Root/fs/lockd/svc4proc.c

1/*
2 * linux/fs/lockd/svc4proc.c
3 *
4 * Lockd server procedures. We don't implement the NLM_*_RES
5 * procedures because we don't use the async procedures.
6 *
7 * Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
8 */
9
10#include <linux/types.h>
11#include <linux/time.h>
12#include <linux/lockd/lockd.h>
13#include <linux/lockd/share.h>
14
15#define NLMDBG_FACILITY NLMDBG_CLIENT
16
17/*
18 * Obtain client and file from arguments
19 */
20static __be32
21nlm4svc_retrieve_args(struct svc_rqst *rqstp, struct nlm_args *argp,
22            struct nlm_host **hostp, struct nlm_file **filp)
23{
24    struct nlm_host *host = NULL;
25    struct nlm_file *file = NULL;
26    struct nlm_lock *lock = &argp->lock;
27    __be32 error = 0;
28
29    /* nfsd callbacks must have been installed for this procedure */
30    if (!nlmsvc_ops)
31        return nlm_lck_denied_nolocks;
32
33    /* Obtain host handle */
34    if (!(host = nlmsvc_lookup_host(rqstp, lock->caller, lock->len))
35     || (argp->monitor && nsm_monitor(host) < 0))
36        goto no_locks;
37    *hostp = host;
38
39    /* Obtain file pointer. Not used by FREE_ALL call. */
40    if (filp != NULL) {
41        if ((error = nlm_lookup_file(rqstp, &file, &lock->fh)) != 0)
42            goto no_locks;
43        *filp = file;
44
45        /* Set up the missing parts of the file_lock structure */
46        lock->fl.fl_file = file->f_file;
47        lock->fl.fl_owner = (fl_owner_t) host;
48        lock->fl.fl_lmops = &nlmsvc_lock_operations;
49    }
50
51    return 0;
52
53no_locks:
54    nlmsvc_release_host(host);
55     if (error)
56        return error;
57    return nlm_lck_denied_nolocks;
58}
59
60/*
61 * NULL: Test for presence of service
62 */
63static __be32
64nlm4svc_proc_null(struct svc_rqst *rqstp, void *argp, void *resp)
65{
66    dprintk("lockd: NULL called\n");
67    return rpc_success;
68}
69
70/*
71 * TEST: Check for conflicting lock
72 */
73static __be32
74nlm4svc_proc_test(struct svc_rqst *rqstp, struct nlm_args *argp,
75                         struct nlm_res *resp)
76{
77    struct nlm_host *host;
78    struct nlm_file *file;
79    __be32 rc = rpc_success;
80
81    dprintk("lockd: TEST4 called\n");
82    resp->cookie = argp->cookie;
83
84    /* Obtain client and file */
85    if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
86        return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
87
88    /* Now check for conflicting locks */
89    resp->status = nlmsvc_testlock(rqstp, file, host, &argp->lock, &resp->lock, &resp->cookie);
90    if (resp->status == nlm_drop_reply)
91        rc = rpc_drop_reply;
92    else
93        dprintk("lockd: TEST4 status %d\n", ntohl(resp->status));
94
95    nlmsvc_release_host(host);
96    nlm_release_file(file);
97    return rc;
98}
99
100static __be32
101nlm4svc_proc_lock(struct svc_rqst *rqstp, struct nlm_args *argp,
102                         struct nlm_res *resp)
103{
104    struct nlm_host *host;
105    struct nlm_file *file;
106    __be32 rc = rpc_success;
107
108    dprintk("lockd: LOCK called\n");
109
110    resp->cookie = argp->cookie;
111
112    /* Obtain client and file */
113    if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
114        return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
115
116#if 0
117    /* If supplied state doesn't match current state, we assume it's
118     * an old request that time-warped somehow. Any error return would
119     * do in this case because it's irrelevant anyway.
120     *
121     * NB: We don't retrieve the remote host's state yet.
