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 void (*svc_thread_fn)(struct svc_rqst *); 26 27 /* 28 * 29 * RPC service thread pool. 30 * 31 * Pool of threads and temporary sockets. Generally there is only 32 * a single one of these per RPC service, but on NUMA machines those 33 * services that can benefit from it (i.e. nfs but not lockd) will 34 * have one pool per NUMA node. This optimisation reduces cross- 35 * node traffic on multi-node NUMA NFS servers. 36 */ 37 struct svc_pool { 38 unsigned int sp_id; /* pool id; also node id on NUMA */ 39 spinlock_t sp_lock; /* protects all fields */ 40 struct list_head sp_threads; /* idle server threads */ 41 struct list_head sp_sockets; /* pending sockets */ 42 unsigned int sp_nrthreads; /* # of threads in pool */ 43 struct list_head sp_all_threads; /* all server threads */ 44 } ____cacheline_aligned_in_smp; 45 46 /* 47 * RPC service. 48 * 49 * An RPC service is a ``daemon,'' possibly multithreaded, which 50 * receives and processes incoming RPC messages. 51 * It has one or more transport sockets associated with it, and maintains 52 * a list of idle threads waiting for input. 53 * 54 * We currently do not support more than one RPC program per daemon. 55 */ 56 struct svc_serv { 57 struct svc_program * sv_program; /* RPC program */ 58 struct svc_stat * sv_stats; /* RPC statistics */ 59 spinlock_t sv_lock; 60 unsigned int sv_nrthreads; /* # of server threads */ 61 unsigned int sv_max_payload; /* datagram payload size */ 62 unsigned int sv_max_mesg; /* max_payload + 1 page for overheads */ 63 unsigned int sv_xdrsize; /* XDR buffer size */ 64 65 struct list_head sv_permsocks; /* all permanent sockets */ 66 struct list_head sv_tempsocks; /* all temporary sockets */ 67 int sv_tmpcnt; /* count of temporary sockets */ 68 struct timer_list sv_temptimer; /* timer for aging temporary sockets */ 69 70 char * sv_name; /* service name */ 71 72 unsigned int sv_nrpools; /* number of thread pools */ 73 struct svc_pool * sv_pools; /* array of thread pools */ 74 75 void (*sv_shutdown)(struct svc_serv *serv); 76 /* Callback to use when last thread 77 * exits. 78 */ 79 80 struct module * sv_module; /* optional module to count when 81 * adding threads */ 82 svc_thread_fn sv_function; /* main function for threads */ 83 int sv_kill_signal; /* signal to kill threads */ 84 }; 85 86 /* 87 * We use sv_nrthreads as a reference count. svc_destroy() drops 88 * this refcount, so we need to bump it up around operations that 89 * change the number of threads. Horrible, but there it is. 90 * Should be called with the BKL held. 91 */ 92 static inline void svc_get(struct svc_serv *serv) 93 { 94 serv->sv_nrthreads++; 95 } 96 97 /* 98 * Maximum payload size supported by a kernel RPC server. 99 * This is use to determine the max number of pages nfsd is 100 * willing to return in a single READ operation. 101 * 102 * These happen to all be powers of 2, which is not strictly 103 * necessary but helps enforce the real limitation, which is 104 * that they should be multiples of PAGE_CACHE_SIZE. 105 * 106 * For UDP transports, a block plus NFS,RPC, and UDP headers 107 * has to fit into the IP datagram limit of 64K. The largest 108 * feasible number for all known page sizes is probably 48K, 109 * but we choose 32K here. This is the same as the historical 110 * Linux limit; someone who cares more about NFS/UDP performance 111 * can test a larger number. 