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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 | ||
bc591ccf N |
133 | static int killsig; /* signal that was used to kill last nfsd */ |
134 | static void nfsd_last_thread(struct svc_serv *serv) | |
135 | { | |
136 | /* When last nfsd thread exits we need to do some clean-up */ | |
137 | nfsd_serv = NULL; | |
138 | nfsd_racache_shutdown(); | |
139 | nfs4_state_shutdown(); | |
140 | ||
141 | printk(KERN_WARNING "nfsd: last server has exited\n"); | |
142 | if (killsig != SIG_NOCLEAN) { | |
143 | printk(KERN_WARNING "nfsd: unexporting all filesystems\n"); | |
144 | nfsd_export_flush(); | |
145 | } | |
146 | } | |
1da177e4 LT |
147 | int |
148 | nfsd_svc(unsigned short port, int nrservs) | |
149 | { | |
150 | int error; | |
bc591ccf | 151 | int found_one, i; |
1da177e4 LT |
152 | struct list_head *victim; |
153 | ||
154 | lock_kernel(); | |
70c3b76c N |
155 | dprintk("nfsd: creating service: vers 0x%x\n", |
156 | nfsd_versbits); | |
1da177e4 LT |
157 | error = -EINVAL; |
158 | if (nrservs <= 0) | |
159 | nrservs = 0; | |
160 | if (nrservs > NFSD_MAXSERVS) | |
161 | nrservs = NFSD_MAXSERVS; | |
162 | ||
163 | /* Readahead param cache - will no-op if it already exists */ | |
164 | error = nfsd_racache_init(2*nrservs); | |
165 | if (error<0) | |
166 | goto out; | |
76a3550e | 167 | error = nfs4_state_start(); |
1da177e4 LT |
168 | if (error<0) |
169 | goto out; | |
170 | if (!nfsd_serv) { | |
70c3b76c N |
171 | /* |
172 | * Use the nfsd_ctlbits to define which | |
173 | * versions that will be advertised. | |
174 | * If nfsd_ctlbits doesn't list any version, | |
175 | * export them all. | |
176 | */ | |
177 | found_one = 0; | |
178 | ||
179 | for (i = NFSD_MINVERS; i < NFSD_NRVERS; i++) { | |
180 | if (NFSCTL_VERISSET(nfsd_versbits, i)) { | |
181 | nfsd_program.pg_vers[i] = nfsd_version[i]; | |
182 | found_one = 1; | |
183 | } else | |
184 | nfsd_program.pg_vers[i] = NULL; | |
185 | } | |
186 | ||
187 | if (!found_one) { | |
188 | for (i = NFSD_MINVERS; i < NFSD_NRVERS; i++) | |
189 | nfsd_program.pg_vers[i] = nfsd_version[i]; | |
190 | } | |
191 | ||
3fb803a9 AG |
192 | |
193 | #if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) | |
194 | found_one = 0; | |
195 | ||
196 | for (i = NFSD_ACL_MINVERS; i < NFSD_ACL_NRVERS; i++) { | |
197 | if (NFSCTL_VERISSET(nfsd_versbits, i)) { | |
198 | nfsd_acl_program.pg_vers[i] = | |
199 | nfsd_acl_version[i]; | |
200 | found_one = 1; | |
201 | } else | |
202 | nfsd_acl_program.pg_vers[i] = NULL; | |
203 | } | |
204 | ||
205 | if (!found_one) { | |
206 | for (i = NFSD_ACL_MINVERS; i < NFSD_ACL_NRVERS; i++) | |
207 | nfsd_acl_program.pg_vers[i] = | |
208 | nfsd_acl_version[i]; | |
209 | } | |
210 | #endif | |
211 | ||
1da177e4 LT |
212 | atomic_set(&nfsd_busy, 0); |
213 | error = -ENOMEM; | |
bc591ccf N |
214 | nfsd_serv = svc_create(&nfsd_program, NFSD_BUFSIZE, |
215 | nfsd_last_thread); | |
1da177e4 LT |
216 | if (nfsd_serv == NULL) |
217 | goto out; | |
218 | error = svc_makesock(nfsd_serv, IPPROTO_UDP, port); | |
219 | if (error < 0) | |
220 | goto failure; | |
221 | ||
222 | #ifdef CONFIG_NFSD_TCP | |
223 | error = svc_makesock(nfsd_serv, IPPROTO_TCP, port); | |
224 | if (error < 0) | |
225 | goto failure; | |
226 | #endif | |
227 | do_gettimeofday(&nfssvc_boot); /* record boot time */ | |
228 | } else | |
229 | nfsd_serv->sv_nrthreads++; | |
230 | nrservs -= (nfsd_serv->sv_nrthreads-1); | |
231 | while (nrservs > 0) { | |
232 | nrservs--; | |
233 | __module_get(THIS_MODULE); | |
234 | error = svc_create_thread(nfsd, nfsd_serv); | |
