]>
Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * linux/fs/nfsd/nfssvc.c | |
3 | * | |
4 | * Central processing for nfsd. | |
5 | * | |
6 | * Authors: Olaf Kirch (okir@monad.swb.de) | |
7 | * | |
8 | * Copyright (C) 1995, 1996, 1997 Olaf Kirch <okir@monad.swb.de> | |
9 | */ | |
10 | ||
11 | #include <linux/config.h> | |
12 | #include <linux/module.h> | |
13 | ||
14 | #include <linux/time.h> | |
15 | #include <linux/errno.h> | |
16 | #include <linux/nfs.h> | |
17 | #include <linux/in.h> | |
18 | #include <linux/uio.h> | |
19 | #include <linux/unistd.h> | |
20 | #include <linux/slab.h> | |
21 | #include <linux/smp.h> | |
22 | #include <linux/smp_lock.h> | |
23 | #include <linux/fs_struct.h> | |
24 | ||
25 | #include <linux/sunrpc/types.h> | |
26 | #include <linux/sunrpc/stats.h> | |
27 | #include <linux/sunrpc/svc.h> | |
28 | #include <linux/sunrpc/svcsock.h> | |
29 | #include <linux/sunrpc/cache.h> | |
30 | #include <linux/nfsd/nfsd.h> | |
31 | #include <linux/nfsd/stats.h> | |
32 | #include <linux/nfsd/cache.h> | |
70c3b76c | 33 | #include <linux/nfsd/syscall.h> |
1da177e4 | 34 | #include <linux/lockd/bind.h> |
a257cdd0 | 35 | #include <linux/nfsacl.h> |
1da177e4 LT |
36 | |
37 | #define NFSDDBG_FACILITY NFSDDBG_SVC | |
38 | ||
39 | /* these signals will be delivered to an nfsd thread | |
40 | * when handling a request | |
41 | */ | |
42 | #define ALLOWED_SIGS (sigmask(SIGKILL)) | |
43 | /* these signals will be delivered to an nfsd thread | |
44 | * when not handling a request. i.e. when waiting | |
45 | */ | |
46 | #define SHUTDOWN_SIGS (sigmask(SIGKILL) | sigmask(SIGHUP) | sigmask(SIGINT) | sigmask(SIGQUIT)) | |
47 | /* if the last thread dies with SIGHUP, then the exports table is | |
48 | * left unchanged ( like 2.4-{0-9} ). Any other signal will clear | |
49 | * the exports table (like 2.2). | |
50 | */ | |
51 | #define SIG_NOCLEAN SIGHUP | |
52 | ||
53 | extern struct svc_program nfsd_program; | |
54 | static void nfsd(struct svc_rqst *rqstp); | |
55 | struct timeval nfssvc_boot; | |
70c3b76c | 56 | struct svc_serv *nfsd_serv; |
1da177e4 LT |
57 | static atomic_t nfsd_busy; |
58 | static unsigned long nfsd_last_call; | |
59 | static DEFINE_SPINLOCK(nfsd_call_lock); | |
60 | ||
61 | struct nfsd_list { | |
62 | struct list_head list; | |
63 | struct task_struct *task; | |
64 | }; | |
65 | static struct list_head nfsd_list = LIST_HEAD_INIT(nfsd_list); | |
66 | ||
3fb803a9 AG |
67 | #if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) |
68 | static struct svc_stat nfsd_acl_svcstats; | |
69 | static struct svc_version * nfsd_acl_version[] = { | |
70 | [2] = &nfsd_acl_version2, | |
71 | [3] = &nfsd_acl_version3, | |
72 | }; | |
73 | ||
74 | #define NFSD_ACL_MINVERS 2 | |
75 | #define NFSD_ACL_NRVERS (sizeof(nfsd_acl_version)/sizeof(nfsd_acl_version[0])) | |
76 | static struct svc_version *nfsd_acl_versions[NFSD_ACL_NRVERS]; | |
77 | ||
78 | static struct svc_program nfsd_acl_program = { | |
79 | .pg_prog = NFS_ACL_PROGRAM, | |
80 | .pg_nvers = NFSD_ACL_NRVERS, | |
81 | .pg_vers = nfsd_acl_versions, | |
82 | .pg_name = "nfsd", | |