112 * 113 * For TCP transports we have more freedom. A size of 1MB is 114 * chosen to match the client limit. Other OSes are known to 115 * have larger limits, but those numbers are probably beyond 116 * the point of diminishing returns. 117 */ 118 #define RPCSVC_MAXPAYLOAD (1*1024*1024u) 119 #define RPCSVC_MAXPAYLOAD_TCP RPCSVC_MAXPAYLOAD 120 #define RPCSVC_MAXPAYLOAD_UDP (32*1024u) 121 122 extern u32 svc_max_payload(const struct svc_rqst *rqstp); 123 124 /* 125 * RPC Requsts and replies are stored in one or more pages. 126 * We maintain an array of pages for each server thread. 127 * Requests are copied into these pages as they arrive. Remaining 128 * pages are available to write the reply into. 129 * 130 * Pages are sent using ->sendpage so each server thread needs to 131 * allocate more to replace those used in sending. To help keep track 132 * of these pages we have a receive list where all pages initialy live, 133 * and a send list where pages are moved to when there are to be part 134 * of a reply. 135 * 136 * We use xdr_buf for holding responses as it fits well with NFS 137 * read responses (that have a header, and some data pages, and possibly 138 * a tail) and means we can share some client side routines. 139 * 140 * The xdr_buf.head kvec always points to the first page in the rq_*pages 141 * list. The xdr_buf.pages pointer points to the second page on that 142 * list. xdr_buf.tail points to the end of the first page. 143 * This assumes that the non-page part of an rpc reply will fit 144 * in a page - NFSd ensures this. lockd also has no trouble. 145 * 146 * Each request/reply pair can have at most one "payload", plus two pages, 147 * one for the request, and one for the reply. 148 * We using ->sendfile to return read data, we might need one extra page 149 * if the request is not page-aligned. So add another '1'. 150 */ 151 #define RPCSVC_MAXPAGES ((RPCSVC_MAXPAYLOAD+PAGE_SIZE-1)/PAGE_SIZE \ 152 + 2 + 1) 153 154 static inline u32 svc_getnl(struct kvec *iov) 155 { 156 __be32 val, *vp; 157 vp = iov->iov_base; 158 val = *vp++; 159 iov->iov_base = (void*)vp; 160 iov->iov_len -= sizeof(__be32); 161 return ntohl(val); 162 } 163 164 static inline void svc_putnl(struct kvec *iov, u32 val) 165 { 166 __be32 *vp = iov->iov_base + iov->iov_len; 167 *vp = htonl(val); 168 iov->iov_len += sizeof(__be32); 169 } 170 171 static inline __be32 svc_getu32(struct kvec *iov) 172 { 173 __be32 val, *vp; 174 vp = iov->iov_base; 175 val = *vp++; 176 iov->iov_base = (void*)vp; 177 iov->iov_len -= sizeof(__be32); 178 return val; 179 } 180 181 static inline void svc_ungetu32(struct kvec *iov) 182 { 183 __be32 *vp = (__be32 *)iov->iov_base; 184 iov->iov_base = (void *)(vp - 1); 185 iov->iov_len += sizeof(*vp); 186 } 187 188 static inline void svc_putu32(struct kvec *iov, __be32 val) 189 { 190 __be32 *vp = iov->iov_base + iov->iov_len; 191 *vp = val; 192 iov->iov_len += sizeof(__be32); 193 } 194 195 union svc_addr_u { 196 struct in_addr addr; 197 struct in6_addr addr6; 198 }; 199 200 /* 201 * The context of a single thread, including the request currently being 202 * processed. 