1 /* 2 * linux/include/linux/sunrpc/svc.h 3 * 4 * RPC server declarations. 5 * 6 * Copyright (C) 1995, 1996 Olaf Kirch <[email protected]> 7 */ 8 9 10 #ifndef SUNRPC_SVC_H 11 #define SUNRPC_SVC_H 12 13 #include <linux/in.h> 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> 20 #include <linux/mm.h> 21 22 /* 23 * This is the RPC server thread function prototype 24 */ 25 typedef int (*svc_thread_fn)(void *); 26 27 /* statistics for svc_pool structures */ 28 struct svc_pool_stats { 29 unsigned long packets; 30 unsigned long sockets_queued; 31 unsigned long threads_woken; 32 unsigned long overloads_avoided; 33 unsigned long threads_timedout; 34 }; 35 36 /* 37 * 38 * RPC service thread pool. 39 * 40 * Pool of threads and temporary sockets. Generally there is only 41 * a single one of these per RPC service, but on NUMA machines those 42 * services that can benefit from it (i.e. nfs but not lockd) will 43 * have one pool per NUMA node. This optimisation reduces cross- 44 * node traffic on multi-node NUMA NFS servers. 45 */ 46 struct svc_pool { 47 unsigned int sp_id; /* pool id; also node id on NUMA */ 48 spinlock_t sp_lock; /* protects all fields */ 49 struct list_head sp_threads; /* idle server threads */ 50 struct list_head sp_sockets; /* pending sockets */ 51 unsigned int sp_nrthreads; /* # of threads in pool */ 52 struct list_head sp_all_threads; /* all server threads */ 53 int sp_nwaking; /* number of threads woken but not yet active */ 54 struct svc_pool_stats sp_stats; /* statistics on pool operation */ 55 } ____cacheline_aligned_in_smp; 56 57 /* 58 * RPC service. 59 * 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. 64 * 65 * We currently do not support more than one RPC program per daemon. 66 */ 67 struct svc_serv { 68 struct svc_program * sv_program; /* RPC program */ 69 struct svc_stat * sv_stats; /* RPC statistics */ 70 spinlock_t sv_lock; 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. */ 75 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 */ 83 84 char * sv_name; /* service name */ 85 86 unsigned int sv_nrpools; /* number of thread pools */ 87 struct svc_pool * sv_pools; /* array of thread pools */ 88 89 void (*sv_shutdown)(struct svc_serv *serv); 90 /* Callback to use when last thread 91 * exits. 92 */ 93 94 struct module * sv_module; /* optional module to count when 95 * adding threads */ 96 svc_thread_fn sv_function; /* main function for threads */ 97 unsigned int sv_drc_max_pages; /* Total pages for DRC */ 98 unsigned int sv_drc_pages_used;/* DRC pages used */ 99 #if defined(CONFIG_NFS_V4_1) 100 struct list_head sv_cb_list; /* queue for callback requests 101 * that arrive over the same 102 * connection */ 103 spinlock_t sv_cb_lock; /* protects the svc_cb_list */ 104 wait_queue_head_t sv_cb_waitq; /* sleep here if there are no 105 * entries in the svc_cb_list */ 106 struct svc_xprt *bc_xprt; 107 #endif /* CONFIG_NFS_V4_1 */ 108 }; 109 110 /* 111 * We use sv_nrthreads as a reference count. svc_destroy() drops 112 * this refcount, so we need to bump it up around operations that 113 * change the number of threads. Horrible, but there it is. 114 * Should be called with the BKL held. 115 */ 116 static inline void svc_get(struct svc_serv *serv) 117 { 118 serv->sv_nrthreads++; 119 } 120 121 /* 122 * Maximum payload size supported by a kernel RPC server. 123 * This is use to determine the max number of pages nfsd is 124 * willing to return in a single READ operation. 