83 | .pg_class = "nfsd", | |
84 | .pg_stats = &nfsd_acl_svcstats, | |
85 | .pg_authenticate = &svc_set_client, | |
86 | }; | |
87 | ||
88 | static struct svc_stat nfsd_acl_svcstats = { | |
89 | .program = &nfsd_acl_program, | |
90 | }; | |
91 | #endif /* defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) */ | |
92 | ||
70c3b76c N |
93 | static struct svc_version * nfsd_version[] = { |
94 | [2] = &nfsd_version2, | |
95 | #if defined(CONFIG_NFSD_V3) | |
96 | [3] = &nfsd_version3, | |
97 | #endif | |
98 | #if defined(CONFIG_NFSD_V4) | |
99 | [4] = &nfsd_version4, | |
100 | #endif | |
101 | }; | |
102 | ||
103 | #define NFSD_MINVERS 2 | |
104 | #define NFSD_NRVERS (sizeof(nfsd_version)/sizeof(nfsd_version[0])) | |
105 | static struct svc_version *nfsd_versions[NFSD_NRVERS]; | |
106 | ||
107 | struct svc_program nfsd_program = { | |
3fb803a9 AG |
108 | #if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) |
109 | .pg_next = &nfsd_acl_program, | |
110 | #endif | |
70c3b76c N |
111 | .pg_prog = NFS_PROGRAM, /* program number */ |
112 | .pg_nvers = NFSD_NRVERS, /* nr of entries in nfsd_version */ | |
113 | .pg_vers = nfsd_versions, /* version table */ | |
114 | .pg_name = "nfsd", /* program name */ | |
115 | .pg_class = "nfsd", /* authentication class */ | |
116 | .pg_stats = &nfsd_svcstats, /* version table */ | |
117 | .pg_authenticate = &svc_set_client, /* export authentication */ | |
118 | ||
119 | }; | |
120 | ||
1da177e4 LT |
121 | /* |
122 | * Maximum number of nfsd processes | |
123 | */ | |
124 | #define NFSD_MAXSERVS 8192 | |
125 | ||
126 | int nfsd_nrthreads(void) | |
127 | { | |
128 | if (nfsd_serv == NULL) | |
129 | return 0; | |
130 | else | |
131 | return nfsd_serv->sv_nrthreads; | |
132 | } | |
133 | ||
134 | int | |
135 | nfsd_svc(unsigned short port, int nrservs) | |
136 | { | |
137 | int error; | |
70c3b76c | 138 | int none_left, found_one, i; |
1da177e4 LT |
139 | struct list_head *victim; |
140 | ||
141 | lock_kernel(); | |
70c3b76c N |
142 | dprintk("nfsd: creating service: vers 0x%x\n", |
143 | nfsd_versbits); | |
1da177e4 LT |
144 | error = -EINVAL; |
145 | if (nrservs <= 0) | |
146 | nrservs = 0; | |
147 | if (nrservs > NFSD_MAXSERVS) | |
148 | nrservs = NFSD_MAXSERVS; | |
149 | ||
150 | /* Readahead param cache - will no-op if it already exists */ | |
151 | error = nfsd_racache_init(2*nrservs); | |
152 | if (error<0) | |
153 | goto out; | |
76a3550e | 154 | error = nfs4_state_start(); |
1da177e4 LT |
155 | if (error<0) |
156 | goto out; | |
157 | if (!nfsd_serv) { | |
70c3b76c N |
158 | /* |
159 | * Use the nfsd_ctlbits to define which | |
160 | * versions that will be advertised. | |
161 | * If nfsd_ctlbits doesn't list any version, | |
162 | * export them all. | |
163 | */ | |
164 | found_one = 0; | |
165 | ||
166 | for (i = NFSD_MINVERS; i < NFSD_NRVERS; i++) { | |
167 | if (NFSCTL_VERISSET(nfsd_versbits, i)) { | |
168 | nfsd_program.pg_vers[i] = nfsd_version[i]; | |
169 | found_one = 1; | |
170 | } else | |
171 | nfsd_program.pg_vers[i] = NULL; | |
172 | } | |
173 | ||
174 | if (!found_one) { | |
