2 * linux/include/linux/sunrpc/svc.h
4 * RPC server declarations.
6 * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
14 #include <linux/in6.h>
15 #include <linux/sunrpc/types.h>
16 #include <linux/sunrpc/xdr.h>
17 #include <linux/sunrpc/auth.h>
18 #include <linux/sunrpc/svcauth.h>
19 #include <linux/wait.h>
23 * This is the RPC server thread function prototype
25 typedef int (*svc_thread_fn)(void *);
27 /* statistics for svc_pool structures */
28 struct svc_pool_stats {
29 atomic_long_t packets;
30 unsigned long sockets_queued;
31 atomic_long_t threads_woken;
32 atomic_long_t threads_timedout;
37 * RPC service thread pool.
39 * Pool of threads and temporary sockets. Generally there is only
40 * a single one of these per RPC service, but on NUMA machines those
41 * services that can benefit from it (i.e. nfs but not lockd) will
42 * have one pool per NUMA node. This optimisation reduces cross-
43 * node traffic on multi-node NUMA NFS servers.
46 unsigned int sp_id; /* pool id; also node id on NUMA */
47 spinlock_t sp_lock; /* protects all fields */
48 struct list_head sp_sockets; /* pending sockets */
49 unsigned int sp_nrthreads; /* # of threads in pool */
50 struct list_head sp_all_threads; /* all server threads */
51 struct svc_pool_stats sp_stats; /* statistics on pool operation */
52 #define SP_TASK_PENDING (0) /* still work to do even if no
54 unsigned long sp_flags;
55 } ____cacheline_aligned_in_smp;
60 * An RPC service is a ``daemon,'' possibly multithreaded, which
61 * receives and processes incoming RPC messages.
62 * It has one or more transport sockets associated with it, and maintains
63 * a list of idle threads waiting for input.
65 * We currently do not support more than one RPC program per daemon.
68 struct svc_program * sv_program; /* RPC program */
69 struct svc_stat * sv_stats; /* RPC statistics */
71 unsigned int sv_nrthreads; /* # of server threads */
72 unsigned int sv_maxconn; /* max connections allowed or
73 * '0' causing max to be based
74 * on number of threads. */
76 unsigned int sv_max_payload; /* datagram payload size */
77 unsigned int sv_max_mesg; /* max_payload + 1 page for overheads */
78 unsigned int sv_xdrsize; /* XDR buffer size */
79 struct list_head sv_permsocks; /* all permanent sockets */
80 struct list_head sv_tempsocks; /* all temporary sockets */
81 int sv_tmpcnt; /* count of temporary sockets */
82 struct timer_list sv_temptimer; /* timer for aging temporary sockets */
84 char * sv_name; /* service name */
86 unsigned int sv_nrpools; /* number of thread pools */
87 struct svc_pool * sv_pools; /* array of thread pools */
89 void (*sv_shutdown)(struct svc_serv *serv,
91 /* Callback to use when last thread
95 struct module * sv_module; /* optional module to count when
97 svc_thread_fn sv_function; /* main function for threads */
98 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
99 struct list_head sv_cb_list; /* queue for callback requests
100 * that arrive over the same
102 spinlock_t sv_cb_lock; /* protects the svc_cb_list */
103 wait_queue_head_t sv_cb_waitq; /* sleep here if there are no
104 * entries in the svc_cb_list */
105 struct svc_xprt *sv_bc_xprt; /* callback on fore channel */
106 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
110 * We use sv_nrthreads as a reference count. svc_destroy() drops
111 * this refcount, so we need to bump it up around operations that
112 * change the number of threads. Horrible, but there it is.
113 * Should be called with the "service mutex" held.
115 static inline void svc_get(struct svc_serv *serv)
117 serv->sv_nrthreads++;
121 * Maximum payload size supported by a kernel RPC server.
122 * This is use to determine the max number of pages nfsd is
123 * willing to return in a single READ operation.
125 * These happen to all be powers of 2, which is not strictly
126 * necessary but helps enforce the real limitation, which is
127 * that they should be multiples of PAGE_CACHE_SIZE.
