buffer(xdr); |
514 | |
515 | xdr->buf = buf; |
516 | xdr->iov = resv; |
517 | xdr->p = resv->iov_base + resv->iov_len; |
518 | xdr->end = resv->iov_base + PAGE_SIZE; |
519 | buf->len = resv->iov_len; |
520 | xdr->page_ptr = buf->pages - 1; |
521 | buf->buflen = PAGE_SIZE * (rqstp->rq_page_end - buf->pages); |
522 | xdr->rqst = NULL; |
523 | } |
524 | |
525 | /** |
526 | * svcxdr_encode_opaque_pages - Insert pages into an xdr_stream |
527 | * @xdr: xdr_stream to be updated |
528 | * @pages: array of pages to insert |
529 | * @base: starting offset of first data byte in @pages |
530 | * @len: number of data bytes in @pages to insert |
531 | * |
532 | * After the @pages are added, the tail iovec is instantiated pointing |
533 | * to end of the head buffer, and the stream is set up to encode |
534 | * subsequent items into the tail. |
535 | */ |
536 | static inline void svcxdr_encode_opaque_pages(struct svc_rqst *rqstp, |
537 | struct xdr_stream *xdr, |
538 | struct page **pages, |
539 | unsigned int base, |
540 | unsigned int len) |
541 | { |
542 | xdr_write_pages(xdr, pages, base, len); |
543 | xdr->page_ptr = rqstp->rq_next_page - 1; |
544 | } |
545 | |
546 | /** |
547 | * svcxdr_set_auth_slack - |
548 | * @rqstp: RPC transaction |
549 | * @slack: buffer space to reserve for the transaction's security flavor |
550 | * |
551 | * Set the request's slack space requirement, and set aside that much |
552 | * space in the rqstp's rq_res.head for use when the auth wraps the Reply. |
553 | */ |
554 | static inline void svcxdr_set_auth_slack(struct svc_rqst *rqstp, int slack) |
555 | { |
556 | struct xdr_stream *xdr = &rqstp->rq_res_stream; |
557 | struct xdr_buf *buf = &rqstp->rq_res; |
558 | struct kvec *resv = buf->head; |
559 | |
560 | rqstp->rq_auth_slack = slack; |
561 | |
562 | xdr->end -= XDR_QUADLEN(slack); |
563 | buf->buflen -= rqstp->rq_auth_slack; |
564 | |
565 | WARN_ON(xdr->iov != resv); |
566 | WARN_ON(xdr->p > xdr->end); |
567 | } |
568 | |
569 | /** |
570 | * svcxdr_set_accept_stat - Reserve space for the accept_stat field |
571 | * @rqstp: RPC transaction context |
572 | * |
573 | * Return values: |
574 | * %true: Success |
575 | * %false: No response buffer space was available |
576 | */ |
577 | static inline bool svcxdr_set_accept_stat(struct svc_rqst *rqstp) |
578 | { |
579 | struct xdr_stream *xdr = &rqstp->rq_res_stream; |
580 | |
581 | rqstp->rq_accept_statp = xdr_reserve_space(xdr, XDR_UNIT); |
582 | if (unlikely(!rqstp->rq_accept_statp)) |
583 | return false; |
584 | *rqstp->rq_accept_statp = rpc_success; |
585 | return true; |
586 | } |
587 | |
588 | #endif /* SUNRPC_SVC_H */ |
589 | |