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 /* 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_maxconn; /* max connections allowed or 62 * '0' causing max to be based 63 * on number of threads. */ 64 65 unsigned int sv_max_payload; /* datagram payload size */ 66 unsigned int sv_max_mesg; /* max_payload + 1 page for overheads */ 67 unsigned int sv_xdrsize; /* XDR buffer size */ 68 struct list_head sv_permsocks; /* all permanent sockets */ 69 struct list_head sv_tempsocks; /* all temporary sockets */ 70 int sv_tmpcnt; /* count of temporary sockets */ 71 struct timer_list sv_temptimer; /* timer for aging temporary sockets */ 72 sa_family_t sv_family; /* listener's address family */ 73 74 char * sv_name; /* service name */ 75 76 unsigned int sv_nrpools; /* number of thread pools */ 77 struct svc_pool * sv_pools; /* array of thread pools */ 78 79 void (*sv_shutdown)(struct svc_serv *serv); 80 /* Callback to use when last thread 81 * exits. 82 */ 83 84 struct module * sv_module; /* optional module to count when 85 * adding threads */ 86 svc_thread_fn sv_function; /* main function for threads */ 87 }; 88 89 /* 90 * We use sv_nrthreads as a reference count. svc_destroy() drops 91 * this refcount, so we need to bump it up around operations that 92 * change the number of threads. Horrible, but there it is. 93 * Should be called with the BKL held. 94 */ 95 static inline void svc_get(struct svc_serv *serv) 96 { 97 serv->sv_nrthreads++; 98 } 99 100 /* 101 * Maximum payload size supported by a kernel RPC server. 102 * This is use to determine the max number of pages nfsd is 103 * willing to return in a single READ operation. 104 * 105 * These happen to all be powers of 2, which is not strictly 106 * necessary but helps enforce the real limitation, which is 107 * that they should be multiples of PAGE_CACHE_SIZE. 108 * 109 * For UDP transports, a block plus NFS,RPC, and UDP headers 110 * has to fit into the IP datagram limit of 64K. The largest 111 * feasible number for all known page sizes is probably 48K, 112 * but we choose 32K here. This is the same as the historical 113 * Linux limit; someone who cares more about NFS/UDP performance 114 * can test a larger number. 115 * 116 * For TCP transports we have more freedom. A size of 1MB is 117 * chosen to match the client limit. Other OSes are known to 118 * have larger limits, but those numbers are probably beyond 119 * the point of diminishing returns. 120 */ 121 #define RPCSVC_MAXPAYLOAD (1*1024*1024u) 122 #define RPCSVC_MAXPAYLOAD_TCP RPCSVC_MAXPAYLOAD 123 #define RPCSVC_MAXPAYLOAD_UDP (32*1024u) 124 125 extern u32 svc_max_payload(const struct svc_rqst *rqstp); 126 127 /* 128 * RPC Requsts and replies are stored in one or more pages. 129 * We maintain an array of pages for each server thread. 130 * Requests are copied into these pages as they arrive. Remaining 131 * pages are available to write the reply into. 132 * 133 * Pages are sent using ->sendpage so each server thread needs to 134 * allocate more to replace those used in sending. To help keep track 135 * of these pages we have a receive list where all pages initialy live, 136 * and a send list where pages are moved to when there are to be part 137 * of a reply. 138 * 139 * We use xdr_buf for holding responses as it fits well with NFS 140 * read responses (that have a header, and some data pages, and possibly 141 * a tail) and means we can share some client side routines. 142 * 143 * The xdr_buf.head kvec always points to the first page in the rq_*pages 144 * list. The xdr_buf.pages pointer points to the second page on that 145 * list. xdr_buf.tail points to the end of the first page. 146 * This assumes that the non-page part of an rpc reply will fit 147 * in a page - NFSd ensures this. lockd also has no trouble. 148 * 149 * Each request/reply pair can have at most one "payload", plus two pages, 150 * one for the request, and one for the reply. 151 * We using ->sendfile to return read data, we might need one extra page 152 * if the request is not page-aligned. So add another '1'. 