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/sunrpc/types.h> 15 #include <linux/sunrpc/xdr.h> 16 #include <linux/sunrpc/svcauth.h> 17 #include <linux/wait.h> 18 #include <linux/mm.h> 19 20 /* 21 * RPC service. 22 * 23 * An RPC service is a ``daemon,'' possibly multithreaded, which 24 * receives and processes incoming RPC messages. 25 * It has one or more transport sockets associated with it, and maintains 26 * a list of idle threads waiting for input. 27 * 28 * We currently do not support more than one RPC program per daemon. 29 */ 30 struct svc_serv { 31 struct list_head sv_threads; /* idle server threads */ 32 struct list_head sv_sockets; /* pending sockets */ 33 struct svc_program * sv_program; /* RPC program */ 34 struct svc_stat * sv_stats; /* RPC statistics */ 35 spinlock_t sv_lock; 36 unsigned int sv_nrthreads; /* # of server threads */ 37 unsigned int sv_bufsz; /* datagram buffer size */ 38 unsigned int sv_xdrsize; /* XDR buffer size */ 39 40 struct list_head sv_permsocks; /* all permanent sockets */ 41 struct list_head sv_tempsocks; /* all temporary sockets */ 42 int sv_tmpcnt; /* count of temporary sockets */ 43 44 char * sv_name; /* service name */ 45 }; 46 47 /* 48 * Maximum payload size supported by a kernel RPC server. 49 * This is use to determine the max number of pages nfsd is 50 * willing to return in a single READ operation. 51 */ 52 #define RPCSVC_MAXPAYLOAD (64*1024u) 53 54 /* 55 * RPC Requsts and replies are stored in one or more pages. 56 * We maintain an array of pages for each server thread. 57 * Requests are copied into these pages as they arrive. Remaining 58 * pages are available to write the reply into. 59 * 60 * Pages are sent using ->sendpage so each server thread needs to 61 * allocate more to replace those used in sending. To help keep track 62 * of these pages we have a receive list where all pages initialy live, 63 * and a send list where pages are moved to when there are to be part 64 * of a reply. 65 * 66 * We use xdr_buf for holding responses as it fits well with NFS 67 * read responses (that have a header, and some data pages, and possibly 68 * a tail) and means we can share some client side routines. 69 * 70 * The xdr_buf.head kvec always points to the first page in the rq_*pages 71 * list. The xdr_buf.pages pointer points to the second page on that 72 * list. xdr_buf.tail points to the end of the first page. 73 * This assumes that the non-page part of an rpc reply will fit 74 * in a page - NFSd ensures this. lockd also has no trouble. 75 * 76 * Each request/reply pair can have at most one "payload", plus two pages, 77 * one for the request, and one for the reply. 78 */ 79 #define RPCSVC_MAXPAGES ((RPCSVC_MAXPAYLOAD+PAGE_SIZE-1)/PAGE_SIZE + 2) 80 81 static inline u32 svc_getu32(struct kvec *iov) 82 { 83 u32 val, *vp; 84 vp = iov->iov_base; 85 val = *vp++; 86 iov->iov_base = (void*)vp; 87 iov->iov_len -= sizeof(u32); 88 return val; 89 } 90 91 static inline void svc_ungetu32(struct kvec *iov) 92 { 93 u32 *vp = (u32 *)iov->iov_base; 94 iov->iov_base = (void *)(vp - 1); 95 iov->iov_len += sizeof(*vp); 96 } 97 98 static inline void svc_putu32(struct kvec *iov, u32 val) 99 { 100 u32 *vp = iov->iov_base + iov->iov_len; 101 *vp = val; 102 iov->iov_len += sizeof(u32); 103 } 104 105 106 /* 107 * The context of a single thread, including the request currently being 108 * processed. 