2 * linux/fs/nfs/callback.c
4 * Copyright (C) 2004 Trond Myklebust
6 * NFSv4 callback handling
9 #include <linux/completion.h>
11 #include <linux/module.h>
12 #include <linux/sunrpc/svc.h>
13 #include <linux/sunrpc/svcsock.h>
14 #include <linux/nfs_fs.h>
15 #include <linux/mutex.h>
16 #include <linux/freezer.h>
17 #include <linux/kthread.h>
18 #include <linux/sunrpc/svcauth_gss.h>
19 #include <linux/sunrpc/bc_xprt.h>
21 #include <net/inet_sock.h>
28 #define NFSDBG_FACILITY NFSDBG_CALLBACK
30 struct nfs_callback_data
{
32 struct svc_serv
*serv
;
33 struct svc_rqst
*rqst
;
34 struct task_struct
*task
;
37 static struct nfs_callback_data nfs_callback_info
[NFS4_MAX_MINOR_VERSION
+ 1];
38 static DEFINE_MUTEX(nfs_callback_mutex
);
39 static struct svc_program nfs4_callback_program
;
41 unsigned short nfs_callback_tcpport6
;
43 static int nfs4_callback_up_net(struct svc_serv
*serv
, struct net
*net
)
46 struct nfs_net
*nn
= net_generic(net
, nfs_net_id
);
48 ret
= svc_create_xprt(serv
, "tcp", net
, PF_INET
,
49 nfs_callback_set_tcpport
, SVC_SOCK_ANONYMOUS
);
52 nn
->nfs_callback_tcpport
= ret
;
53 dprintk("NFS: Callback listener port = %u (af %u, net %p)\n",
54 nn
->nfs_callback_tcpport
, PF_INET
, net
);
56 ret
= svc_create_xprt(serv
, "tcp", net
, PF_INET6
,
57 nfs_callback_set_tcpport
, SVC_SOCK_ANONYMOUS
);
59 nfs_callback_tcpport6
= ret
;
60 dprintk("NFS: Callback listener port = %u (af %u, net %p)\n",
61 nfs_callback_tcpport6
, PF_INET6
, net
);
62 } else if (ret
!= -EAFNOSUPPORT
)
67 return (ret
) ? ret
: -ENOMEM
;
71 * This is the NFSv4 callback kernel thread.
74 nfs4_callback_svc(void *vrqstp
)
77 struct svc_rqst
*rqstp
= vrqstp
;
81 while (!kthread_should_stop()) {
83 * Listen for a request on the socket
85 err
= svc_recv(rqstp
, MAX_SCHEDULE_TIMEOUT
);
86 if (err
== -EAGAIN
|| err
== -EINTR
) {
92 printk(KERN_WARNING
"NFS: %s: unexpected error "
93 "from svc_recv (%d)\n", __func__
, err
);
96 schedule_timeout_uninterruptible(HZ
);
106 * Prepare to bring up the NFSv4 callback service
108 static struct svc_rqst
*
109 nfs4_callback_up(struct svc_serv
*serv
)
111 return svc_prepare_thread(serv
, &serv
->sv_pools
[0], NUMA_NO_NODE
);
114 #if defined(CONFIG_NFS_V4_1)
115 static int nfs41_callback_up_net(struct svc_serv
*serv
, struct net
*net
)
118 * Create an svc_sock for the back channel service that shares the
119 * fore channel connection.
