Commit | Line | Data |
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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 | ||
1da177e4 LT |
11 | #include <linux/module.h> |
12 | ||
13 | #include <linux/time.h> | |
14 | #include <linux/errno.h> | |
15 | #include <linux/nfs.h> | |
16 | #include <linux/in.h> | |
17 | #include <linux/uio.h> | |
18 | #include <linux/unistd.h> | |
19 | #include <linux/slab.h> | |
20 | #include <linux/smp.h> | |
21 | #include <linux/smp_lock.h> | |
22 | #include <linux/fs_struct.h> | |
23 | ||
24 | #include <linux/sunrpc/types.h> | |
25 | #include <linux/sunrpc/stats.h> | |
26 | #include <linux/sunrpc/svc.h> | |
27 | #include <linux/sunrpc/svcsock.h> | |
28 | #include <linux/sunrpc/cache.h> | |
29 | #include <linux/nfsd/nfsd.h> | |
30 | #include <linux/nfsd/stats.h> | |
31 | #include <linux/nfsd/cache.h> | |
70c3b76c | 32 | #include <linux/nfsd/syscall.h> |
1da177e4 | 33 | #include <linux/lockd/bind.h> |
a257cdd0 | 34 | #include <linux/nfsacl.h> |
1da177e4 LT |
35 | |
36 | #define NFSDDBG_FACILITY NFSDDBG_SVC | |
37 | ||
38 | /* these signals will be delivered to an nfsd thread | |
39 | * when handling a request | |
40 | */ | |
41 | #define ALLOWED_SIGS (sigmask(SIGKILL)) | |
42 | /* these signals will be delivered to an nfsd thread | |
43 | * when not handling a request. i.e. when waiting | |
44 | */ | |
45 | #define SHUTDOWN_SIGS (sigmask(SIGKILL) | sigmask(SIGHUP) | sigmask(SIGINT) | sigmask(SIGQUIT)) | |
46 | /* if the last thread dies with SIGHUP, then the exports table is | |
47 | * left unchanged ( like 2.4-{0-9} ). Any other signal will clear | |
48 | * the exports table (like 2.2). | |
49 | */ | |
50 | #define SIG_NOCLEAN SIGHUP | |
51 | ||
52 | extern struct svc_program nfsd_program; | |
53 | static void nfsd(struct svc_rqst *rqstp); | |
54 | struct timeval nfssvc_boot; | |
70c3b76c | 55 | struct svc_serv *nfsd_serv; |
1da177e4 LT |
56 | static atomic_t nfsd_busy; |
57 | static unsigned long nfsd_last_call; | |
58 | static DEFINE_SPINLOCK(nfsd_call_lock); | |
59 | ||
60 | struct nfsd_list { | |
61 | struct list_head list; | |
62 | struct task_struct *task; | |
63 | }; | |
64 | static struct list_head nfsd_list = LIST_HEAD_INIT(nfsd_list); | |
65 | ||
3fb803a9 AG |
66 | #if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) |
67 | static struct svc_stat nfsd_acl_svcstats; | |
68 | static struct svc_version * nfsd_acl_version[] = { | |
69 | [2] = &nfsd_acl_version2, | |
70 | [3] = &nfsd_acl_version3, | |
71 | }; | |
72 | ||
73 | #define NFSD_ACL_MINVERS 2 | |
e8c96f8c | 74 | #define NFSD_ACL_NRVERS ARRAY_SIZE(nfsd_acl_version) |
3fb803a9 AG |
75 | static struct svc_version *nfsd_acl_versions[NFSD_ACL_NRVERS]; |
76 | ||
77 | static struct svc_program nfsd_acl_program = { | |
78 | .pg_prog = NFS_ACL_PROGRAM, | |
79 | .pg_nvers = NFSD_ACL_NRVERS, | |
80 | .pg_vers = nfsd_acl_versions, | |
81 | .pg_name = "nfsd", | |
82 | .pg_class = "nfsd", | |
83 | .pg_stats = &nfsd_acl_svcstats, | |
84 | .pg_authenticate = &svc_set_client, | |
85 | }; | |
86 | ||