109 * NOTE: First two items must be prev/next. 110 */ 111 struct svc_rqst { 112 struct list_head rq_list; /* idle list */ 113 struct svc_sock * rq_sock; /* socket */ 114 struct sockaddr_in rq_addr; /* peer address */ 115 int rq_addrlen; 116 117 struct svc_serv * rq_server; /* RPC service definition */ 118 struct svc_procedure * rq_procinfo; /* procedure info */ 119 struct auth_ops * rq_authop; /* authentication flavour */ 120 struct svc_cred rq_cred; /* auth info */ 121 struct sk_buff * rq_skbuff; /* fast recv inet buffer */ 122 struct svc_deferred_req*rq_deferred; /* deferred request we are replaying */ 123 124 struct xdr_buf rq_arg; 125 struct xdr_buf rq_res; 126 struct page * rq_argpages[RPCSVC_MAXPAGES]; 127 struct page * rq_respages[RPCSVC_MAXPAGES]; 128 int rq_restailpage; 129 short rq_argused; /* pages used for argument */ 130 short rq_arghi; /* pages available in argument page list */ 131 short rq_resused; /* pages used for result */ 132 133 u32 rq_xid; /* transmission id */ 134 u32 rq_prog; /* program number */ 135 u32 rq_vers; /* program version */ 136 u32 rq_proc; /* procedure number */ 137 u32 rq_prot; /* IP protocol */ 138 unsigned short 139 rq_secure : 1; /* secure port */ 140 141 142 __u32 rq_daddr; /* dest addr of request - reply from here */ 143 144 void * rq_argp; /* decoded arguments */ 145 void * rq_resp; /* xdr'd results */ 146 void * rq_auth_data; /* flavor-specific data */ 147 148 int rq_reserved; /* space on socket outq 149 * reserved for this request 150 */ 151 152 struct cache_req rq_chandle; /* handle passed to caches for 153 * request delaying 154 */ 155 /* Catering to nfsd */ 156 struct auth_domain * rq_client; /* RPC peer info */ 157 struct svc_cacherep * rq_cacherep; /* cache info */ 158 struct knfsd_fh * rq_reffh; /* Referrence filehandle, used to 159 * determine what device number 160 * to report (real or virtual) 161 */ 162 163 wait_queue_head_t rq_wait; /* synchronization */ 164 }; 165 166 /* 167 * Check buffer bounds after decoding arguments 168 */ 169 static inline int 170 xdr_argsize_check(struct svc_rqst *rqstp, u32 *p) 171 { 172 char *cp = (char *)p; 173 struct kvec *vec = &rqstp->rq_arg.head[0]; 174 return cp >= (char*)vec->iov_base 175 && cp <= (char*)vec->iov_base + vec->iov_len; 176 } 177 178 static inline int 179 xdr_ressize_check(struct svc_rqst *rqstp, u32 *p) 180 { 181 struct kvec *vec = &rqstp->rq_res.head[0]; 182 char *cp = (char*)p; 183 184 vec->iov_len = cp - (char*)vec->iov_base; 185 186 return vec->iov_len <= PAGE_SIZE; 187 } 188 189 static inline struct page * 190 svc_take_res_page(struct svc_rqst *rqstp) 191 { 192 if (rqstp->rq_arghi <= rqstp->rq_argused) 193 return NULL; 194 rqstp->rq_arghi--; 195 rqstp->rq_respages[rqstp->rq_resused] = 196 rqstp->rq_argpages[rqstp->rq_arghi]; 197 return rqstp->rq_respages[rqstp->rq_resused++]; 198 } 199 200 static inline int svc_take_page(struct svc_rqst *rqstp) 201 { 202 if (rqstp->rq_arghi <= rqstp->rq_argused) 203 return -ENOMEM; 204 rqstp->rq_arghi--; 205 rqstp->rq_respages[rqstp->rq_resused] = 206 rqstp->rq_argpages[rqstp->rq_arghi]; 207 rqstp->rq_resused++; 208 return 0; 209 } 210 211 static inline void svc_pushback_allpages(struct svc_rqst *rqstp) 212 { 213 while (rqstp->rq_resused) { 214 if (rqstp->rq_respages[--rqstp->rq_resused] == NULL) 215 continue; 216 rqstp->rq_argpages[rqstp->rq_arghi++] = 217 rqstp->rq_respages[rqstp->rq_resused]; 218 