120 * Returns the input port (0) and sets the svc_serv bc_xprt on success
122 return svc_create_xprt(serv
, "tcp-bc", net
, PF_INET
, 0,
127 * The callback service for NFSv4.1 callbacks
130 nfs41_callback_svc(void *vrqstp
)
132 struct svc_rqst
*rqstp
= vrqstp
;
133 struct svc_serv
*serv
= rqstp
->rq_server
;
134 struct rpc_rqst
*req
;
140 while (!kthread_should_stop()) {
141 prepare_to_wait(&serv
->sv_cb_waitq
, &wq
, TASK_INTERRUPTIBLE
);
142 spin_lock_bh(&serv
->sv_cb_lock
);
143 if (!list_empty(&serv
->sv_cb_list
)) {
144 req
= list_first_entry(&serv
->sv_cb_list
,
145 struct rpc_rqst
, rq_bc_list
);
146 list_del(&req
->rq_bc_list
);
147 spin_unlock_bh(&serv
->sv_cb_lock
);
148 dprintk("Invoking bc_svc_process()\n");
149 error
= bc_svc_process(serv
, req
, rqstp
);
150 dprintk("bc_svc_process() returned w/ error code= %d\n",
153 spin_unlock_bh(&serv
->sv_cb_lock
);
156 finish_wait(&serv
->sv_cb_waitq
, &wq
);
162 * Bring up the NFSv4.1 callback service
164 static struct svc_rqst
*
165 nfs41_callback_up(struct svc_serv
*serv
)
167 struct svc_rqst
*rqstp
;
169 INIT_LIST_HEAD(&serv
->sv_cb_list
);
170 spin_lock_init(&serv
->sv_cb_lock
);
171 init_waitqueue_head(&serv
->sv_cb_waitq
);
172 rqstp
= svc_prepare_thread(serv
, &serv
->sv_pools
[0], NUMA_NO_NODE
);
174 svc_xprt_put(serv
->sv_bc_xprt
);
175 serv
->sv_bc_xprt
= NULL
;
177 dprintk("--> %s return %ld\n", __func__
,
178 IS_ERR(rqstp
) ? PTR_ERR(rqstp
) : 0);
182 static inline int nfs_minorversion_callback_svc_setup(u32 minorversion
,
183 struct svc_serv
*serv
,
184 struct svc_rqst
**rqstpp
, int (**callback_svc
)(void *vrqstp
))
187 *rqstpp
= nfs41_callback_up(serv
);
188 *callback_svc
= nfs41_callback_svc
;
193 static inline void nfs_callback_bc_serv(u32 minorversion
, struct rpc_xprt
*xprt
,
194 struct svc_serv
*serv
)
198 * Save the svc_serv in the transport so that it can
199 * be referenced when the session backchannel is initialized
201 xprt
->bc_serv
= serv
;
204 static int nfs41_callback_up_net(struct svc_serv
*serv
, struct net
*net
)
209 static inline int nfs_minorversion_callback_svc_setup(u32 minorversion
,
210 struct svc_serv
*serv
,
211 struct svc_rqst
**rqstpp
, int (**callback_svc
)(void *vrqstp
))
216 static inline void nfs_callback_bc_serv(u32 minorversion
, struct rpc_xprt
*xprt
,
217 struct svc_serv
*serv
)
220 #endif /* CONFIG_NFS_V4_1 */
222 static int nfs_callback_start_svc(int minorversion
, struct rpc_xprt
*xprt
,
223 struct svc_serv
*serv
)
225 struct svc_rqst
*rqstp
;
226 int (*callback_svc
)(void *vrqstp
);
227 struct nfs_callback_data
*cb_info
= &nfs_callback_info
[minorversion
];
230 int minorversion_setup
;
232 nfs_callback_bc_serv(minorversion
, xprt
, serv
);
237 minorversion_setup
= nfs_minorversion_callback_svc_setup(minorversion
,
238 serv
, &rqstp
, &callback_svc
);
239 if (!minorversion_setup
) {
240 /* v4.0 callback setup */
241 rqstp
= nfs4_callback_up(serv
);
242 callback_svc
= nfs4_callback_svc
;
246 return PTR_ERR(rqstp
);
248 svc_sock_update_bufs(serv
);
250 sprintf(svc_name
, "nfsv4.%u-svc", minorversion
);
251 cb_info
->serv
= serv
;
252 cb_info
->rqst
= rqstp
;
253 cb_info
->task
= kthread_run(callback_svc
, cb_info
->rqst
, svc_name
);
254 if (IS_ERR(cb_info
->task
)) {
255 ret
= PTR_ERR(cb_info
->task
);
256 svc_exit_thread(cb_info
->rqst
);
257 cb_info
->rqst
= NULL
;
258 cb_info
->task
= NULL
;
259 return PTR_ERR(cb_info
->task
);
261 dprintk("nfs_callback_up: service started\n");
265 static int nfs_callback_up_net(int minorversion
, struct svc_serv
*serv
, struct net
*net
)
269 dprintk("NFS: create per-net callback data; net=%p\n", net
);
271 ret
= svc_bind(serv
, net
);
273 printk(KERN_WARNING
"NFS: bind callback service failed\n");
277 switch (minorversion
) {
279 ret
= nfs4_callback_up_net(serv
, net
);
282 ret
= nfs41_callback_up_net(serv
, net
);
285 printk(KERN_ERR
"NFS: unknown callback version: %d\n",
292 printk(KERN_ERR
"NFS: callback service start failed\n");
298 svc_rpcb_cleanup(serv
, net
);
300 dprintk("NFS: Couldn't create callback socket: err = %d; "
301 "net = %p\n", ret
, net
);
305 static struct svc_serv
*nfs_callback_create_svc(int minorversion
)
307 struct nfs_callback_data
*cb_info
= &nfs_callback_info
[minorversion
];
308 struct svc_serv
*serv
;
311 * Check whether we're already up and running.
315 * Note: increase service usage, because later in case of error
316 * svc_destroy() will be called.