87 | static struct svc_stat nfsd_acl_svcstats = { | |
88 | .program = &nfsd_acl_program, | |
89 | }; | |
90 | #endif /* defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) */ | |
91 | ||
70c3b76c N |
92 | static struct svc_version * nfsd_version[] = { |
93 | [2] = &nfsd_version2, | |
94 | #if defined(CONFIG_NFSD_V3) | |
95 | [3] = &nfsd_version3, | |
96 | #endif | |
97 | #if defined(CONFIG_NFSD_V4) | |
98 | [4] = &nfsd_version4, | |
99 | #endif | |
100 | }; | |
101 | ||
102 | #define NFSD_MINVERS 2 | |
e8c96f8c | 103 | #define NFSD_NRVERS ARRAY_SIZE(nfsd_version) |
70c3b76c N |
104 | static struct svc_version *nfsd_versions[NFSD_NRVERS]; |
105 | ||
106 | struct svc_program nfsd_program = { | |
3fb803a9 AG |
107 | #if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) |
108 | .pg_next = &nfsd_acl_program, | |
109 | #endif | |
70c3b76c N |
110 | .pg_prog = NFS_PROGRAM, /* program number */ |
111 | .pg_nvers = NFSD_NRVERS, /* nr of entries in nfsd_version */ | |
112 | .pg_vers = nfsd_versions, /* version table */ | |
113 | .pg_name = "nfsd", /* program name */ | |
114 | .pg_class = "nfsd", /* authentication class */ | |
115 | .pg_stats = &nfsd_svcstats, /* version table */ | |
116 | .pg_authenticate = &svc_set_client, /* export authentication */ | |
117 | ||
118 | }; | |
119 | ||
1da177e4 LT |
120 | /* |
121 | * Maximum number of nfsd processes | |
122 | */ | |
123 | #define NFSD_MAXSERVS 8192 | |
124 | ||
125 | int nfsd_nrthreads(void) | |
126 | { | |
127 | if (nfsd_serv == NULL) | |
128 | return 0; | |
129 | else | |
130 | return nfsd_serv->sv_nrthreads; | |
131 | } | |
132 | ||
133 | int | |
134 | nfsd_svc(unsigned short port, int nrservs) | |
135 | { | |
136 | int error; | |
70c3b76c | 137 | int none_left, found_one, i; |
1da177e4 LT |
138 | struct list_head *victim; |
139 | ||
140 | lock_kernel(); | |
70c3b76c N |
141 | dprintk("nfsd: creating service: vers 0x%x\n", |
142 | nfsd_versbits); | |
1da177e4 LT |
143 | error = -EINVAL; |
144 | if (nrservs <= 0) | |
145 | nrservs = 0; | |
146 | if (nrservs > NFSD_MAXSERVS) | |
147 | nrservs = NFSD_MAXSERVS; | |
148 | ||
149 | /* Readahead param cache - will no-op if it already exists */ | |
150 | error = nfsd_racache_init(2*nrservs); | |
151 | if (error<0) | |
152 | goto out; | |
76a3550e | 153 | error = nfs4_state_start(); |
1da177e4 LT |
154 | if (error<0) |
155 | goto out; | |
156 | if (!nfsd_serv) { | |
70c3b76c N |
157 | /* |
158 | * Use the nfsd_ctlbits to define which | |
159 | * versions that will be advertised. | |
160 | * If nfsd_ctlbits doesn't list any version, | |
161 | * export them all. | |
162 | */ | |
163 | found_one = 0; | |
164 | ||
165 | for (i = NFSD_MINVERS; i < NFSD_NRVERS; i++) { | |
166 | if (NFSCTL_VERISSET(nfsd_versbits, i)) { | |
167 | nfsd_program.pg_vers[i] = nfsd_version[i]; | |
168 | found_one = 1; | |
169 | } else | |
170 | nfsd_program.pg_vers[i] = NULL; | |
171 | } | |
172 | ||
173 | if (!found_one) { | |
174 | for (i = NFSD_MINVERS; i < NFSD_NRVERS; i++) | |
175 | nfsd_program.pg_vers[i] = nfsd_version[i]; | |
176 | } | |