122     */
123    if (host->h_nsmstate && host->h_nsmstate != argp->state) {
124        resp->status = nlm_lck_denied_nolocks;
125    } else
126#endif
127
128    /* Now try to lock the file */
129    resp->status = nlmsvc_lock(rqstp, file, host, &argp->lock,
130                    argp->block, &argp->cookie,
131                    argp->reclaim);
132    if (resp->status == nlm_drop_reply)
133        rc = rpc_drop_reply;
134    else
135        dprintk("lockd: LOCK status %d\n", ntohl(resp->status));
136
137    nlmsvc_release_host(host);
138    nlm_release_file(file);
139    return rc;
140}
141
142static __be32
143nlm4svc_proc_cancel(struct svc_rqst *rqstp, struct nlm_args *argp,
144                           struct nlm_res *resp)
145{
146    struct nlm_host *host;
147    struct nlm_file *file;
148
149    dprintk("lockd: CANCEL called\n");
150
151    resp->cookie = argp->cookie;
152
153    /* Don't accept requests during grace period */
154    if (locks_in_grace()) {
155        resp->status = nlm_lck_denied_grace_period;
156        return rpc_success;
157    }
158
159    /* Obtain client and file */
160    if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
161        return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
162
163    /* Try to cancel request. */
164    resp->status = nlmsvc_cancel_blocked(file, &argp->lock);
165
166    dprintk("lockd: CANCEL status %d\n", ntohl(resp->status));
167    nlmsvc_release_host(host);
168    nlm_release_file(file);
169    return rpc_success;
170}
171
172/*
173 * UNLOCK: release a lock
174 */
175static __be32
176nlm4svc_proc_unlock(struct svc_rqst *rqstp, struct nlm_args *argp,
177                           struct nlm_res *resp)
178{
179    struct nlm_host *host;
180    struct nlm_file *file;
181
182    dprintk("lockd: UNLOCK called\n");
183
184    resp->cookie = argp->cookie;
185
186    /* Don't accept new lock requests during grace period */
187    if (locks_in_grace()) {
188        resp->status = nlm_lck_denied_grace_period;
189        return rpc_success;
190    }
191
192    /* Obtain client and file */
193    if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
194        return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
195
196    /* Now try to remove the lock */
197    resp->status = nlmsvc_unlock(file, &argp->lock);
198
199    dprintk("lockd: UNLOCK status %d\n", ntohl(resp->status));
200    nlmsvc_release_host(host);
201    nlm_release_file(file);
202    return rpc_success;
203}
204
205/*
206 * GRANTED: A server calls us to tell that a process' lock request
207 * was granted
208 */
209static __be32
210nlm4svc_proc_granted(struct svc_rqst *rqstp, struct nlm_args *argp,
211                            struct nlm_res *resp)
212{
213    resp->cookie = argp->cookie;
214
215    dprintk("lockd: GRANTED called\n");
216    resp->status = nlmclnt_grant(svc_addr(rqstp), &argp->lock);
217    dprintk("lockd: GRANTED status %d\n", ntohl(resp->status));
218    return rpc_success;
219}
220
221/*
222 * This is the generic lockd callback for async RPC calls
223 */
224static void nlm4svc_callback_exit(struct rpc_task *task, void *data)
225{
226    dprintk("lockd: %5u callback returned %d\n", task->tk_pid,
227            -task->tk_status);
228}
229
230static void nlm4svc_callback_release(void *data)
231{
232    nlmsvc_release_call(data);
233}
234
235static const struct rpc_call_ops nlm4svc_callback_ops = {
236    .rpc_call_done = nlm4svc_callback_exit,
237    .rpc_release = nlm4svc_callback_release,
238};
239
240/*
241 * `Async' versions of the above service routines. They aren't really,
242 * because we send the callback before the reply proper. I hope this
243 * doesn't break any clients.