129 * For UDP transports, a block plus NFS,RPC, and UDP headers
130 * has to fit into the IP datagram limit of 64K. The largest
131 * feasible number for all known page sizes is probably 48K,
132 * but we choose 32K here. This is the same as the historical
133 * Linux limit; someone who cares more about NFS/UDP performance
134 * can test a larger number.
136 * For TCP transports we have more freedom. A size of 1MB is
137 * chosen to match the client limit. Other OSes are known to
138 * have larger limits, but those numbers are probably beyond
139 * the point of diminishing returns.
141 #define RPCSVC_MAXPAYLOAD (1*1024*1024u)
142 #define RPCSVC_MAXPAYLOAD_TCP RPCSVC_MAXPAYLOAD
143 #define RPCSVC_MAXPAYLOAD_UDP (32*1024u)
145 extern u32 svc_max_payload(const struct svc_rqst *rqstp);
148 * RPC Requsts and replies are stored in one or more pages.
149 * We maintain an array of pages for each server thread.
150 * Requests are copied into these pages as they arrive. Remaining
151 * pages are available to write the reply into.
153 * Pages are sent using ->sendpage so each server thread needs to
154 * allocate more to replace those used in sending. To help keep track
155 * of these pages we have a receive list where all pages initialy live,
156 * and a send list where pages are moved to when there are to be part
159 * We use xdr_buf for holding responses as it fits well with NFS
160 * read responses (that have a header, and some data pages, and possibly
161 * a tail) and means we can share some client side routines.
163 * The xdr_buf.head kvec always points to the first page in the rq_*pages
164 * list. The xdr_buf.pages pointer points to the second page on that
165 * list. xdr_buf.tail points to the end of the first page.
166 * This assumes that the non-page part of an rpc reply will fit
167 * in a page - NFSd ensures this. lockd also has no trouble.
169 * Each request/reply pair can have at most one "payload", plus two pages,
170 * one for the request, and one for the reply.
171 * We using ->sendfile to return read data, we might need one extra page
172 * if the request is not page-aligned. So add another '1'.
174 #define RPCSVC_MAXPAGES ((RPCSVC_MAXPAYLOAD+PAGE_SIZE-1)/PAGE_SIZE \
177 static inline u32 svc_getnl(struct kvec *iov)
182 iov->iov_base = (void*)vp;
183 iov->iov_len -= sizeof(__be32);
187 static inline void svc_putnl(struct kvec *iov, u32 val)
189 __be32 *vp = iov->iov_base + iov->iov_len;
191 iov->iov_len += sizeof(__be32);
194 static inline __be32 svc_getu32(struct kvec *iov)
199 iov->iov_base = (void*)vp;
200 iov->iov_len -= sizeof(__be32);
204 static inline void svc_ungetu32(struct kvec *iov)
206 __be32 *vp = (__be32 *)iov->iov_base;
207 iov->iov_base = (void *)(vp - 1);
208 iov->iov_len += sizeof(*vp);
211 static inline void svc_putu32(struct kvec *iov, __be32 val)
213 __be32 *vp = iov->iov_base + iov->iov_len;
215 iov->iov_len += sizeof(__be32);
219 * The context of a single thread, including the request currently being
223 struct list_head rq_all; /* all threads list */
224 struct rcu_head rq_rcu_head; /* for RCU deferred kfree */
225 struct svc_xprt * rq_xprt; /* transport ptr */
227 struct sockaddr_storage rq_addr; /* peer address */
229 struct sockaddr_storage rq_daddr; /* dest addr of request
230 * - reply from here */
233 struct svc_serv * rq_server; /* RPC service definition */
234 struct svc_pool * rq_pool; /* thread pool */
235 struct svc_procedure * rq_procinfo; /* procedure info */
236 struct auth_ops * rq_authop; /* authentication flavour */
237 struct svc_cred rq_cred; /* auth info */
238 void * rq_xprt_ctxt; /* transport specific context ptr */
239 struct svc_deferred_req*rq_deferred; /* deferred request we are replaying */
241 size_t rq_xprt_hlen; /* xprt header len */
242 struct xdr_buf rq_arg;
243 struct xdr_buf rq_res;
244 struct page * rq_pages[RPCSVC_MAXPAGES];
245 struct page * *rq_respages; /* points into rq_pages */
246 struct page * *rq_next_page; /* next reply page to use */
247 struct page * *rq_page_end; /* one past the last page */