125 * 126 * These happen to all be powers of 2, which is not strictly 127 * necessary but helps enforce the real limitation, which is 128 * that they should be multiples of PAGE_CACHE_SIZE. 129 * 130 * For UDP transports, a block plus NFS,RPC, and UDP headers 131 * has to fit into the IP datagram limit of 64K. The largest 132 * feasible number for all known page sizes is probably 48K, 133 * but we choose 32K here. This is the same as the historical 134 * Linux limit; someone who cares more about NFS/UDP performance 135 * can test a larger number. 136 * 137 * For TCP transports we have more freedom. A size of 1MB is 138 * chosen to match the client limit. Other OSes are known to 139 * have larger limits, but those numbers are probably beyond 140 * the point of diminishing returns. 141 */ 142 #define RPCSVC_MAXPAYLOAD (1*1024*1024u) 143 #define RPCSVC_MAXPAYLOAD_TCP RPCSVC_MAXPAYLOAD 144 #define RPCSVC_MAXPAYLOAD_UDP (32*1024u) 145 146 extern u32 svc_max_payload(const struct svc_rqst *rqstp); 147 148 /* 149 * RPC Requsts and replies are stored in one or more pages. 150 * We maintain an array of pages for each server thread. 151 * Requests are copied into these pages as they arrive. Remaining 152 * pages are available to write the reply into. 153 * 154 * Pages are sent using ->sendpage so each server thread needs to 155 * allocate more to replace those used in sending. To help keep track 156 * of these pages we have a receive list where all pages initialy live, 157 * and a send list where pages are moved to when there are to be part 158 * of a reply. 159 * 160 * We use xdr_buf for holding responses as it fits well with NFS 161 * read responses (that have a header, and some data pages, and possibly 162 * a tail) and means we can share some client side routines. 163 * 164 * The xdr_buf.head kvec always points to the first page in the rq_*pages 165 * list. The xdr_buf.pages pointer points to the second page on that 166 * list. xdr_buf.tail points to the end of the first page. 167 * This assumes that the non-page part of an rpc reply will fit 168 * in a page - NFSd ensures this. lockd also has no trouble. 169 * 170 * Each request/reply pair can have at most one "payload", plus two pages, 171 * one for the request, and one for the reply. 172 * We using ->sendfile to return read data, we might need one extra page 173 * if the request is not page-aligned. So add another '1'. 174 */ 175 #define RPCSVC_MAXPAGES ((RPCSVC_MAXPAYLOAD+PAGE_SIZE-1)/PAGE_SIZE \ 176 + 2 + 1) 177 178 static inline u32 svc_getnl(struct kvec *iov) 179 { 180 __be32 val, *vp; 181 vp = iov->iov_base; 182 val = *vp++; 183 iov->iov_base = (void*)vp; 184 iov->iov_len -= sizeof(__be32); 185 return ntohl(val); 186 } 187 188 static inline void svc_putnl(struct kvec *iov, u32 val) 189 { 190 __be32 *vp = iov->iov_base + iov->iov_len; 191 *vp = htonl(val); 192 iov->iov_len += sizeof(__be32); 193 } 194 195 static inline __be32 svc_getu32(struct kvec *iov) 196 { 197 __be32 val, *vp; 198 vp = iov->iov_base; 199 val = *vp++; 200 iov->iov_base = (void*)vp; 201 iov->iov_len -= sizeof(__be32); 202 return val; 203 } 204 205 static inline void svc_ungetu32(struct kvec *iov) 206 { 207 __be32 *vp = (__be32 *)iov->iov_base; 208 iov->iov_base = (void *)(vp - 1); 209 iov->iov_len += sizeof(*vp); 210 } 211 212 static inline void svc_putu32(struct kvec *iov, __be32 val) 213 { 214 __be32 *vp = iov->iov_base + iov->iov_len; 215 *vp = val; 216 iov->iov_len += sizeof(__be32); 217 } 218 219 union svc_addr_u { 220 struct in_addr addr; 221 struct in6_addr addr6; 222 }; 223 224 /* 225 * The context of a single thread, including the request currently being 226 * processed. 