153 */ 154 #define RPCSVC_MAXPAGES ((RPCSVC_MAXPAYLOAD+PAGE_SIZE-1)/PAGE_SIZE \ 155 + 2 + 1) 156 157 static inline u32 svc_getnl(struct kvec *iov) 158 { 159 __be32 val, *vp; 160 vp = iov->iov_base; 161 val = *vp++; 162 iov->iov_base = (void*)vp; 163 iov->iov_len -= sizeof(__be32); 164 return ntohl(val); 165 } 166 167 static inline void svc_putnl(struct kvec *iov, u32 val) 168 { 169 __be32 *vp = iov->iov_base + iov->iov_len; 170 *vp = htonl(val); 171 iov->iov_len += sizeof(__be32); 172 } 173 174 static inline __be32 svc_getu32(struct kvec *iov) 175 { 176 __be32 val, *vp; 177 vp = iov->iov_base; 178 val = *vp++; 179 iov->iov_base = (void*)vp; 180 iov->iov_len -= sizeof(__be32); 181 return val; 182 } 183 184 static inline void svc_ungetu32(struct kvec *iov) 185 { 186 __be32 *vp = (__be32 *)iov->iov_base; 187 iov->iov_base = (void *)(vp - 1); 188 iov->iov_len += sizeof(*vp); 189 } 190 191 static inline void svc_putu32(struct kvec *iov, __be32 val) 192 { 193 __be32 *vp = iov->iov_base + iov->iov_len; 194 *vp = val; 195 iov->iov_len += sizeof(__be32); 196 } 197 198 union svc_addr_u { 199 struct in_addr addr; 200 struct in6_addr addr6; 201 }; 202 203 /* 204 * The context of a single thread, including the request currently being 205 * processed. 206 */ 207 struct svc_rqst { 208 struct list_head rq_list; /* idle list */ 209 struct list_head rq_all; /* all threads list */ 210 struct svc_xprt * rq_xprt; /* transport ptr */ 211 struct sockaddr_storage rq_addr; /* peer address */ 212 size_t rq_addrlen; 213 214 struct svc_serv * rq_server; /* RPC service definition */ 215 struct svc_pool * rq_pool; /* thread pool */ 216 struct svc_procedure * rq_procinfo; /* procedure info */ 217 struct auth_ops * rq_authop; /* authentication flavour */ 218 u32 rq_flavor; /* pseudoflavor */ 219 struct svc_cred rq_cred; /* auth info */ 220 void * rq_xprt_ctxt; /* transport specific context ptr */ 221 struct svc_deferred_req*rq_deferred; /* deferred request we are replaying */ 222 223 size_t rq_xprt_hlen; /* xprt header len */ 224 struct xdr_buf rq_arg; 225 struct xdr_buf rq_res; 226 struct page * rq_pages[RPCSVC_MAXPAGES]; 227 struct page * *rq_respages; /* points into rq_pages */ 228 int rq_resused; /* number of pages used for result */ 229 230 struct kvec rq_vec[RPCSVC_MAXPAGES]; /* generally useful.. */ 231 232 __be32 rq_xid; /* transmission id */ 233 u32 rq_prog; /* program number */ 234 u32 rq_vers; /* program version */ 235 u32 rq_proc; /* procedure number */ 236 u32 rq_prot; /* IP protocol */ 237 unsigned short 238 rq_secure : 1; /* secure port */ 239 240 union svc_addr_u rq_daddr; /* dest addr of request 241 * - reply from here */ 242 243 void * rq_argp; /* decoded arguments */ 244 void * rq_resp; /* xdr'd results */ 245 void * rq_auth_data; /* flavor-specific data */ 246 247 int rq_reserved; /* space on socket outq 248 * reserved for this request 249 */ 250 251 struct cache_req rq_chandle; /* handle passed to caches for 252 * request delaying 253 */ 254 /* Catering to nfsd */ 255 struct auth_domain * rq_client; /* RPC peer info */ 256 struct auth_domain * rq_gssclient; /* "gss/"-style peer info */ 257 struct svc_cacherep * rq_cacherep; /* cache info */ 258 struct knfsd_fh * rq_reffh; /* Referrence filehandle, used to 259 * determine what device number 260 * to report (real or virtual) 261 */ 262 int rq_splice_ok; /* turned off in gss privacy 263 * to prevent encrypting page 264 * cache pages */ 265 wait_queue_head_t rq_wait; /* synchronization */ 266 struct task_struct *rq_task; /* service thread */ 267 }; 268 269 /* 270 * Rigorous type checking on sockaddr type conversions 271 */ 272 static inline struct sockaddr_in *svc_addr_in(const struct svc_rqst *rqst) 273 { 274 return (struct sockaddr_in *) &rqst->rq_addr; 275 } 276 277 static inline struct sockaddr_in6 *svc_addr_in6(const struct svc_rqst *rqst) 278 { 279 return (struct sockaddr_in6 *) &rqst->rq_addr; 280 } 281 282 static inline struct sockaddr *svc_addr(const struct svc_rqst *rqst) 283 { 284 return (struct sockaddr *) &rqst->rq_addr; 285 } 286 287 /* 288 * Check buffer bounds after decoding arguments 289 */ 290 static inline int 291 xdr_argsize_check(struct svc_rqst *rqstp, __be32 *p) 292 { 293 char *cp = (char *)p; 294 struct kvec *vec = &rqstp->rq_arg.head[0]; 295 return cp >= (char*)vec->iov_base 296 && cp <= (char*)vec->iov_base + vec->iov_len; 297 } 298 299 static inline int 300 xdr_ressize_check(struct svc_rqst *rqstp, __be32 *p) 