1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * linux/fs/nfs/delegation.c |
4 | * |
5 | * Copyright (C) 2004 Trond Myklebust |
6 | * |
7 | * NFS file delegation management |
8 | * |
9 | */ |
10 | #include <linux/completion.h> |
11 | #include <linux/kthread.h> |
12 | #include <linux/module.h> |
13 | #include <linux/sched.h> |
14 | #include <linux/slab.h> |
15 | #include <linux/spinlock.h> |
16 | #include <linux/iversion.h> |
17 | |
18 | #include <linux/nfs4.h> |
19 | #include <linux/nfs_fs.h> |
20 | #include <linux/nfs_xdr.h> |
21 | |
22 | #include "nfs4_fs.h" |
23 | #include "nfs4session.h" |
24 | #include "delegation.h" |
25 | #include "internal.h" |
26 | #include "nfs4trace.h" |
27 | |
28 | #define NFS_DEFAULT_DELEGATION_WATERMARK (5000U) |
29 | |
30 | static atomic_long_t nfs_active_delegations; |
31 | static unsigned nfs_delegation_watermark = NFS_DEFAULT_DELEGATION_WATERMARK; |
32 | |
33 | static void __nfs_free_delegation(struct nfs_delegation *delegation) |
34 | { |
35 | put_cred(cred: delegation->cred); |
36 | delegation->cred = NULL; |
37 | kfree_rcu(delegation, rcu); |
38 | } |
39 | |
40 | static void nfs_mark_delegation_revoked(struct nfs_delegation *delegation) |
41 | { |
42 | if (!test_and_set_bit(nr: NFS_DELEGATION_REVOKED, addr: &delegation->flags)) { |
43 | delegation->stateid.type = NFS4_INVALID_STATEID_TYPE; |
44 | atomic_long_dec(v: &nfs_active_delegations); |
45 | if (!test_bit(NFS_DELEGATION_RETURNING, &delegation->flags)) |
46 | nfs_clear_verifier_delegated(inode: delegation->inode); |
47 | } |
48 | } |
49 | |
50 | static struct nfs_delegation *nfs_get_delegation(struct nfs_delegation *delegation) |
51 | { |
52 | refcount_inc(r: &delegation->refcount); |
53 | return delegation; |
54 | } |
55 | |
56 | static void nfs_put_delegation(struct nfs_delegation *delegation) |
57 | { |
58 | if (refcount_dec_and_test(r: &delegation->refcount)) |
59 | __nfs_free_delegation(delegation); |
60 | } |
61 | |
62 | static void nfs_free_delegation(struct nfs_delegation *delegation) |
63 | { |
64 | nfs_mark_delegation_revoked(delegation); |
65 | nfs_put_delegation(delegation); |
66 | } |
67 | |
68 | /** |
69 | * nfs_mark_delegation_referenced - set delegation's REFERENCED flag |
70 | * @delegation: delegation to process |
71 | * |
72 | */ |
73 | void nfs_mark_delegation_referenced(struct nfs_delegation *delegation) |
74 | { |
75 | set_bit(nr: NFS_DELEGATION_REFERENCED, addr: &delegation->flags); |
76 | } |
77 | |
78 | static void nfs_mark_return_delegation(struct nfs_server *server, |
79 | struct nfs_delegation *delegation) |
80 | { |
81 | set_bit(nr: NFS_DELEGATION_RETURN, addr: &delegation->flags); |
82 | set_bit(nr: NFS4CLNT_DELEGRETURN, addr: &server->nfs_client->cl_state); |
83 | } |
84 | |
85 | static bool |
86 | nfs4_is_valid_delegation(const struct nfs_delegation *delegation, |
87 | fmode_t flags) |
88 | { |
89 | if (delegation != NULL && (delegation->type & flags) == flags && |
90 | !test_bit(NFS_DELEGATION_REVOKED, &delegation->flags) && |
91 | !test_bit(NFS_DELEGATION_RETURNING, &delegation->flags)) |
92 | return true; |
93 | return false; |
94 | } |
95 | |
96 | struct nfs_delegation *nfs4_get_valid_delegation(const struct inode *inode) |
97 | { |
98 | struct nfs_delegation *delegation; |
