2 * linux/fs/nfsd/nfssvc.c
4 * Central processing for nfsd.
6 * Authors: Olaf Kirch (okir@monad.swb.de)
8 * Copyright (C) 1995, 1996, 1997 Olaf Kirch <okir@monad.swb.de>
11 #include <linux/config.h>
12 #include <linux/module.h>
14 #include <linux/time.h>
15 #include <linux/errno.h>
16 #include <linux/nfs.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>
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>
33 #include <linux/lockd/bind.h>
35 #define NFSDDBG_FACILITY NFSDDBG_SVC
37 /* these signals will be delivered to an nfsd thread
38 * when handling a request
40 #define ALLOWED_SIGS (sigmask(SIGKILL))
41 /* these signals will be delivered to an nfsd thread
42 * when not handling a request. i.e. when waiting
44 #define SHUTDOWN_SIGS (sigmask(SIGKILL) | sigmask(SIGHUP) | sigmask(SIGINT) | sigmask(SIGQUIT))
45 /* if the last thread dies with SIGHUP, then the exports table is
46 * left unchanged ( like 2.4-{0-9} ). Any other signal will clear
47 * the exports table (like 2.2).
49 #define SIG_NOCLEAN SIGHUP
51 extern struct svc_program nfsd_program
;
52 static void nfsd(struct svc_rqst
*rqstp
);
53 struct timeval nfssvc_boot
;
54 static struct svc_serv
*nfsd_serv
;
55 static atomic_t nfsd_busy
;
56 static unsigned long nfsd_last_call
;
57 static spinlock_t nfsd_call_lock
= SPIN_LOCK_UNLOCKED
;
60 struct list_head list
;
61 struct task_struct
*task
;
63 struct list_head nfsd_list
= LIST_HEAD_INIT(nfsd_list
);
66 * Maximum number of nfsd processes
68 #define NFSD_MAXSERVS 8192
70 int nfsd_nrthreads(void)
72 if (nfsd_serv
== NULL
)
75 return nfsd_serv
->sv_nrthreads
;
79 nfsd_svc(unsigned short port
, int nrservs
)
83 struct list_head
*victim
;
86 dprintk("nfsd: creating service\n");
90 if (nrservs
> NFSD_MAXSERVS
)
91 nrservs
= NFSD_MAXSERVS
;
93 /* Readahead param cache - will no-op if it already exists */
94 error
= nfsd_racache_init(2*nrservs
);
99 atomic_set(&nfsd_busy
, 0);
101 nfsd_serv
= svc_create(&nfsd_program
, NFSD_BUFSIZE
);
102 if (nfsd_serv
== NULL
)
104 error
= svc_makesock(nfsd_serv
, IPPROTO_UDP
, port
);
108 #ifdef CONFIG_NFSD_TCP
109 error
= svc_makesock(nfsd_serv
, IPPROTO_TCP
, port
);
113 do_gettimeofday(&nfssvc_boot
); /* record boot time */
115 nfsd_serv
->sv_nrthreads
++;
116 nrservs
-= (nfsd_serv
->sv_nrthreads
-1);
117 while (nrservs
> 0) {
119 __module_get(THIS_MODULE
);
120 error
= svc_create_thread(nfsd
, nfsd_serv
);
122 module_put(THIS_MODULE
);
126 victim
= nfsd_list
.next
;
127 while (nrservs
< 0 && victim
!= &nfsd_list
) {
128 struct nfsd_list
*nl
=
129 list_entry(victim
,struct nfsd_list
, list
);
130 victim
= victim
->next
;
131 send_sig(SIG_NOCLEAN
, nl
->task
, 1);
135 none_left
= (nfsd_serv
->sv_nrthreads
== 1);
136 svc_destroy(nfsd_serv
); /* Release server */
139 nfsd_racache_shutdown();
140 nfs4_state_shutdown();
148 update_thread_usage(int busy_threads
)
150 unsigned long prev_call
;
154 spin_lock(&nfsd_call_lock
);
155 prev_call
= nfsd_last_call
;
156 nfsd_last_call
= jiffies
;
157 decile
= busy_threads
*10/nfsdstats
.th_cnt
;
158 if (decile
>0 && decile
<= 10) {
159 diff
= nfsd_last_call
- prev_call
;
160 if ( (nfsdstats
.th_usage
[decile
-1] += diff
) >= NFSD_USAGE_WRAP
)
161 nfsdstats
.th_usage
[decile
-1] -= NFSD_USAGE_WRAP
;
163 nfsdstats
.th_fullcnt
++;
165 spin_unlock(&nfsd_call_lock
);
169 * This is the NFS server kernel thread
172 nfsd(struct svc_rqst
*rqstp
)
174 struct svc_serv
*serv
= rqstp
->rq_server
;
175 struct fs_struct
*fsp
;
178 sigset_t shutdown_mask
, allowed_mask
;
180 /* Lock module and set up kernel thread */
183 current
->rlim
[RLIMIT_FSIZE
].rlim_cur
= RLIM_INFINITY
;
185 /* After daemonize() this kernel thread shares current->fs
186 * with the init process. We need to create files with a
187 * umask of 0 instead of init's umask. */
188 fsp
= copy_fs_struct(current
->fs
);
190 printk("Unable to start nfsd thread: out of memory\n");
195 current
->fs
->umask
= 0;