235 | if (error < 0) { | |
236 | module_put(THIS_MODULE); | |
237 | break; | |
238 | } | |
239 | } | |
240 | victim = nfsd_list.next; | |
241 | while (nrservs < 0 && victim != &nfsd_list) { | |
242 | struct nfsd_list *nl = | |
243 | list_entry(victim,struct nfsd_list, list); | |
244 | victim = victim->next; | |
245 | send_sig(SIG_NOCLEAN, nl->task, 1); | |
246 | nrservs++; | |
247 | } | |
248 | failure: | |
1da177e4 | 249 | svc_destroy(nfsd_serv); /* Release server */ |
1da177e4 LT |
250 | out: |
251 | unlock_kernel(); | |
252 | return error; | |
253 | } | |
254 | ||
255 | static inline void | |
256 | update_thread_usage(int busy_threads) | |
257 | { | |
258 | unsigned long prev_call; | |
259 | unsigned long diff; | |
260 | int decile; | |
261 | ||
262 | spin_lock(&nfsd_call_lock); | |
263 | prev_call = nfsd_last_call; | |
264 | nfsd_last_call = jiffies; | |
265 | decile = busy_threads*10/nfsdstats.th_cnt; | |
266 | if (decile>0 && decile <= 10) { | |
267 | diff = nfsd_last_call - prev_call; | |
268 | if ( (nfsdstats.th_usage[decile-1] += diff) >= NFSD_USAGE_WRAP) | |
269 | nfsdstats.th_usage[decile-1] -= NFSD_USAGE_WRAP; | |
270 | if (decile == 10) | |
271 | nfsdstats.th_fullcnt++; | |
272 | } | |
273 | spin_unlock(&nfsd_call_lock); | |
274 | } | |
275 | ||
276 | /* | |
277 | * This is the NFS server kernel thread | |
278 | */ | |
279 | static void | |
280 | nfsd(struct svc_rqst *rqstp) | |
281 | { | |
282 | struct svc_serv *serv = rqstp->rq_server; | |
283 | struct fs_struct *fsp; | |
284 | int err; | |
285 | struct nfsd_list me; | |
286 | sigset_t shutdown_mask, allowed_mask; | |
287 | ||
288 | /* Lock module and set up kernel thread */ | |
289 | lock_kernel(); | |
290 | daemonize("nfsd"); | |
291 | ||
292 | /* After daemonize() this kernel thread shares current->fs | |
293 | * with the init process. We need to create files with a | |
294 | * umask of 0 instead of init's umask. */ | |
295 | fsp = copy_fs_struct(current->fs); | |
296 | if (!fsp) { | |
297 | printk("Unable to start nfsd thread: out of memory\n"); | |
298 | goto out; | |
299 | } | |
300 | exit_fs(current); | |
301 | current->fs = fsp; | |
302 | current->fs->umask = 0; | |
303 | ||
304 | siginitsetinv(&shutdown_mask, SHUTDOWN_SIGS); | |
305 | siginitsetinv(&allowed_mask, ALLOWED_SIGS); | |
306 | ||
307 | nfsdstats.th_cnt++; | |
308 | ||
309 | lockd_up(); /* start lockd */ | |
310 | ||
311 | me.task = current; | |
312 | list_add(&me.list, &nfsd_list); | |
313 | ||
314 | unlock_kernel(); | |
315 | ||
316 | /* | |
317 | * We want less throttling in balance_dirty_pages() so that nfs to | |
318 | * localhost doesn't cause nfsd to lock up due to all the client's | |
319 | * dirty pages. | |
320 | */ | |
321 | current->flags |= PF_LESS_THROTTLE; | |
322 | ||
323 | /* | |
324 | * The main request loop | |
325 | */ | |
326 | for (;;) { | |
327 | /* Block all but the shutdown signals */ | |
328 | sigprocmask(SIG_SETMASK, &shutdown_mask, NULL); | |
329 | ||
330 | /* | |
331 | * Find a socket with data available and call its | |
332 | * recvfrom routine. | |
333 | */ | |
334 | while ((err = svc_recv(serv, rqstp, | |
335 | 60*60*HZ)) == -EAGAIN) | |
336 | ; | |
337 | if (err < 0) | |
338 | break; | |
339 | update_thread_usage(atomic_read(&nfsd_busy)); | |
340 | atomic_inc(&nfsd_busy); | |
341 | ||
342 | /* Lock the export hash tables for reading. */ | |
343 | exp_readlock(); | |
344 | ||
345 | /* Process request with signals blocked. */ | |
346 | sigprocmask(SIG_SETMASK, &allowed_mask, NULL); | |
347 | ||
348 | svc_process(serv, rqstp); | |
349 | ||