227 */ 228 struct svc_rqst { 229 struct list_head rq_list; /* idle list */ 230 struct list_head rq_all; /* all threads list */ 231 struct svc_xprt * rq_xprt; /* transport ptr */ 232 struct sockaddr_storage rq_addr; /* peer address */ 233 size_t rq_addrlen; 234 235 struct svc_serv * rq_server; /* RPC service definition */ 236 struct svc_pool * rq_pool; /* thread pool */ 237 struct svc_procedure * rq_procinfo; /* procedure info */ 238 struct auth_ops * rq_authop; /* authentication flavour */ 239 u32 rq_flavor; /* pseudoflavor */ 240 struct svc_cred rq_cred; /* auth info */ 241 void * rq_xprt_ctxt; /* transport specific context ptr */ 242 struct svc_deferred_req*rq_deferred; /* deferred request we are replaying */ 243 int rq_usedeferral; /* use deferral */ 244 245 size_t rq_xprt_hlen; /* xprt header len */ 246 struct xdr_buf rq_arg; 247 struct xdr_buf rq_res; 248 struct page * rq_pages[RPCSVC_MAXPAGES]; 249 struct page * *rq_respages; /* points into rq_pages */ 250 int rq_resused; /* number of pages used for result */ 251 252 struct kvec rq_vec[RPCSVC_MAXPAGES]; /* generally useful.. */ 253 254 __be32 rq_xid; /* transmission id */ 255 u32 rq_prog; /* program number */ 256 u32 rq_vers; /* program version */ 257 u32 rq_proc; /* procedure number */ 258 u32 rq_prot; /* IP protocol */ 259 unsigned short 260 rq_secure : 1; /* secure port */ 261 262 union svc_addr_u rq_daddr; /* dest addr of request 263 * - reply from here */ 264 265 void * rq_argp; /* decoded arguments */ 266 void * rq_resp; /* xdr'd results */ 267 void * rq_auth_data; /* flavor-specific data */ 268 269 int rq_reserved; /* space on socket outq 270 * reserved for this request 271 */ 272 273 struct cache_req rq_chandle; /* handle passed to caches for 274 * request delaying 275 */ 276 /* Catering to nfsd */ 277 struct auth_domain * rq_client; /* RPC peer info */ 278 struct auth_domain * rq_gssclient; /* "gss/"-style peer info */ 279 struct svc_cacherep * rq_cacherep; /* cache info */ 280 struct knfsd_fh * rq_reffh; /* Referrence filehandle, used to 281 * determine what device number 282 * to report (real or virtual) 283 */ 284 int rq_splice_ok; /* turned off in gss privacy 285 * to prevent encrypting page 286 * cache pages */ 287 wait_queue_head_t rq_wait; /* synchronization */ 288 struct task_struct *rq_task; /* service thread */ 289 int rq_waking; /* 1 if thread is being woken */ 290 }; 291 292 /* 293 * Rigorous type checking on sockaddr type conversions 294 */ 295 static inline struct sockaddr_in *svc_addr_in(const struct svc_rqst *rqst) 296 { 297 return (struct sockaddr_in *) &rqst->rq_addr; 298 } 299 300 static inline struct sockaddr_in6 *svc_addr_in6(const struct svc_rqst *rqst) 301 { 302 return (struct sockaddr_in6 *) &rqst->rq_addr; 303 } 304 305 static inline struct sockaddr *svc_addr(const struct svc_rqst *rqst) 306 { 307 return (struct sockaddr *) &rqst->rq_addr; 308 } 309 310 /* 311 * Check buffer bounds after decoding arguments 312 */ 313 static inline int 314 xdr_argsize_check(struct svc_rqst *rqstp, __be32 *p) 315 { 316 char *cp = (char *)p; 317 struct kvec *vec = &rqstp->rq_arg.head[0]; 318 return cp >= (char*)vec->iov_base 319 && cp <= (char*)vec->iov_base + vec->iov_len; 320 } 321 322 static inline int 323 xdr_ressize_check(struct svc_rqst *rqstp, __be32 *p) 324 { 325 struct kvec *vec = &rqstp->rq_res.head[0]; 326 char *cp = (char*)p; 327 328 vec->iov_len = cp - (char*)vec->iov_base; 329 330 return vec->iov_len <= PAGE_SIZE; 331 } 332 333 static inline void svc_free_res_pages(struct svc_rqst *rqstp) 334 { 335 while (rqstp->rq_resused) { 336 struct page **pp = (rqstp->rq_respages + 337 --rqstp->rq_resused); 338 if (*pp) { 339 put_page(*pp); 340 *pp = NULL; 341 } 342 } 343 } 344 345 struct svc_deferred_req { 346 u32 prot; /* protocol (UDP or TCP) */ 347 struct svc_xprt *xprt; 348 struct sockaddr_storage addr; /* where reply must go */ 349 size_t addrlen; 350 union