197 siginitsetinv(&shutdown_mask
, SHUTDOWN_SIGS
);
198 siginitsetinv(&allowed_mask
, ALLOWED_SIGS
);
202 lockd_up(); /* start lockd */
205 list_add(&me
.list
, &nfsd_list
);
210 * We want less throttling in balance_dirty_pages() so that nfs to
211 * localhost doesn't cause nfsd to lock up due to all the client's
214 current
->flags
|= PF_LESS_THROTTLE
;
217 * The main request loop
220 /* Block all but the shutdown signals */
221 sigprocmask(SIG_SETMASK
, &shutdown_mask
, NULL
);
224 * Find a socket with data available and call its
227 while ((err
= svc_recv(serv
, rqstp
,
228 60*60*HZ
)) == -EAGAIN
)
232 update_thread_usage(atomic_read(&nfsd_busy
));
233 atomic_inc(&nfsd_busy
);
235 /* Lock the export hash tables for reading. */
238 /* Process request with signals blocked. */
239 sigprocmask(SIG_SETMASK
, &allowed_mask
, NULL
);
241 svc_process(serv
, rqstp
);
243 /* Unlock export hash tables */
245 update_thread_usage(atomic_read(&nfsd_busy
));
246 atomic_dec(&nfsd_busy
);
250 printk(KERN_WARNING
"nfsd: terminating on error %d\n", -err
);
254 for (signo
= 1; signo
<= _NSIG
; signo
++)
255 if (sigismember(¤t
->pending
.signal
, signo
) &&
256 !sigismember(¤t
->blocked
, signo
))
266 /* Check if this is last thread */
267 if (serv
->sv_nrthreads
==1) {
269 printk(KERN_WARNING
"nfsd: last server has exited\n");
270 if (err
!= SIG_NOCLEAN
) {
271 printk(KERN_WARNING
"nfsd: unexporting all filesystems\n");
275 nfsd_racache_shutdown(); /* release read-ahead cache */
276 nfs4_state_shutdown();
282 /* Release the thread */
283 svc_exit_thread(rqstp
);
286 module_put_and_exit(0);
290 nfsd_dispatch(struct svc_rqst
*rqstp
, u32
*statp
)
292 struct svc_procedure
*proc
;
297 dprintk("nfsd_dispatch: vers %d proc %d\n",
298 rqstp
->rq_vers
, rqstp
->rq_proc
);
299 proc
= rqstp
->rq_procinfo
;
301 /* Check whether we have this call in the cache. */
302 switch (nfsd_cache_lookup(rqstp
, proc
->pc_cachetype
)) {
312 /* Decode arguments */
313 xdr
= proc
->pc_decode
;
314 if (xdr
&& !xdr(rqstp
, (u32
*)rqstp
->rq_arg
.head
[0].iov_base
,
316 dprintk("nfsd: failed to decode arguments!\n");
317 nfsd_cache_update(rqstp
, RC_NOCACHE
, NULL
);
318 *statp
= rpc_garbage_args
;
322 /* need to grab the location to store the status, as
323 * nfsv4 does some encoding while processing
325 nfserrp
= rqstp
->rq_res
.head
[0].iov_base
326 + rqstp
->rq_res
.head
[0].iov_len
;
327 rqstp
->rq_res
.head
[0].iov_len
+= sizeof(u32
);
329 /* Now call the procedure handler, and encode NFS status. */
330 nfserr
= proc
->pc_func(rqstp
, rqstp
->rq_argp
, rqstp
->rq_resp
);
331 if (nfserr
== nfserr_dropit
) {
332 dprintk("nfsd: Dropping request due to malloc failure!\n");
333 nfsd_cache_update(rqstp
, RC_NOCACHE
, NULL
);
337 if (rqstp
->rq_proc
!= 0)
341 * For NFSv2, additional info is never returned in case of an error.
343 if (!(nfserr
&& rqstp
->rq_vers
== 2)) {
344 xdr
= proc
->pc_encode
;
345 if (xdr
&& !xdr(rqstp
, nfserrp
,
347 /* Failed to encode result. Release cache entry */
348 dprintk("nfsd: failed to encode result!\n");
349 nfsd_cache_update(rqstp
, RC_NOCACHE
, NULL
);
350 *statp
= rpc_system_err
;
355 /* Store reply in cache. */
356 nfsd_cache_update(rqstp
, proc
->pc_cachetype
, statp
+ 1);
360 extern struct svc_version nfsd_version2
, nfsd_version3
, nfsd_version4
;
362 static struct svc_version
* nfsd_version
[] = {
363 [2] = &nfsd_version2
,
364 #if defined(CONFIG_NFSD_V3)
365 [3] = &nfsd_version3
,
367 #if defined(CONFIG_NFSD_V4)
368 [4] = &nfsd_version4
,
372 #define NFSD_NRVERS (sizeof(nfsd_version)/sizeof(nfsd_version[0]))
373 struct svc_program nfsd_program
= {
374 .pg_prog
= NFS_PROGRAM
, /* program number */
375 .pg_nvers
= NFSD_NRVERS
, /* nr of entries in nfsd_version */
376 .pg_vers
= nfsd_version
, /* version table */
377 .pg_name
= "nfsd", /* program name */
378 .pg_class
= "nfsd", /* authentication class */
379 .pg_stats
= &nfsd_svcstats
, /* version table */