rqstp->rq_respages[rqstp->rq_resused] = NULL; 219 } 220 } 221 222 static inline void svc_pushback_unused_pages(struct svc_rqst *rqstp) 223 { 224 while (rqstp->rq_resused && 225 rqstp->rq_res.pages != &rqstp->rq_respages[rqstp->rq_resused]) { 226 227 if (rqstp->rq_respages[--rqstp->rq_resused] != NULL) { 228 rqstp->rq_argpages[rqstp->rq_arghi++] = 229 rqstp->rq_respages[rqstp->rq_resused]; 230 rqstp->rq_respages[rqstp->rq_resused] = NULL; 231 } 232 } 233 } 234 235 static inline void svc_free_allpages(struct svc_rqst *rqstp) 236 { 237 while (rqstp->rq_resused) { 238 if (rqstp->rq_respages[--rqstp->rq_resused] == NULL) 239 continue; 240 put_page(rqstp->rq_respages[rqstp->rq_resused]); 241 rqstp->rq_respages[rqstp->rq_resused] = NULL; 242 } 243 } 244 245 struct svc_deferred_req { 246 u32 prot; /* protocol (UDP or TCP) */ 247 struct sockaddr_in addr; 248 struct svc_sock *svsk; /* where reply must go */ 249 struct cache_deferred_req handle; 250 int argslen; 251 u32 args[0]; 252 }; 253 254 /* 255 * List of RPC programs on the same transport endpoint 256 */ 257 struct svc_program { 258 struct svc_program * pg_next; /* other programs (same xprt) */ 259 u32 pg_prog; /* program number */ 260 unsigned int pg_lovers; /* lowest version */ 261 unsigned int pg_hivers; /* lowest version */ 262 unsigned int pg_nvers; /* number of versions */ 263 struct svc_version ** pg_vers; /* version array */ 264 char * pg_name; /* service name */ 265 char * pg_class; /* class name: services sharing authentication */ 266 struct svc_stat * pg_stats; /* rpc statistics */ 267 int (*pg_authenticate)(struct svc_rqst *); 268 }; 269 270 /* 271 * RPC program version 272 */ 273 struct svc_version { 274 u32 vs_vers; /* version number */ 275 u32 vs_nproc; /* number of procedures */ 276 struct svc_procedure * vs_proc; /* per-procedure info */ 277 u32 vs_xdrsize; /* xdrsize needed for this version */ 278 279 /* Override dispatch function (e.g. when caching replies). 280 * A return value of 0 means drop the request. 281 * vs_dispatch == NULL means use default dispatcher. 282 */ 283 int (*vs_dispatch)(struct svc_rqst *, u32 *); 284 }; 285 286 /* 287 * RPC procedure info 288 */ 289 typedef int (*svc_procfunc)(struct svc_rqst *, void *argp, void *resp); 290 struct svc_procedure { 291 svc_procfunc pc_func; /* process the request */ 292 kxdrproc_t pc_decode; /* XDR decode args */ 293 kxdrproc_t pc_encode; /* XDR encode result */ 294 kxdrproc_t pc_release; /* XDR free result */ 295 unsigned int pc_argsize; /* argument struct size */ 296 unsigned int pc_ressize; /* result struct size */ 297 unsigned int pc_count; /* call count */ 298 unsigned int pc_cachetype; /* cache info (NFS) */ 299 unsigned int pc_xdrressize; /* maximum size of XDR reply */ 300 }; 301 302 /* 303 * This is the RPC server thread function prototype 304 */ 305 typedef void (*svc_thread_fn)(struct svc_rqst *); 306 307 /* 308 * Function prototypes. 309 */ 310 struct svc_serv * svc_create(struct svc_program *, unsigned int); 311 int svc_create_thread(svc_thread_fn, struct svc_serv *); 312 void svc_exit_thread(struct svc_rqst *); 313 void svc_destroy(struct svc_serv *); 314 int svc_process(struct svc_serv *, struct svc_rqst *); 315 int svc_register(struct svc_serv *, int, unsigned short); 316 void svc_wake_up(struct svc_serv *); 317 void svc_reserve(struct svc_rqst *rqstp, int space); 318 319 #endif /* SUNRPC_SVC_H */ 320