244 */
245static __be32 nlm4svc_callback(struct svc_rqst *rqstp, u32 proc, struct nlm_args *argp,
246        __be32 (*func)(struct svc_rqst *, struct nlm_args *, struct nlm_res *))
247{
248    struct nlm_host *host;
249    struct nlm_rqst *call;
250    __be32 stat;
251
252    host = nlmsvc_lookup_host(rqstp,
253                  argp->lock.caller,
254                  argp->lock.len);
255    if (host == NULL)
256        return rpc_system_err;
257
258    call = nlm_alloc_call(host);
259    if (call == NULL)
260        return rpc_system_err;
261
262    stat = func(rqstp, argp, &call->a_res);
263    if (stat != 0) {
264        nlmsvc_release_call(call);
265        return stat;
266    }
267
268    call->a_flags = RPC_TASK_ASYNC;
269    if (nlm_async_reply(call, proc, &nlm4svc_callback_ops) < 0)
270        return rpc_system_err;
271    return rpc_success;
272}
273
274static __be32 nlm4svc_proc_test_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
275                         void *resp)
276{
277    dprintk("lockd: TEST_MSG called\n");
278    return nlm4svc_callback(rqstp, NLMPROC_TEST_RES, argp, nlm4svc_proc_test);
279}
280
281static __be32 nlm4svc_proc_lock_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
282                         void *resp)
283{
284    dprintk("lockd: LOCK_MSG called\n");
285    return nlm4svc_callback(rqstp, NLMPROC_LOCK_RES, argp, nlm4svc_proc_lock);
286}
287
288static __be32 nlm4svc_proc_cancel_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
289                           void *resp)
290{
291    dprintk("lockd: CANCEL_MSG called\n");
292    return nlm4svc_callback(rqstp, NLMPROC_CANCEL_RES, argp, nlm4svc_proc_cancel);
293}
294
295static __be32 nlm4svc_proc_unlock_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
296                                               void *resp)
297{
298    dprintk("lockd: UNLOCK_MSG called\n");
299    return nlm4svc_callback(rqstp, NLMPROC_UNLOCK_RES, argp, nlm4svc_proc_unlock);
300}
301
302static __be32 nlm4svc_proc_granted_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
303                                                void *resp)
304{
305    dprintk("lockd: GRANTED_MSG called\n");
306    return nlm4svc_callback(rqstp, NLMPROC_GRANTED_RES, argp, nlm4svc_proc_granted);
307}
308
309/*
310 * SHARE: create a DOS share or alter existing share.
311 */
312static __be32
313nlm4svc_proc_share(struct svc_rqst *rqstp, struct nlm_args *argp,
314                          struct nlm_res *resp)
315{
316    struct nlm_host *host;
317    struct nlm_file *file;
318
319    dprintk("lockd: SHARE called\n");
320
321    resp->cookie = argp->cookie;
322
323    /* Don't accept new lock requests during grace period */
324    if (locks_in_grace() && !argp->reclaim) {
325        resp->status = nlm_lck_denied_grace_period;
326        return rpc_success;
327    }
328
329    /* Obtain client and file */
330    if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
331        return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
332
333    /* Now try to create the share */
334    resp->status = nlmsvc_share_file(host, file, argp);
335
336    dprintk("lockd: SHARE status %d\n", ntohl(resp->status));
337    nlmsvc_release_host(host);
338    nlm_release_file(file);
339    return rpc_success;
340}
341
342/*
343 * UNSHARE: Release a DOS share.
344 */
345static __be32
346nlm4svc_proc_unshare(struct svc_rqst *rqstp, struct nlm_args *argp,
347                            struct nlm_res *resp)
348{
349    struct nlm_host *host;
350    struct nlm_file *file;
351
352    dprintk("lockd: UNSHARE called\n");
353
354    resp->cookie = argp->cookie;
355
356    /* Don't accept requests during grace period */
357    if (locks_in_grace()) {
358        resp->status = nlm_lck_denied_grace_period;
359        return rpc_success;
360    }
361
362    /* Obtain client and file */
363    if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
364        return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
365
366    /* Now try to lock the file */
367    resp->status = nlmsvc_unshare_file(host, file, argp);
368
369    dprintk("lockd: UNSHARE status %d\n", ntohl(resp->status));
370    nlmsvc_release_host(host);
371    nlm_release_file(file);
372    return rpc_success;
373}
374
375/*
376 * NM_LOCK: Create an unmonitored lock
377 */
378static __be32
379nlm4svc_proc_nm_lock(struct svc_rqst *rqstp, struct nlm_args *argp,
380                            struct nlm_res *resp)
381{
382    dprintk("lockd: NM_LOCK called\n");
383
384    argp->monitor = 0; /* just clean the monitor flag */
385    return nlm4svc_proc_lock(rqstp, argp, resp);
386}
387
388/*
389 * FREE_ALL: Release all locks and shares held by client
390 */
391static __be32
392nlm4svc_proc_free_all(struct svc_rqst *rqstp, struct nlm_args *argp,
393                         void *resp)
394{
395    struct nlm_host *host;
396
397    /* Obtain client */
398    if (nlm4svc_retrieve_args(rqstp, argp, &host, NULL))
399        return rpc_success;
400
401    nlmsvc_free_host_resources(host);
402    nlmsvc_release_host(host);
403    return rpc_success;
404}
405
406/*
407 * SM_NOTIFY: private callback from statd (not part of official NLM proto)
408 */
409static __be32
410nlm4svc_proc_sm_notify(struct svc_rqst *rqstp, struct nlm_reboot *argp,
411                          void *resp)
412{
413    dprintk("lockd: SM_NOTIFY called\n");
414
415    if (!nlm_privileged_requester(rqstp)) {
416        char buf[RPC_MAX_ADDRBUFLEN];
417        printk(KERN_WARNING "lockd: rejected NSM callback from %s\n",
418                svc_print_addr(rqstp, buf, sizeof(buf)));
419        return rpc_system_err;
420    }
421
422    nlm_host_rebooted(argp);
423    return rpc_success;
424}
425
426/*
427 * client sent a GRANTED_RES, let's remove the associated block
428 */
429static __be32
430nlm4svc_proc_granted_res(struct svc_rqst *rqstp, struct nlm_res *argp,
431                                                void *resp)
432{
433        if (!nlmsvc_ops)
434                return rpc_success;
435
436        dprintk("lockd: GRANTED_RES called\n");
437
438        nlmsvc_grant_reply(&argp->cookie, argp->status);
439        return rpc_success;
440}
441
442
443/*
444 * NLM Server procedures.