203 */ 204 struct svc_rqst { 205 struct list_head rq_list; /* idle list */ 206 struct list_head rq_all; /* all threads list */ 207 struct svc_xprt * rq_xprt; /* transport ptr */ 208 struct sockaddr_storage rq_addr; /* peer address */ 209 size_t rq_addrlen; 210 211 struct svc_serv * rq_server; /* RPC service definition */ 212 struct svc_pool * rq_pool; /* thread pool */ 213 struct svc_procedure * rq_procinfo; /* procedure info */ 214 struct auth_ops * rq_authop; /* authentication flavour */ 215 u32 rq_flavor; /* pseudoflavor */ 216 struct svc_cred rq_cred; /* auth info */ 217 void * rq_xprt_ctxt; /* transport specific context ptr */ 218 struct svc_deferred_req*rq_deferred; /* deferred request we are replaying */ 219 220 size_t rq_xprt_hlen; /* xprt header len */ 221 struct xdr_buf rq_arg; 222 struct xdr_buf rq_res; 223 struct page * rq_pages[RPCSVC_MAXPAGES]; 224 struct page * *rq_respages; /* points into rq_pages */ 225 int rq_resused; /* number of pages used for result */ 226 227 struct kvec rq_vec[RPCSVC_MAXPAGES]; /* generally useful.. */ 228 229 __be32 rq_xid; /* transmission id */ 230 u32 rq_prog; /* program number */ 231 u32 rq_vers; /* program version */ 232 u32 rq_proc; /* procedure number */ 233 u32 rq_prot; /* IP protocol */ 234 unsigned short 235 rq_secure : 1; /* secure port */ 236 237 union svc_addr_u rq_daddr; /* dest addr of request 238 * - reply from here */ 239 240 void * rq_argp; /* decoded arguments */ 241 void * rq_resp; /* xdr'd results */ 242 void * rq_auth_data; /* flavor-specific data */ 243 244 int rq_reserved; /* space on socket outq 245 * reserved for this request 246 */ 247 248 struct cache_req rq_chandle; /* handle passed to caches for 249 * request delaying 250 */ 251 /* Catering to nfsd */ 252 struct auth_domain * rq_client; /* RPC peer info */ 253 struct auth_domain * rq_gssclient; /* "gss/"-style peer info */ 254 struct svc_cacherep * rq_cacherep; /* cache info */ 255 struct knfsd_fh * rq_reffh; /* Referrence filehandle, used to 256 * determine what device number 257 * to report (real or virtual) 258 */ 259 int rq_splice_ok; /* turned off in gss privacy 260 * to prevent encrypting page 261 * cache pages */ 262 wait_queue_head_t rq_wait; /* synchronization */ 263 struct task_struct *rq_task; /* service thread */ 264 }; 265 266 /* 267 * Rigorous type checking on sockaddr type conversions 268 */ 269 static inline struct sockaddr_in *svc_addr_in(struct svc_rqst *rqst) 270 { 271 return (struct sockaddr_in *) &rqst->rq_addr; 272 } 273 274 static inline struct sockaddr_in6 *svc_addr_in6(struct svc_rqst *rqst) 275 { 276 return (struct sockaddr_in6 *) &rqst->rq_addr; 277 } 278 279 static inline struct sockaddr *svc_addr(struct svc_rqst *rqst) 280 { 281 return (struct sockaddr *) &rqst->rq_addr; 282 } 283 284 /* 285 * Check buffer bounds after decoding arguments 286 */ 287 static inline int 288 xdr_argsize_check(struct svc_rqst *rqstp, __be32 *p) 289 { 290 char *cp = (char *)p; 291 struct kvec *vec = &rqstp->rq_arg.head[0]; 292 return cp >= (char*)vec->iov_base 293 && cp <= (char*)vec->iov_base + vec->iov_len; 294 } 295 296 static inline int 297 xdr_ressize_check(struct svc_rqst *rqstp, __be32 *p) 298 { 299 struct kvec *vec = &rqstp->rq_res.head[0]; 300 char *cp = (char*)p; 301 302 vec->iov_len = cp - (char*)vec->iov_base; 303 304 return vec->iov_len <= PAGE_SIZE; 305 } 306 307 static inline void svc_free_res_pages(struct svc_rqst *rqstp) 308 { 309 while (rqstp->rq_resused) { 310 struct page **pp = (rqstp->rq_respages + 311 --rqstp->rq_resused); 312 if (*pp) { 313 put_page(*pp); 314 *pp = NULL; 315 } 316 } 317 } 318 319 struct svc_deferred_req { 320 u32 prot; /* protocol (UDP or TCP) */ 321 struct svc_xprt *xprt; 322 struct sockaddr_storage addr; /* where reply must go */ 323 size_t addrlen; 324 union svc_addr_u daddr; /* where reply must come from */ 325 struct cache_deferred_req handle; 326 size_t xprt_hlen; 327 int argslen; 328 __be32 args[0]; 329 }; 330 331 /* 332 * List of RPC programs