1 /*
2 * linux/include/linux/sunrpc/svc.h
3 *
4 * RPC server declarations.
5 *
6 * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
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
svc_getu32(struct kvec * iov)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
svc_ungetu32(struct kvec * iov)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
svc_putu32(struct kvec * iov,u32 val)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 int rq_sendfile_ok; /* turned off in gss privacy
163 * to prevent encrypting page
164 * cache pages */
165 wait_queue_head_t rq_wait; /* synchronization */
166 };
167
168 /*
169 * Check buffer bounds after decoding arguments
170 */
171 static inline int
xdr_argsize_check(struct svc_rqst * rqstp,u32 * p)172 xdr_argsize_check(struct svc_rqst *rqstp, u32 *p)
173 {
174 char *cp = (char *)p;
175 struct kvec *vec = &rqstp->rq_arg.head[0];
176 return cp >= (char*)vec->iov_base
177 && cp <= (char*)vec->iov_base + vec->iov_len;
178 }
179
180 static inline int
xdr_ressize_check(struct svc_rqst * rqstp,u32 * p)181 xdr_ressize_check(struct svc_rqst *rqstp, u32 *p)
182 {
183 struct kvec *vec = &rqstp->rq_res.head[0];
184 char *cp = (char*)p;
185
186 vec->iov_len = cp - (char*)vec->iov_base;
187
188 return vec->iov_len <= PAGE_SIZE;
189 }
190
191 static inline struct page *
svc_take_res_page(struct svc_rqst * rqstp)192 svc_take_res_page(struct svc_rqst *rqstp)
193 {
194 if (rqstp->rq_arghi <= rqstp->rq_argused)
195 return NULL;
196 rqstp->rq_arghi--;
197 rqstp->rq_respages[rqstp->rq_resused] =
198 rqstp->rq_argpages[rqstp->rq_arghi];
199 return rqstp->rq_respages[rqstp->rq_resused++];
200 }
201
svc_take_page(struct svc_rqst * rqstp)202 static inline void svc_take_page(struct svc_rqst *rqstp)
203 {
204 if (rqstp->rq_arghi <= rqstp->rq_argused) {
205 WARN_ON(1);
206 return;
207 }
208 rqstp->rq_arghi--;
209 rqstp->rq_respages[rqstp->rq_resused] =
210 rqstp->rq_argpages[rqstp->rq_arghi];
211 rqstp->rq_resused++;
212 }
213
svc_pushback_allpages(struct svc_rqst * rqstp)214 static inline void svc_pushback_allpages(struct svc_rqst *rqstp)
215 {
216 while (rqstp->rq_resused) {
217 if (rqstp->rq_respages[--rqstp->rq_resused] == NULL)
218 continue;
219 rqstp->rq_argpages[rqstp->rq_arghi++] =
220 rqstp->rq_respages[rqstp->rq_resused];
221 rqstp->rq_respages[rqstp->rq_resused] = NULL;
222 }
223 }
224
svc_pushback_unused_pages(struct svc_rqst * rqstp)225 static inline void svc_pushback_unused_pages(struct svc_rqst *rqstp)
226 {
227 while (rqstp->rq_resused &&
228 rqstp->rq_res.pages != &rqstp->rq_respages[rqstp->rq_resused]) {
229
230 if (rqstp->rq_respages[--rqstp->rq_resused] != NULL) {
231 rqstp->rq_argpages[rqstp->rq_arghi++] =
232 rqstp->rq_respages[rqstp->rq_resused];
233 rqstp->rq_respages[rqstp->rq_resused] = NULL;
234 }
235 }
236 }
237
svc_free_allpages(struct svc_rqst * rqstp)238 static inline void svc_free_allpages(struct svc_rqst *rqstp)
239 {
240 while (rqstp->rq_resused) {
241 if (rqstp->rq_respages[--rqstp->rq_resused] == NULL)
242 continue;
243 put_page(rqstp->rq_respages[rqstp->rq_resused]);
244 rqstp->rq_respages[rqstp->rq_resused] = NULL;
245 }
246 }
247
248 struct svc_deferred_req {
249 u32 prot; /* protocol (UDP or TCP) */
250 struct sockaddr_in addr;
251 struct svc_sock *svsk; /* where reply must go */
252 u32 daddr; /* where reply must come from */
253 struct cache_deferred_req handle;
254 int argslen;
255 u32 args[0];
256 };
257
258 /*
259 * List of RPC programs on the same transport endpoint
260 */
261 struct svc_program {
262 struct svc_program * pg_next; /* other programs (same xprt) */
263 u32 pg_prog; /* program number */
264 unsigned int pg_lovers; /* lowest version */
265 unsigned int pg_hivers; /* lowest version */
266 unsigned int pg_nvers; /* number of versions */
267 struct svc_version ** pg_vers; /* version array */
268 char * pg_name; /* service name */
269 char * pg_class; /* class name: services sharing authentication */
270 struct svc_stat * pg_stats; /* rpc statistics */
271 int (*pg_authenticate)(struct svc_rqst *);
272 };
273
274 /*
275 * RPC program version
276 */
277 struct svc_version {
278 u32 vs_vers; /* version number */
279 u32 vs_nproc; /* number of procedures */
280 struct svc_procedure * vs_proc; /* per-procedure info */
281 u32 vs_xdrsize; /* xdrsize needed for this version */
282
283 /* Override dispatch function (e.g. when caching replies).
284 * A return value of 0 means drop the request.
285 * vs_dispatch == NULL means use default dispatcher.
286 */
287 int (*vs_dispatch)(struct svc_rqst *, u32 *);
288 };
289
290 /*
291 * RPC procedure info
292 */
293 typedef int (*svc_procfunc)(struct svc_rqst *, void *argp, void *resp);
294 struct svc_procedure {
295 svc_procfunc pc_func; /* process the request */
296 kxdrproc_t pc_decode; /* XDR decode args */
297 kxdrproc_t pc_encode; /* XDR encode result */
298 kxdrproc_t pc_release; /* XDR free result */
299 unsigned int pc_argsize; /* argument struct size */
300 unsigned int pc_ressize; /* result struct size */
301 unsigned int pc_count; /* call count */
302 unsigned int pc_cachetype; /* cache info (NFS) */
303 unsigned int pc_xdrressize; /* maximum size of XDR reply */
304 };
305
306 /*
307 * This is the RPC server thread function prototype
308 */
309 typedef void (*svc_thread_fn)(struct svc_rqst *);
310
311 /*
312 * Function prototypes.
313 */
314 struct svc_serv * svc_create(struct svc_program *, unsigned int);
315 int svc_create_thread(svc_thread_fn, struct svc_serv *);
316 void svc_exit_thread(struct svc_rqst *);
317 void svc_destroy(struct svc_serv *);
318 int svc_process(struct svc_serv *, struct svc_rqst *);
319 int svc_register(struct svc_serv *, int, unsigned short);
320 void svc_wake_up(struct svc_serv *);
321 void svc_reserve(struct svc_rqst *rqstp, int space);
322
323 #endif /* SUNRPC_SVC_H */
324