445 */
446
447#define nlm4svc_encode_norep nlm4svc_encode_void
448#define nlm4svc_decode_norep nlm4svc_decode_void
449#define nlm4svc_decode_testres nlm4svc_decode_void
450#define nlm4svc_decode_lockres nlm4svc_decode_void
451#define nlm4svc_decode_unlockres nlm4svc_decode_void
452#define nlm4svc_decode_cancelres nlm4svc_decode_void
453#define nlm4svc_decode_grantedres nlm4svc_decode_void
454
455#define nlm4svc_proc_none nlm4svc_proc_null
456#define nlm4svc_proc_test_res nlm4svc_proc_null
457#define nlm4svc_proc_lock_res nlm4svc_proc_null
458#define nlm4svc_proc_cancel_res nlm4svc_proc_null
459#define nlm4svc_proc_unlock_res nlm4svc_proc_null
460
461struct nlm_void { int dummy; };
462
463#define PROC(name, xargt, xrest, argt, rest, respsize) \
464 { .pc_func = (svc_procfunc) nlm4svc_proc_##name, \
465   .pc_decode = (kxdrproc_t) nlm4svc_decode_##xargt, \
466   .pc_encode = (kxdrproc_t) nlm4svc_encode_##xrest, \
467   .pc_release = NULL, \
468   .pc_argsize = sizeof(struct nlm_##argt), \
469   .pc_ressize = sizeof(struct nlm_##rest), \
470   .pc_xdrressize = respsize, \
471 }
472#define Ck (1+XDR_QUADLEN(NLM_MAXCOOKIELEN)) /* cookie */
473#define No (1+1024/4) /* netobj */
474#define St 1 /* status */
475#define Rg 4 /* range (offset + length) */
476struct svc_procedure nlmsvc_procedures4[] = {
477  PROC(null, void, void, void, void, 1),
478  PROC(test, testargs, testres, args, res, Ck+St+2+No+Rg),
479  PROC(lock, lockargs, res, args, res, Ck+St),
480  PROC(cancel, cancargs, res, args, res, Ck+St),
481  PROC(unlock, unlockargs, res, args, res, Ck+St),
482  PROC(granted, testargs, res, args, res, Ck+St),
483  PROC(test_msg, testargs, norep, args, void, 1),
484  PROC(lock_msg, lockargs, norep, args, void, 1),
485  PROC(cancel_msg, cancargs, norep, args, void, 1),
486  PROC(unlock_msg, unlockargs, norep, args, void, 1),
487  PROC(granted_msg, testargs, norep, args, void, 1),
488  PROC(test_res, testres, norep, res, void, 1),
489  PROC(lock_res, lockres, norep, res, void, 1),
490  PROC(cancel_res, cancelres, norep, res, void, 1),
491  PROC(unlock_res, unlockres, norep, res, void, 1),
492  PROC(granted_res, res, norep, res, void, 1),
493  /* statd callback */
494  PROC(sm_notify, reboot, void, reboot, void, 1),
495  PROC(none, void, void, void, void, 0),
496  PROC(none, void, void, void, void, 0),
497  PROC(none, void, void, void, void, 0),
498  PROC(share, shareargs, shareres, args, res, Ck+St+1),
499  PROC(unshare, shareargs, shareres, args, res, Ck+St+1),
500  PROC(nm_lock, lockargs, res, args, res, Ck+St),
501  PROC(free_all, notify, void, args, void, 1),
502
503};
504

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