350 | /* Unlock export hash tables */ | |
351 | exp_readunlock(); | |
352 | update_thread_usage(atomic_read(&nfsd_busy)); | |
353 | atomic_dec(&nfsd_busy); | |
354 | } | |
355 | ||
356 | if (err != -EINTR) { | |
357 | printk(KERN_WARNING "nfsd: terminating on error %d\n", -err); | |
358 | } else { | |
359 | unsigned int signo; | |
360 | ||
361 | for (signo = 1; signo <= _NSIG; signo++) | |
362 | if (sigismember(¤t->pending.signal, signo) && | |
363 | !sigismember(¤t->blocked, signo)) | |
364 | break; | |
bc591ccf | 365 | killsig = signo; |
1da177e4 | 366 | } |
9e416052 N |
367 | /* Clear signals before calling lockd_down() and svc_exit_thread() */ |
368 | flush_signals(current); | |
1da177e4 LT |
369 | |
370 | lock_kernel(); | |
371 | ||
372 | /* Release lockd */ | |
373 | lockd_down(); | |
1da177e4 LT |
374 | list_del(&me.list); |
375 | nfsdstats.th_cnt --; | |
376 | ||
377 | out: | |
378 | /* Release the thread */ | |
379 | svc_exit_thread(rqstp); | |
380 | ||
381 | /* Release module */ | |
c4f92dba | 382 | unlock_kernel(); |
1da177e4 LT |
383 | module_put_and_exit(0); |
384 | } | |
385 | ||
386 | int | |
387 | nfsd_dispatch(struct svc_rqst *rqstp, u32 *statp) | |
388 | { | |
389 | struct svc_procedure *proc; | |
390 | kxdrproc_t xdr; | |
391 | u32 nfserr; | |
392 | u32 *nfserrp; | |
393 | ||
394 | dprintk("nfsd_dispatch: vers %d proc %d\n", | |
395 | rqstp->rq_vers, rqstp->rq_proc); | |
396 | proc = rqstp->rq_procinfo; | |
397 | ||
398 | /* Check whether we have this call in the cache. */ | |
399 | switch (nfsd_cache_lookup(rqstp, proc->pc_cachetype)) { | |
400 | case RC_INTR: | |
401 | case RC_DROPIT: | |
402 | return 0; | |
403 | case RC_REPLY: | |
404 | return 1; | |
405 | case RC_DOIT:; | |
406 | /* do it */ | |
407 | } | |
408 | ||
409 | /* Decode arguments */ | |
410 | xdr = proc->pc_decode; | |
411 | if (xdr && !xdr(rqstp, (u32*)rqstp->rq_arg.head[0].iov_base, | |
412 | rqstp->rq_argp)) { | |
413 | dprintk("nfsd: failed to decode arguments!\n"); | |
414 | nfsd_cache_update(rqstp, RC_NOCACHE, NULL); | |
415 | *statp = rpc_garbage_args; | |
416 | return 1; | |
417 | } | |
418 | ||
419 | /* need to grab the location to store the status, as | |
420 | * nfsv4 does some encoding while processing | |
421 | */ | |
422 | nfserrp = rqstp->rq_res.head[0].iov_base | |
423 | + rqstp->rq_res.head[0].iov_len; | |
424 | rqstp->rq_res.head[0].iov_len += sizeof(u32); | |
425 | ||
426 | /* Now call the procedure handler, and encode NFS status. */ | |
427 | nfserr = proc->pc_func(rqstp, rqstp->rq_argp, rqstp->rq_resp); | |
428 | if (nfserr == nfserr_jukebox && rqstp->rq_vers == 2) | |
429 | nfserr = nfserr_dropit; | |
430 | if (nfserr == nfserr_dropit) { | |
431 | dprintk("nfsd: Dropping request due to malloc failure!\n"); | |
432 | nfsd_cache_update(rqstp, RC_NOCACHE, NULL); | |
433 | return 0; | |
434 | } | |
435 | ||
436 | if (rqstp->rq_proc != 0) | |
437 | *nfserrp++ = nfserr; | |
438 | ||
439 | /* Encode result. | |
440 | * For NFSv2, additional info is never returned in case of an error. | |
441 | */ | |
442 | if (!(nfserr && rqstp->rq_vers == 2)) { | |
443 | xdr = proc->pc_encode; | |
444 | if (xdr && !xdr(rqstp, nfserrp, | |
445 | rqstp->rq_resp)) { | |
446 | /* Failed to encode result. Release cache entry */ | |
447 | dprintk("nfsd: failed to encode result!\n"); | |
448 | nfsd_cache_update(rqstp, RC_NOCACHE, NULL); | |
449 | *statp = rpc_system_err; | |
450 | return 1; | |
451 | } | |
452 | } | |
453 | ||
454 | /* Store reply in cache. */ | |
455 | nfsd_cache_update(rqstp, proc->pc_cachetype, statp + 1); | |
456 | return 1; | |
457 | } |