177 | ||
3fb803a9 AG |
178 | |
179 | #if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) | |
180 | found_one = 0; | |
181 | ||
182 | for (i = NFSD_ACL_MINVERS; i < NFSD_ACL_NRVERS; i++) { | |
183 | if (NFSCTL_VERISSET(nfsd_versbits, i)) { | |
184 | nfsd_acl_program.pg_vers[i] = | |
185 | nfsd_acl_version[i]; | |
186 | found_one = 1; | |
187 | } else | |
188 | nfsd_acl_program.pg_vers[i] = NULL; | |
189 | } | |
190 | ||
191 | if (!found_one) { | |
192 | for (i = NFSD_ACL_MINVERS; i < NFSD_ACL_NRVERS; i++) | |
193 | nfsd_acl_program.pg_vers[i] = | |
194 | nfsd_acl_version[i]; | |
195 | } | |
196 | #endif | |
197 | ||
1da177e4 LT |
198 | atomic_set(&nfsd_busy, 0); |
199 | error = -ENOMEM; | |
200 | nfsd_serv = svc_create(&nfsd_program, NFSD_BUFSIZE); | |
201 | if (nfsd_serv == NULL) | |
202 | goto out; | |
203 | error = svc_makesock(nfsd_serv, IPPROTO_UDP, port); | |
204 | if (error < 0) | |
205 | goto failure; | |
206 | ||
207 | #ifdef CONFIG_NFSD_TCP | |
208 | error = svc_makesock(nfsd_serv, IPPROTO_TCP, port); | |
209 | if (error < 0) | |
210 | goto failure; | |
211 | #endif | |
212 | do_gettimeofday(&nfssvc_boot); /* record boot time */ | |
213 | } else | |
214 | nfsd_serv->sv_nrthreads++; | |
215 | nrservs -= (nfsd_serv->sv_nrthreads-1); | |
216 | while (nrservs > 0) { | |
217 | nrservs--; | |
218 | __module_get(THIS_MODULE); | |
219 | error = svc_create_thread(nfsd, nfsd_serv); | |
220 | if (error < 0) { | |
221 | module_put(THIS_MODULE); | |
222 | break; | |
223 | } | |
224 | } | |
225 | victim = nfsd_list.next; | |
226 | while (nrservs < 0 && victim != &nfsd_list) { | |
227 | struct nfsd_list *nl = | |
228 | list_entry(victim,struct nfsd_list, list); | |
229 | victim = victim->next; | |
230 | send_sig(SIG_NOCLEAN, nl->task, 1); | |
231 | nrservs++; | |
232 | } | |
233 | failure: | |
234 | none_left = (nfsd_serv->sv_nrthreads == 1); | |
235 | svc_destroy(nfsd_serv); /* Release server */ | |
236 | if (none_left) { | |
237 | nfsd_serv = NULL; | |
238 | nfsd_racache_shutdown(); | |
239 | nfs4_state_shutdown(); | |
240 | } | |
241 | out: | |
242 | unlock_kernel(); | |
243 | return error; | |
244 | } | |
245 | ||
246 | static inline void | |
247 | update_thread_usage(int busy_threads) | |
248 | { | |
249 | unsigned long prev_call; | |
250 | unsigned long diff; | |
251 | int decile; | |
252 | ||
253 | spin_lock(&nfsd_call_lock); | |
254 | prev_call = nfsd_last_call; | |
255 | nfsd_last_call = jiffies; | |
256 | decile = busy_threads*10/nfsdstats.th_cnt; | |
257 | if (decile>0 && decile <= 10) { | |
258 | diff = nfsd_last_call - prev_call; | |
259 | if ( (nfsdstats.th_usage[decile-1] += diff) >= NFSD_USAGE_WRAP) | |
260 | nfsdstats.th_usage[decile-1] -= NFSD_USAGE_WRAP; | |
261 | if (decile == 10) | |
262 | nfsdstats.th_fullcnt++; | |
263 | } | |
264 | spin_unlock(&nfsd_call_lock); | |
265 | } | |
266 | ||
267 | /* | |
268 | * This is the NFS server kernel thread | |
269 | */ | |
270 | static void | |
271 | nfsd(struct svc_rqst *rqstp) | |
272 | { | |
273 | struct svc_serv *serv = rqstp->rq_server; | |