on the same transport endpoint 333 */ 334 struct svc_program { 335 struct svc_program * pg_next; /* other programs (same xprt) */ 336 u32 pg_prog; /* program number */ 337 unsigned int pg_lovers; /* lowest version */ 338 unsigned int pg_hivers; /* lowest version */ 339 unsigned int pg_nvers; /* number of versions */ 340 struct svc_version ** pg_vers; /* version array */ 341 char * pg_name; /* service name */ 342 char * pg_class; /* class name: services sharing authentication */ 343 struct svc_stat * pg_stats; /* rpc statistics */ 344 int (*pg_authenticate)(struct svc_rqst *); 345 }; 346 347 /* 348 * RPC program version 349 */ 350 struct svc_version { 351 u32 vs_vers; /* version number */ 352 u32 vs_nproc; /* number of procedures */ 353 struct svc_procedure * vs_proc; /* per-procedure info */ 354 u32 vs_xdrsize; /* xdrsize needed for this version */ 355 356 unsigned int vs_hidden : 1; /* Don't register with portmapper. 357 * Only used for nfsacl so far. */ 358 359 /* Override dispatch function (e.g. when caching replies). 360 * A return value of 0 means drop the request. 361 * vs_dispatch == NULL means use default dispatcher. 362 */ 363 int (*vs_dispatch)(struct svc_rqst *, __be32 *); 364 }; 365 366 /* 367 * RPC procedure info 368 */ 369 typedef __be32 (*svc_procfunc)(struct svc_rqst *, void *argp, void *resp); 370 struct svc_procedure { 371 svc_procfunc pc_func; /* process the request */ 372 kxdrproc_t pc_decode; /* XDR decode args */ 373 kxdrproc_t pc_encode; /* XDR encode result */ 374 kxdrproc_t pc_release; /* XDR free result */ 375 unsigned int pc_argsize; /* argument struct size */ 376 unsigned int pc_ressize; /* result struct size */ 377 unsigned int pc_count; /* call count */ 378 unsigned int pc_cachetype; /* cache info (NFS) */ 379 unsigned int pc_xdrressize; /* maximum size of XDR reply */ 380 }; 381 382 /* 383 * Function prototypes. 384 */ 385 struct svc_serv * svc_create(struct svc_program *, unsigned int, 386 void (*shutdown)(struct svc_serv*)); 387 struct svc_rqst *svc_prepare_thread(struct svc_serv *serv, 388 struct svc_pool *pool); 389 int svc_create_thread(svc_thread_fn, struct svc_serv *); 390 void svc_exit_thread(struct svc_rqst *); 391 struct svc_serv * svc_create_pooled(struct svc_program *, unsigned int, 392 void (*shutdown)(struct svc_serv*), 393 svc_thread_fn, int sig, struct module *); 394 int svc_set_num_threads(struct svc_serv *, struct svc_pool *, int); 395 void svc_destroy(struct svc_serv *); 396 int svc_process(struct svc_rqst *); 397 int svc_register(struct svc_serv *, int, unsigned short); 398 void svc_wake_up(struct svc_serv *); 399 void svc_reserve(struct svc_rqst *rqstp, int space); 400 struct svc_pool * svc_pool_for_cpu(struct svc_serv *serv, int cpu); 401 char * svc_print_addr(struct svc_rqst *, char *, size_t); 402 403 #define RPC_MAX_ADDRBUFLEN (63U) 404 405 /* 406 * When we want to reduce the size of the reserved space in the response 407 * buffer, we need to take into account the size of any checksum data that 408 * may be at the end of the packet. This is difficult to determine exactly 409 * for all cases without actually generating the checksum, so we just use a 410 * static value. 411 */ 412 static inline void 413 svc_reserve_auth(struct svc_rqst *rqstp, int space) 414 { 415 int added_space = 0; 416 417 switch(rqstp->rq_authop->flavour) { 418 case RPC_AUTH_GSS: 419 added_space = RPC_MAX_AUTH_SIZE; 420 } 421 return svc_reserve(rqstp, space + added_space); 422 } 423 424 #endif /* SUNRPC_SVC_H */ 425