175 | for (i = NFSD_MINVERS; i < NFSD_NRVERS; i++) | |
176 | nfsd_program.pg_vers[i] = nfsd_version[i]; | |
177 | } | |
178 | ||
3fb803a9 AG |
179 | |
180 | #if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) | |
181 | found_one = 0; | |
182 | ||
183 | for (i = NFSD_ACL_MINVERS; i < NFSD_ACL_NRVERS; i++) { | |
184 | if (NFSCTL_VERISSET(nfsd_versbits, i)) { | |
185 | nfsd_acl_program.pg_vers[i] = | |
186 | nfsd_acl_version[i]; | |
187 | found_one = 1; | |
188 | } else | |
189 | nfsd_acl_program.pg_vers[i] = NULL; | |
190 | } | |
191 | ||
192 | if (!found_one) { | |
193 | for (i = NFSD_ACL_MINVERS; i < NFSD_ACL_NRVERS; i++) | |
194 | nfsd_acl_program.pg_vers[i] = | |
195 | nfsd_acl_version[i]; | |
196 | } | |
197 | #endif | |
198 | ||
1da177e4 LT |
199 | atomic_set(&nfsd_busy, 0); |
200 | error = -ENOMEM; | |
201 | nfsd_serv = svc_create(&nfsd_program, NFSD_BUFSIZE); | |
202 | if (nfsd_serv == NULL) | |
203 | goto out; | |
204 | error = svc_makesock(nfsd_serv, IPPROTO_UDP, port); | |
205 | if (error < 0) | |
206 | goto failure; | |
207 | ||
208 | #ifdef CONFIG_NFSD_TCP | |
209 | error = svc_makesock(nfsd_serv, IPPROTO_TCP, port); | |
210 | if (error < 0) | |
211 | goto failure; | |
212 | #endif | |
213 | do_gettimeofday(&nfssvc_boot); /* record boot time */ | |
214 | } else | |
215 | nfsd_serv->sv_nrthreads++; | |
216 | nrservs -= (nfsd_serv->sv_nrthreads-1); | |
217 | while (nrservs > 0) { | |
218 | nrservs--; | |
219 | __module_get(THIS_MODULE); | |
220 | error = svc_create_thread(nfsd, nfsd_serv); | |
221 | if (error < 0) { | |
222 | module_put(THIS_MODULE); | |
223 | break; | |
224 | } | |
225 | } | |
226 | victim = nfsd_list.next; | |
227 | while (nrservs < 0 && victim != &nfsd_list) { | |
228 | struct nfsd_list *nl = | |
229 | list_entry(victim,struct nfsd_list, list); | |
230 | victim = victim->next; | |
231 | send_sig(SIG_NOCLEAN, nl->task, 1); | |
232 | nrservs++; | |
233 | } | |
234 | failure: | |
235 | none_left = (nfsd_serv->sv_nrthreads == 1); | |
236 | svc_destroy(nfsd_serv); /* Release server */ | |
237 | if (none_left) { | |
238 | nfsd_serv = NULL; | |
239 | nfsd_racache_shutdown(); | |
240 | nfs4_state_shutdown(); | |
241 | } | |
242 | out: | |
243 | unlock_kernel(); | |
244 | return error; | |
245 | } | |
246 | ||
247 | static inline void | |
248 | update_thread_usage(int busy_threads) | |
249 | { | |
250 | unsigned long prev_call; | |
251 | unsigned long diff; | |
252 | int decile; | |
253 | ||
254 | spin_lock(&nfsd_call_lock); | |
255 | prev_call = nfsd_last_call; | |
256 | nfsd_last_call = jiffies; | |
257 | decile = busy_threads*10/nfsdstats.th_cnt; | |
258 | if (decile>0 && decile <= 10) { | |
259 | diff = nfsd_last_call - prev_call; | |
260 | if ( (nfsdstats.th_usage[decile-1] += diff) >= NFSD_USAGE_WRAP) | |
261 | nfsdstats.th_usage[decile-1] -= NFSD_USAGE_WRAP; | |
262 | if (decile == 10) | |
263 | nfsdstats.th_fullcnt++; | |
264 | } | |
265 | spin_unlock(&nfsd_call_lock); | |
266 | } | |
267 | ||
268 | /* | |
269 | * This is the NFS server kernel thread | |
270 | */ | |
271 | static void | |
272 | nfsd(struct svc_rqst *rqstp) | |