318 svc_get(cb_info
->serv
);
319 return cb_info
->serv
;
323 * Sanity check: if there's no task,
324 * we should be the first user ...
327 printk(KERN_WARNING
"nfs_callback_create_svc: no kthread, %d users??\n",
330 serv
= svc_create(&nfs4_callback_program
, NFS4_CALLBACK_BUFSIZE
, NULL
);
332 printk(KERN_ERR
"nfs_callback_create_svc: create service failed\n");
333 return ERR_PTR(-ENOMEM
);
335 /* As there is only one thread we need to over-ride the
336 * default maximum of 80 connections
338 serv
->sv_maxconn
= 1024;
339 dprintk("nfs_callback_create_svc: service created\n");
344 * Bring up the callback thread if it is not already up.
346 int nfs_callback_up(u32 minorversion
, struct rpc_xprt
*xprt
)
348 struct svc_serv
*serv
;
349 struct nfs_callback_data
*cb_info
= &nfs_callback_info
[minorversion
];
351 struct net
*net
= xprt
->xprt_net
;
353 mutex_lock(&nfs_callback_mutex
);
355 serv
= nfs_callback_create_svc(minorversion
);
361 ret
= nfs_callback_up_net(minorversion
, serv
, net
);
365 ret
= nfs_callback_start_svc(minorversion
, xprt
, serv
);
371 * svc_create creates the svc_serv with sv_nrthreads == 1, and then
372 * svc_prepare_thread increments that. So we need to call svc_destroy
373 * on both success and failure so that the refcount is 1 when the
379 mutex_unlock(&nfs_callback_mutex
);
383 svc_shutdown_net(serv
, net
);
384 dprintk("NFS: Couldn't create server thread; err = %d\n", ret
);
389 * Kill the callback thread if it's no longer being used.
391 void nfs_callback_down(int minorversion
, struct net
*net
)
393 struct nfs_callback_data
*cb_info
= &nfs_callback_info
[minorversion
];
395 mutex_lock(&nfs_callback_mutex
);
397 if (cb_info
->users
== 0 && cb_info
->task
!= NULL
) {
398 kthread_stop(cb_info
->task
);
399 svc_shutdown_net(cb_info
->serv
, net
);
400 svc_exit_thread(cb_info
->rqst
);
401 cb_info
->serv
= NULL
;
402 cb_info
->rqst
= NULL
;
403 cb_info
->task
= NULL
;
405 mutex_unlock(&nfs_callback_mutex
);
408 /* Boolean check of RPC_AUTH_GSS principal */
410 check_gss_callback_principal(struct nfs_client
*clp
, struct svc_rqst
*rqstp
)
412 char *p
= rqstp
->rq_cred
.cr_principal
;
414 if (rqstp
->rq_authop
->flavour
!= RPC_AUTH_GSS
)
417 /* No RPC_AUTH_GSS on NFSv4.1 back channel yet */
418 if (clp
->cl_minorversion
!= 0)
421 * It might just be a normal user principal, in which case
422 * userspace won't bother to tell us the name at all.
427 /* Expect a GSS_C_NT_HOSTBASED_NAME like "nfs@serverhostname" */
429 if (memcmp(p
, "nfs@", 4) != 0)
432 if (strcmp(p
, clp
->cl_hostname
) != 0)
438 * pg_authenticate method for nfsv4 callback threads.
440 * The authflavor has been negotiated, so an incorrect flavor is a server
441 * bug. Drop packets with incorrect authflavor.
443 * All other checking done after NFS decoding where the nfs_client can be
444 * found in nfs4_callback_compound
446 static int nfs_callback_authenticate(struct svc_rqst
*rqstp
)
448 switch (rqstp
->rq_authop
->flavour
) {
450 if (rqstp
->rq_proc
!= CB_NULL
)
454 /* No RPC_AUTH_GSS support yet in NFSv4.1 */
455 if (svc_is_backchannel(rqstp
))
462 * Define NFS4 callback program
464 static struct svc_version
*nfs4_callback_version
[] = {
465 [1] = &nfs4_callback_version1
,
466 [4] = &nfs4_callback_version4
,
469 static struct svc_stat nfs4_callback_stats
;
471 static struct svc_program nfs4_callback_program
= {
472 .pg_prog
= NFS4_CALLBACK
, /* RPC service number */
473 .pg_nvers
= ARRAY_SIZE(nfs4_callback_version
), /* Number of entries */
474 .pg_vers
= nfs4_callback_version
, /* version table */
475 .pg_name
= "NFSv4 callback", /* service name */
476 .pg_class
= "nfs", /* authentication class */
477 .pg_stats
= &nfs4_callback_stats
,
478 .pg_authenticate
= nfs_callback_authenticate
,