301 { 302 struct kvec *vec = &rqstp->rq_res.head[0]; 303 char *cp = (char*)p; 304 305 vec->iov_len = cp - (char*)vec->iov_base; 306 307 return vec->iov_len <= PAGE_SIZE; 308 } 309 310 static inline void svc_free_res_pages(struct svc_rqst *rqstp) 311 { 312 while (rqstp->rq_resused) { 313 struct page **pp = (rqstp->rq_respages + 314 --rqstp->rq_resused); 315 if (*pp) { 316 put_page(*pp); 317 *pp = NULL; 318 } 319 } 320 } 321 322 struct svc_deferred_req { 323 u32 prot; /* protocol (UDP or TCP) */ 324 struct svc_xprt *xprt; 325 struct sockaddr_storage addr; /* where reply must go */ 326 size_t addrlen; 327 union svc_addr_u daddr; /* where reply must come from */ 328 struct cache_deferred_req handle; 329 size_t xprt_hlen; 330 int argslen; 331 __be32 args[0]; 332 }; 333 334 /* 335 * List of RPC programs on the same transport endpoint 336 */ 337 struct svc_program { 338 struct svc_program * pg_next; /* other programs (same xprt) */ 339 u32 pg_prog; /* program number */ 340 unsigned int pg_lovers; /* lowest version */ 341 unsigned int pg_hivers; /* lowest version */ 342 unsigned int pg_nvers; /* number of versions */ 343 struct svc_version ** pg_vers; /* version array */ 344 char * pg_name; /* service name */ 345 char * pg_class; /* class name: services sharing authentication */ 346 struct svc_stat * pg_stats; /* rpc statistics */ 347 int (*pg_authenticate)(struct svc_rqst *); 348 }; 349 350 /* 351 * RPC program version 352 */ 353 struct svc_version { 354 u32 vs_vers; /* version number */ 355 u32 vs_nproc; /* number of procedures */ 356 struct svc_procedure * vs_proc; /* per-procedure info */ 357 u32 vs_xdrsize; /* xdrsize needed for this version */ 358 359 unsigned int vs_hidden : 1; /* Don't register with portmapper. 360 * Only used for nfsacl so far. */ 361 362 /* Override dispatch function (e.g. when caching replies). 363 * A return value of 0 means drop the request. 364 * vs_dispatch == NULL means use default dispatcher. 365 */ 366 int (*vs_dispatch)(struct svc_rqst *, __be32 *); 367 }; 368 369 /* 370 * RPC procedure info 371 */ 372 typedef __be32 (*svc_procfunc)(struct svc_rqst *, void *argp, void *resp); 373 struct svc_procedure { 374 svc_procfunc pc_func; /* process the request */ 375 kxdrproc_t pc_decode; /* XDR decode args */ 376 kxdrproc_t pc_encode; /* XDR encode result */ 377 kxdrproc_t pc_release; /* XDR free result */ 378 unsigned int pc_argsize; /* argument struct size */ 379 unsigned int pc_ressize; /* result struct size */ 380 unsigned int pc_count; /* call count */ 381 unsigned int pc_cachetype; /* cache info (NFS) */ 382 unsigned int pc_xdrressize; /* maximum size of XDR reply */ 383 }; 384 385 /* 386 * Function prototypes. 387 */ 388 struct svc_serv *svc_create(struct svc_program *, unsigned int, sa_family_t, 389 void (*shutdown)(struct svc_serv *)); 390 struct svc_rqst *svc_prepare_thread(struct svc_serv *serv, 391 struct svc_pool *pool); 392 void svc_exit_thread(struct svc_rqst *); 393 struct svc_serv * svc_create_pooled(struct svc_program *, unsigned int, 394 sa_family_t, void (*shutdown)(struct svc_serv *), 395 svc_thread_fn, struct module *); 396 int svc_set_num_threads(struct svc_serv *, struct svc_pool *, int); 397 void svc_destroy(struct svc_serv *); 398 int svc_process(struct svc_rqst *); 399 int svc_register(const struct svc_serv *, const unsigned short, 400 const unsigned short); 401 402 void svc_wake_up(struct svc_serv *); 403 void svc_reserve(struct svc_rqst *rqstp, int space); 404 struct svc_pool * svc_pool_for_cpu(struct svc_serv *serv, int cpu); 405 char * svc_print_addr(struct svc_rqst *, char *, size_t); 406 407 #define RPC_MAX_ADDRBUFLEN (63U) 408 409 /* 410 * When we want to reduce the size of the reserved space in the response 411 * buffer, we need to take into account the size of any checksum data that 412 * may be at the end of the packet. This is difficult to determine exactly 413 * for all cases without actually generating the checksum, so we just use a 414 * static value. 415 */ 416 static inline void svc_reserve_auth(struct svc_rqst *rqstp, int space) 417 { 418 int added_space = 0; 419 420 if (rqstp->rq_authop->flavour) 421 added_space = RPC_MAX_AUTH_SIZE; 422 svc_reserve(rqstp, space + added_space); 423 } 424 425 #endif /* SUNRPC_SVC_H */ 426