273 | { | |
274 | struct svc_serv *serv = rqstp->rq_server; | |
275 | struct fs_struct *fsp; | |
276 | int err; | |
277 | struct nfsd_list me; | |
278 | sigset_t shutdown_mask, allowed_mask; | |
279 | ||
280 | /* Lock module and set up kernel thread */ | |
281 | lock_kernel(); | |
282 | daemonize("nfsd"); | |
283 | ||
284 | /* After daemonize() this kernel thread shares current->fs | |
285 | * with the init process. We need to create files with a | |
286 | * umask of 0 instead of init's umask. */ | |
287 | fsp = copy_fs_struct(current->fs); | |
288 | if (!fsp) { | |
289 | printk("Unable to start nfsd thread: out of memory\n"); | |
290 | goto out; | |
291 | } | |
292 | exit_fs(current); | |
293 | current->fs = fsp; | |
294 | current->fs->umask = 0; | |
295 | ||
296 | siginitsetinv(&shutdown_mask, SHUTDOWN_SIGS); | |
297 | siginitsetinv(&allowed_mask, ALLOWED_SIGS); | |
298 | ||
299 | nfsdstats.th_cnt++; | |
300 | ||
301 | lockd_up(); /* start lockd */ | |
302 | ||
303 | me.task = current; | |
304 | list_add(&me.list, &nfsd_list); | |
305 | ||
306 | unlock_kernel(); | |
307 | ||
308 | /* | |
309 | * We want less throttling in balance_dirty_pages() so that nfs to | |
310 | * localhost doesn't cause nfsd to lock up due to all the client's | |
311 | * dirty pages. | |
312 | */ | |
313 | current->flags |= PF_LESS_THROTTLE; | |
314 | ||
315 | /* | |
316 | * The main request loop | |
317 | */ | |
318 | for (;;) { | |
319 | /* Block all but the shutdown signals */ | |
320 | sigprocmask(SIG_SETMASK, &shutdown_mask, NULL); | |
321 | ||
322 | /* | |
323 | * Find a socket with data available and call its | |
324 | * recvfrom routine. | |
325 | */ | |
326 | while ((err = svc_recv(serv, rqstp, | |
327 | 60*60*HZ)) == -EAGAIN) | |
328 | ; | |
329 | if (err < 0) | |
330 | break; | |
331 | update_thread_usage(atomic_read(&nfsd_busy)); | |
332 | atomic_inc(&nfsd_busy); | |
333 | ||
334 | /* Lock the export hash tables for reading. */ | |
335 | exp_readlock(); | |
336 | ||
337 | /* Process request with signals blocked. */ | |
338 | sigprocmask(SIG_SETMASK, &allowed_mask, NULL); | |
339 | ||
340 | svc_process(serv, rqstp); | |
341 | ||
342 | /* Unlock export hash tables */ | |
343 | exp_readunlock(); | |
344 | update_thread_usage(atomic_read(&nfsd_busy)); | |
345 | atomic_dec(&nfsd_busy); | |
346 | } | |
347 | ||
348 | if (err != -EINTR) { | |
349 | printk(KERN_WARNING "nfsd: terminating on error %d\n", -err); | |
350 | } else { | |
351 | unsigned int signo; | |
352 | ||
353 | for (signo = 1; signo <= _NSIG; signo++) | |
354 | if (sigismember(¤t->pending.signal, signo) && | |
355 | !sigismember(¤t->blocked, signo)) | |
356 | break; | |
357 | err = signo; | |
358 | } | |
9e416052 N |
359 | /* Clear signals before calling lockd_down() and svc_exit_thread() */ |
360 | flush_signals(current); | |
1da177e4 LT |
361 | |
362 | lock_kernel(); | |
363 | ||
364 | /* Release lockd */ | |
365 | lockd_down(); | |
366 | ||
367 | /* Check if this is last thread */ | |
368 | if (serv->sv_nrthreads==1) { | |
369 | ||
370 | printk(KERN_WARNING "nfsd: last server has exited\n"); | |