274 | struct fs_struct *fsp; | |
275 | int err; | |
276 | struct nfsd_list me; | |
277 | sigset_t shutdown_mask, allowed_mask; | |
278 | ||
279 | /* Lock module and set up kernel thread */ | |
280 | lock_kernel(); | |
281 | daemonize("nfsd"); | |
282 | ||
283 | /* After daemonize() this kernel thread shares current->fs | |
284 | * with the init process. We need to create files with a | |
285 | * umask of 0 instead of init's umask. */ | |
286 | fsp = copy_fs_struct(current->fs); | |
287 | if (!fsp) { | |
288 | printk("Unable to start nfsd thread: out of memory\n"); | |
289 | goto out; | |
290 | } | |
291 | exit_fs(current); | |
292 | current->fs = fsp; | |
293 | current->fs->umask = 0; | |
294 | ||
295 | siginitsetinv(&shutdown_mask, SHUTDOWN_SIGS); | |
296 | siginitsetinv(&allowed_mask, ALLOWED_SIGS); | |
297 | ||
298 | nfsdstats.th_cnt++; | |
299 | ||
300 | lockd_up(); /* start lockd */ | |
301 | ||
302 | me.task = current; | |
303 | list_add(&me.list, &nfsd_list); | |
304 | ||
305 | unlock_kernel(); | |
306 | ||
307 | /* | |
308 | * We want less throttling in balance_dirty_pages() so that nfs to | |
309 | * localhost doesn't cause nfsd to lock up due to all the client's | |
310 | * dirty pages. | |
311 | */ | |
312 | current->flags |= PF_LESS_THROTTLE; | |
313 | ||
314 | /* | |
315 | * The main request loop | |
316 | */ | |
317 | for (;;) { | |
318 | /* Block all but the shutdown signals */ | |
319 | sigprocmask(SIG_SETMASK, &shutdown_mask, NULL); | |
320 | ||
321 | /* | |
322 | * Find a socket with data available and call its | |
323 | * recvfrom routine. | |
324 | */ | |
325 | while ((err = svc_recv(serv, rqstp, | |
326 | 60*60*HZ)) == -EAGAIN) | |
327 | ; | |
328 | if (err < 0) | |
329 | break; | |
330 | update_thread_usage(atomic_read(&nfsd_busy)); | |
331 | atomic_inc(&nfsd_busy); | |
332 | ||
333 | /* Lock the export hash tables for reading. */ | |
334 | exp_readlock(); | |
335 | ||
336 | /* Process request with signals blocked. */ | |
337 | sigprocmask(SIG_SETMASK, &allowed_mask, NULL); | |
338 | ||
339 | svc_process(serv, rqstp); | |
340 | ||
341 | /* Unlock export hash tables */ | |
342 | exp_readunlock(); | |
343 | update_thread_usage(atomic_read(&nfsd_busy)); | |
344 | atomic_dec(&nfsd_busy); | |
345 | } | |
346 | ||
347 | if (err != -EINTR) { | |
348 | printk(KERN_WARNING "nfsd: terminating on error %d\n", -err); | |
349 | } else { | |
350 | unsigned int signo; | |
351 | ||
352 | for (signo = 1; signo <= _NSIG; signo++) | |
353 | if (sigismember(¤t->pending.signal, signo) && | |
354 | !sigismember(¤t->blocked, signo)) | |
355 | break; | |
356 | err = signo; | |
357 | } | |
9e416052 N |
358 | /* Clear signals before calling lockd_down() and svc_exit_thread() */ |
359 | flush_signals(current); | |
1da177e4 LT |
360 | |
361 | lock_kernel(); | |
362 | ||
363 | /* Release lockd */ | |
364 | lockd_down(); | |
365 | ||
366 | /* Check if this is last thread */ | |
367 | if (serv->sv_nrthreads==1) { | |
368 | ||
369 | printk(KERN_WARNING "nfsd: last server has exited\n"); | |
370 | if (err != SIG_NOCLEAN) { | |