249 struct kvec rq_vec[RPCSVC_MAXPAGES]; /* generally useful.. */
251 __be32 rq_xid; /* transmission id */
252 u32 rq_prog; /* program number */
253 u32 rq_vers; /* program version */
254 u32 rq_proc; /* procedure number */
255 u32 rq_prot; /* IP protocol */
256 int rq_cachetype; /* catering to nfsd */
257 #define RQ_SECURE (0) /* secure port */
258 #define RQ_LOCAL (1) /* local request */
259 #define RQ_USEDEFERRAL (2) /* use deferral */
260 #define RQ_DROPME (3) /* drop current reply */
261 #define RQ_SPLICE_OK (4) /* turned off in gss privacy
262 * to prevent encrypting page
264 #define RQ_VICTIM (5) /* about to be shut down */
265 #define RQ_BUSY (6) /* request is busy */
266 unsigned long rq_flags; /* flags field */
268 void * rq_argp; /* decoded arguments */
269 void * rq_resp; /* xdr'd results */
270 void * rq_auth_data; /* flavor-specific data */
271 int rq_auth_slack; /* extra space xdr code
272 * should leave in head
275 int rq_reserved; /* space on socket outq
276 * reserved for this request
279 struct cache_req rq_chandle; /* handle passed to caches for
282 /* Catering to nfsd */
283 struct auth_domain * rq_client; /* RPC peer info */
284 struct auth_domain * rq_gssclient; /* "gss/"-style peer info */
285 struct svc_cacherep * rq_cacherep; /* cache info */
286 struct task_struct *rq_task; /* service thread */
287 spinlock_t rq_lock; /* per-request lock */
290 #define SVC_NET(svc_rqst) (svc_rqst->rq_xprt->xpt_net)
293 * Rigorous type checking on sockaddr type conversions
295 static inline struct sockaddr_in *svc_addr_in(const struct svc_rqst *rqst)
297 return (struct sockaddr_in *) &rqst->rq_addr;
300 static inline struct sockaddr_in6 *svc_addr_in6(const struct svc_rqst *rqst)
302 return (struct sockaddr_in6 *) &rqst->rq_addr;
305 static inline struct sockaddr *svc_addr(const struct svc_rqst *rqst)
307 return (struct sockaddr *) &rqst->rq_addr;
310 static inline struct sockaddr_in *svc_daddr_in(const struct svc_rqst *rqst)
312 return (struct sockaddr_in *) &rqst->rq_daddr;
315 static inline struct sockaddr_in6 *svc_daddr_in6(const struct svc_rqst *rqst)
317 return (struct sockaddr_in6 *) &rqst->rq_daddr;
320 static inline struct sockaddr *svc_daddr(const struct svc_rqst *rqst)
322 return (struct sockaddr *) &rqst->rq_daddr;
326 * Check buffer bounds after decoding arguments
329 xdr_argsize_check(struct svc_rqst *rqstp, __be32 *p)
331 char *cp = (char *)p;
332 struct kvec *vec = &rqstp->rq_arg.head[0];
333 return cp >= (char*)vec->iov_base
334 && cp <= (char*)vec->iov_base + vec->iov_len;
338 xdr_ressize_check(struct svc_rqst *rqstp, __be32 *p)
340 struct kvec *vec = &rqstp->rq_res.head[0];
343 vec->iov_len = cp - (char*)vec->iov_base;
345 return vec->iov_len <= PAGE_SIZE;
348 static inline void svc_free_res_pages(struct svc_rqst *rqstp)
350 while (rqstp->rq_next_page != rqstp->rq_respages) {
351 struct page **pp = --rqstp->rq_next_page;
359 struct svc_deferred_req {
360 u32 prot; /* protocol (UDP or TCP) */
361 struct svc_xprt *xprt;
362 struct sockaddr_storage addr; /* where reply must go */
364 struct sockaddr_storage daddr; /* where reply must come from */
366 struct cache_deferred_req handle;
373 * List of RPC programs on the same transport endpoint
376 struct svc_program * pg_next; /* other programs (same xprt) */
377 u32 pg_prog; /* program number */
378 unsigned int pg_lovers; /* lowest version */
379 unsigned int pg_hivers; /* highest version */
380 unsigned int pg_nvers; /* number of versions */
381 struct svc_version ** pg_vers; /* version array */
382 char * pg_name; /* service name */
383 char * pg_class; /* class name: services sharing authentication */
384 struct svc_stat * pg_stats; /* rpc statistics */
385 int (*pg_authenticate)(struct svc_rqst *);
389 * RPC program version
392 u32 vs_vers; /* version number */
393 u32 vs_nproc; /* number of procedures */
394 struct svc_procedure * vs_proc; /* per-procedure info */
395 u32 vs_xdrsize; /* xdrsize needed for this version */
397 unsigned int vs_hidden : 1, /* Don't register with portmapper.