371 | if (err != SIG_NOCLEAN) { | |
372 | printk(KERN_WARNING "nfsd: unexporting all filesystems\n"); | |
373 | nfsd_export_flush(); | |
374 | } | |
375 | nfsd_serv = NULL; | |
376 | nfsd_racache_shutdown(); /* release read-ahead cache */ | |
377 | nfs4_state_shutdown(); | |
378 | } | |
379 | list_del(&me.list); | |
380 | nfsdstats.th_cnt --; | |
381 | ||
382 | out: | |
383 | /* Release the thread */ | |
384 | svc_exit_thread(rqstp); | |
385 | ||
386 | /* Release module */ | |
c4f92dba | 387 | unlock_kernel(); |
1da177e4 LT |
388 | module_put_and_exit(0); |
389 | } | |
390 | ||
391 | int | |
392 | nfsd_dispatch(struct svc_rqst *rqstp, u32 *statp) | |
393 | { | |
394 | struct svc_procedure *proc; | |
395 | kxdrproc_t xdr; | |
396 | u32 nfserr; | |
397 | u32 *nfserrp; | |
398 | ||
399 | dprintk("nfsd_dispatch: vers %d proc %d\n", | |
400 | rqstp->rq_vers, rqstp->rq_proc); | |
401 | proc = rqstp->rq_procinfo; | |
402 | ||
403 | /* Check whether we have this call in the cache. */ | |
404 | switch (nfsd_cache_lookup(rqstp, proc->pc_cachetype)) { | |
405 | case RC_INTR: | |
406 | case RC_DROPIT: | |
407 | return 0; | |
408 | case RC_REPLY: | |
409 | return 1; | |
410 | case RC_DOIT:; | |
411 | /* do it */ | |
412 | } | |
413 | ||
414 | /* Decode arguments */ | |
415 | xdr = proc->pc_decode; | |
416 | if (xdr && !xdr(rqstp, (u32*)rqstp->rq_arg.head[0].iov_base, | |
417 | rqstp->rq_argp)) { | |
418 | dprintk("nfsd: failed to decode arguments!\n"); | |
419 | nfsd_cache_update(rqstp, RC_NOCACHE, NULL); | |
420 | *statp = rpc_garbage_args; | |
421 | return 1; | |
422 | } | |
423 | ||
424 | /* need to grab the location to store the status, as | |
425 | * nfsv4 does some encoding while processing | |
426 | */ | |
427 | nfserrp = rqstp->rq_res.head[0].iov_base | |
428 | + rqstp->rq_res.head[0].iov_len; | |
429 | rqstp->rq_res.head[0].iov_len += sizeof(u32); | |
430 | ||
431 | /* Now call the procedure handler, and encode NFS status. */ | |
432 | nfserr = proc->pc_func(rqstp, rqstp->rq_argp, rqstp->rq_resp); | |
433 | if (nfserr == nfserr_jukebox && rqstp->rq_vers == 2) | |
434 | nfserr = nfserr_dropit; | |
435 | if (nfserr == nfserr_dropit) { | |
436 | dprintk("nfsd: Dropping request due to malloc failure!\n"); | |
437 | nfsd_cache_update(rqstp, RC_NOCACHE, NULL); | |
438 | return 0; | |
439 | } | |
440 | ||
441 | if (rqstp->rq_proc != 0) | |
442 | *nfserrp++ = nfserr; | |
443 | ||
444 | /* Encode result. | |
445 | * For NFSv2, additional info is never returned in case of an error. | |
446 | */ | |
447 | if (!(nfserr && rqstp->rq_vers == 2)) { | |
448 | xdr = proc->pc_encode; | |
449 | if (xdr && !xdr(rqstp, nfserrp, | |
450 | rqstp->rq_resp)) { | |
451 | /* Failed to encode result. Release cache entry */ | |
452 | dprintk("nfsd: failed to encode result!\n"); | |
453 | nfsd_cache_update(rqstp, RC_NOCACHE, NULL); | |
454 | *statp = rpc_system_err; | |
455 | return 1; | |
456 | } | |
457 | } | |
458 | ||
459 | /* Store reply in cache. */ | |
460 | nfsd_cache_update(rqstp, proc->pc_cachetype, statp + 1); | |
461 | return 1; | |
462 | } |