371 | printk(KERN_WARNING "nfsd: unexporting all filesystems\n"); | |
372 | nfsd_export_flush(); | |
373 | } | |
374 | nfsd_serv = NULL; | |
375 | nfsd_racache_shutdown(); /* release read-ahead cache */ | |
376 | nfs4_state_shutdown(); | |
377 | } | |
378 | list_del(&me.list); | |
379 | nfsdstats.th_cnt --; | |
380 | ||
381 | out: | |
382 | /* Release the thread */ | |
383 | svc_exit_thread(rqstp); | |
384 | ||
385 | /* Release module */ | |
c4f92dba | 386 | unlock_kernel(); |
1da177e4 LT |
387 | module_put_and_exit(0); |
388 | } | |
389 | ||
390 | int | |
391 | nfsd_dispatch(struct svc_rqst *rqstp, u32 *statp) | |
392 | { | |
393 | struct svc_procedure *proc; | |
394 | kxdrproc_t xdr; | |
395 | u32 nfserr; | |
396 | u32 *nfserrp; | |
397 | ||
398 | dprintk("nfsd_dispatch: vers %d proc %d\n", | |
399 | rqstp->rq_vers, rqstp->rq_proc); | |
400 | proc = rqstp->rq_procinfo; | |
401 | ||
402 | /* Check whether we have this call in the cache. */ | |
403 | switch (nfsd_cache_lookup(rqstp, proc->pc_cachetype)) { | |
404 | case RC_INTR: | |
405 | case RC_DROPIT: | |
406 | return 0; | |
407 | case RC_REPLY: | |
408 | return 1; | |
409 | case RC_DOIT:; | |
410 | /* do it */ | |
411 | } | |
412 | ||
413 | /* Decode arguments */ | |
414 | xdr = proc->pc_decode; | |
415 | if (xdr && !xdr(rqstp, (u32*)rqstp->rq_arg.head[0].iov_base, | |
416 | rqstp->rq_argp)) { | |
417 | dprintk("nfsd: failed to decode arguments!\n"); | |
418 | nfsd_cache_update(rqstp, RC_NOCACHE, NULL); | |
419 | *statp = rpc_garbage_args; | |
420 | return 1; | |
421 | } | |
422 | ||
423 | /* need to grab the location to store the status, as | |
424 | * nfsv4 does some encoding while processing | |
425 | */ | |
426 | nfserrp = rqstp->rq_res.head[0].iov_base | |
427 | + rqstp->rq_res.head[0].iov_len; | |
428 | rqstp->rq_res.head[0].iov_len += sizeof(u32); | |
429 | ||
430 | /* Now call the procedure handler, and encode NFS status. */ | |
431 | nfserr = proc->pc_func(rqstp, rqstp->rq_argp, rqstp->rq_resp); | |
432 | if (nfserr == nfserr_jukebox && rqstp->rq_vers == 2) | |
433 | nfserr = nfserr_dropit; | |
434 | if (nfserr == nfserr_dropit) { | |
435 | dprintk("nfsd: Dropping request due to malloc failure!\n"); | |
436 | nfsd_cache_update(rqstp, RC_NOCACHE, NULL); | |
437 | return 0; | |
438 | } | |
439 | ||
440 | if (rqstp->rq_proc != 0) | |
441 | *nfserrp++ = nfserr; | |
442 | ||
443 | /* Encode result. | |
444 | * For NFSv2, additional info is never returned in case of an error. | |
445 | */ | |
446 | if (!(nfserr && rqstp->rq_vers == 2)) { | |
447 | xdr = proc->pc_encode; | |
448 | if (xdr && !xdr(rqstp, nfserrp, | |
449 | rqstp->rq_resp)) { | |
450 | /* Failed to encode result. Release cache entry */ | |
451 | dprintk("nfsd: failed to encode result!\n"); | |
452 | nfsd_cache_update(rqstp, RC_NOCACHE, NULL); | |
453 | *statp = rpc_system_err; | |
454 | return 1; | |
455 | } | |
456 | } | |
457 | ||
458 | /* Store reply in cache. */ | |
459 | nfsd_cache_update(rqstp, proc->pc_cachetype, statp + 1); | |
460 | return 1; | |
461 | } |