398 * Only used for nfsacl so far. */
399 vs_rpcb_optnl:1;/* Don't care the result of register.
400 * Only used for nfsv4. */
402 /* Override dispatch function (e.g. when caching replies).
403 * A return value of 0 means drop the request.
404 * vs_dispatch == NULL means use default dispatcher.
406 int (*vs_dispatch)(struct svc_rqst *, __be32 *);
412 typedef __be32 (*svc_procfunc)(struct svc_rqst *, void *argp, void *resp);
413 struct svc_procedure {
414 svc_procfunc pc_func; /* process the request */
415 kxdrproc_t pc_decode; /* XDR decode args */
416 kxdrproc_t pc_encode; /* XDR encode result */
417 kxdrproc_t pc_release; /* XDR free result */
418 unsigned int pc_argsize; /* argument struct size */
419 unsigned int pc_ressize; /* result struct size */
420 unsigned int pc_count; /* call count */
421 unsigned int pc_cachetype; /* cache info (NFS) */
422 unsigned int pc_xdrressize; /* maximum size of XDR reply */
426 * Function prototypes.
428 int svc_rpcb_setup(struct svc_serv *serv, struct net *net);
429 void svc_rpcb_cleanup(struct svc_serv *serv, struct net *net);
430 int svc_bind(struct svc_serv *serv, struct net *net);
431 struct svc_serv *svc_create(struct svc_program *, unsigned int,
432 void (*shutdown)(struct svc_serv *, struct net *net));
433 struct svc_rqst *svc_prepare_thread(struct svc_serv *serv,
434 struct svc_pool *pool, int node);
435 void svc_exit_thread(struct svc_rqst *);
436 struct svc_serv * svc_create_pooled(struct svc_program *, unsigned int,
437 void (*shutdown)(struct svc_serv *, struct net *net),
438 svc_thread_fn, struct module *);
439 int svc_set_num_threads(struct svc_serv *, struct svc_pool *, int);
440 int svc_pool_stats_open(struct svc_serv *serv, struct file *file);
441 void svc_destroy(struct svc_serv *);
442 void svc_shutdown_net(struct svc_serv *, struct net *);
443 int svc_process(struct svc_rqst *);
444 int bc_svc_process(struct svc_serv *, struct rpc_rqst *,
446 int svc_register(const struct svc_serv *, struct net *, const int,
447 const unsigned short, const unsigned short);
449 void svc_wake_up(struct svc_serv *);
450 void svc_reserve(struct svc_rqst *rqstp, int space);
451 struct svc_pool * svc_pool_for_cpu(struct svc_serv *serv, int cpu);
452 char * svc_print_addr(struct svc_rqst *, char *, size_t);
454 #define RPC_MAX_ADDRBUFLEN (63U)
457 * When we want to reduce the size of the reserved space in the response
458 * buffer, we need to take into account the size of any checksum data that
459 * may be at the end of the packet. This is difficult to determine exactly
460 * for all cases without actually generating the checksum, so we just use a
463 static inline void svc_reserve_auth(struct svc_rqst *rqstp, int space)
465 svc_reserve(rqstp, space + rqstp->rq_auth_slack);
468 #endif /* SUNRPC_SVC_H */