svc_addr_u daddr; /* where reply must come from */ 351 struct cache_deferred_req handle; 352 size_t xprt_hlen; 353 int argslen; 354 __be32 args[0]; 355 }; 356 357 /* 358 * List of RPC programs on the same transport endpoint 359 */ 360 struct svc_program { 361 struct svc_program * pg_next; /* other programs (same xprt) */ 362 u32 pg_prog; /* program number */ 363 unsigned int pg_lovers; /* lowest version */ 364 unsigned int pg_hivers; /* lowest version */ 365 unsigned int pg_nvers; /* number of versions */ 366 struct svc_version ** pg_vers; /* version array */ 367 char * pg_name; /* service name */ 368 char * pg_class; /* class name: services sharing authentication */ 369 struct svc_stat * pg_stats; /* rpc statistics */ 370 int (*pg_authenticate)(struct svc_rqst *); 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 struct svc_procedure * vs_proc; /* per-procedure info */ 380 u32 vs_xdrsize; /* xdrsize needed for this version */ 381 382 unsigned int vs_hidden : 1; /* Don't register with portmapper. 383 * Only used for nfsacl so far. */ 384 385 /* Override dispatch function (e.g. when caching replies). 386 * A return value of 0 means drop the request. 387 * vs_dispatch == NULL means use default dispatcher. 388 */ 389 int (*vs_dispatch)(struct svc_rqst *, __be32 *); 390 }; 391 392 /* 393 * RPC procedure info 394 */ 395 typedef __be32 (*svc_procfunc)(struct svc_rqst *, void *argp, void *resp); 396 struct svc_procedure { 397 svc_procfunc pc_func; /* process the request */ 398 kxdrproc_t pc_decode; /* XDR decode args */ 399 kxdrproc_t pc_encode; /* XDR encode result */ 400 kxdrproc_t pc_release; /* XDR free result */ 401 unsigned int pc_argsize; /* argument struct size */ 402 unsigned int pc_ressize; /* result struct size */ 403 unsigned int pc_count; /* call count */ 404 unsigned int pc_cachetype; /* cache info (NFS) */ 405 unsigned int pc_xdrressize; /* maximum size of XDR reply */ 406 }; 407 408 /* 409 * Function prototypes. 410 */ 411 struct svc_serv *svc_create(struct svc_program *, unsigned int, 412 void (*shutdown)(struct svc_serv *)); 413 struct svc_rqst *svc_prepare_thread(struct svc_serv *serv, 414 struct svc_pool *pool); 415 void svc_exit_thread(struct svc_rqst *); 416 struct svc_serv * svc_create_pooled(struct svc_program *, unsigned int, 417 void (*shutdown)(struct svc_serv *), 418 svc_thread_fn, struct module *); 419 int svc_set_num_threads(struct svc_serv *, struct svc_pool *, int); 420 int svc_pool_stats_open(struct svc_serv *serv, struct file *file); 421 void svc_destroy(struct svc_serv *); 422 int svc_process(struct svc_rqst *); 423 int bc_svc_process(struct svc_serv *, struct rpc_rqst *, 424 struct svc_rqst *); 425 int svc_register(const struct svc_serv *, const int, 426 const unsigned short, const unsigned short); 427 428 void svc_wake_up(struct svc_serv *); 429 void svc_reserve(struct svc_rqst *rqstp, int space); 430 struct svc_pool * svc_pool_for_cpu(struct svc_serv *serv, int cpu); 431 char * svc_print_addr(struct svc_rqst *, char *, size_t); 432 433 #define RPC_MAX_ADDRBUFLEN (63U) 434 435 /* 436 * When we want to reduce the size of the reserved space in the response 437 * buffer, we need to take into account the size of any checksum data that 438 * may be at the end of the packet. This is difficult to determine exactly 439 * for all cases without actually generating the checksum, so we just use a 440 * static value. 441 */ 442 static inline void svc_reserve_auth(struct svc_rqst *rqstp, int space) 443 { 444 int added_space = 0; 445 446 if (rqstp->rq_authop->flavour) 447 added_space = RPC_MAX_AUTH_SIZE; 448 svc_reserve(rqstp, space + added_space); 449 } 450 451 #endif /* SUNRPC_SVC_H */ 452