99 | |
100 | delegation = rcu_dereference(NFS_I(inode)->delegation); |
101 | if (nfs4_is_valid_delegation(delegation, flags: 0)) |
102 | return delegation; |
103 | return NULL; |
104 | } |
105 | |
106 | static int |
107 | nfs4_do_check_delegation(struct inode *inode, fmode_t flags, bool mark) |
108 | { |
109 | struct nfs_delegation *delegation; |
110 | int ret = 0; |
111 | |
112 | flags &= FMODE_READ|FMODE_WRITE; |
113 | rcu_read_lock(); |
114 | delegation = rcu_dereference(NFS_I(inode)->delegation); |
115 | if (nfs4_is_valid_delegation(delegation, flags)) { |
116 | if (mark) |
117 | nfs_mark_delegation_referenced(delegation); |
118 | ret = 1; |
119 | } |
120 | rcu_read_unlock(); |
121 | return ret; |
122 | } |
123 | /** |
124 | * nfs4_have_delegation - check if inode has a delegation, mark it |
125 | * NFS_DELEGATION_REFERENCED if there is one. |
126 | * @inode: inode to check |
127 | * @flags: delegation types to check for |
128 | * |
129 | * Returns one if inode has the indicated delegation, otherwise zero. |
130 | */ |
131 | int nfs4_have_delegation(struct inode *inode, fmode_t flags) |
132 | { |
133 | return nfs4_do_check_delegation(inode, flags, mark: true); |
134 | } |
135 | |
136 | /* |
137 | * nfs4_check_delegation - check if inode has a delegation, do not mark |
138 | * NFS_DELEGATION_REFERENCED if it has one. |
139 | */ |
140 | int nfs4_check_delegation(struct inode *inode, fmode_t flags) |
141 | { |
142 | return nfs4_do_check_delegation(inode, flags, mark: false); |
143 | } |
144 | |
145 | static int nfs_delegation_claim_locks(struct nfs4_state *state, const nfs4_stateid *stateid) |
146 | { |
147 | struct inode *inode = state->inode; |
148 | struct file_lock *fl; |
149 | struct file_lock_context *flctx = locks_inode_context(inode); |
150 | struct list_head *list; |
151 | int status = 0; |
152 | |
153 | if (flctx == NULL) |
154 | goto out; |
155 | |
156 | list = &flctx->flc_posix; |
157 | spin_lock(lock: &flctx->flc_lock); |
158 | restart: |
159 | list_for_each_entry(fl, list, fl_list) { |
160 | if (nfs_file_open_context(filp: fl->fl_file)->state != state) |
161 | continue; |
162 | spin_unlock(lock: &flctx->flc_lock); |
163 | status = nfs4_lock_delegation_recall(fl, state, stateid); |
164 | if (status < 0) |
165 | goto out; |
166 | spin_lock(lock: &flctx->flc_lock); |
167 | } |
168 | if (list == &flctx->flc_posix) { |
169 | list = &flctx->flc_flock; |
170 | goto restart; |
171 | } |
172 | spin_unlock(lock: &flctx->flc_lock); |
173 | out: |
174 | return status; |
175 | } |
176 | |
177 | static int nfs_delegation_claim_opens(struct inode *inode, |
178 | const nfs4_stateid *stateid, fmode_t type) |
179 | { |
180 | struct nfs_inode *nfsi = NFS_I(inode); |
181 | struct nfs_open_context *ctx; |
182 | struct nfs4_state_owner *sp; |
183 | struct nfs4_state *state; |
184 | unsigned int seq; |
185 | int err; |
186 | |
187 | again: |
188 | rcu_read_lock(); |
189 | list_for_each_entry_rcu(ctx, &nfsi->open_files, list) { |
190 | state = ctx->state; |
191 | if (state == NULL) |
192 | continue; |
193 | if (!test_bit(NFS_DELEGATED_STATE, &state->flags)) |
194 | continue; |
195 | if (!nfs4_valid_open_stateid(state)) |
196 | continue; |
197 | if (!nfs4_stateid_match(dst: &state->stateid, src: stateid)) |
198 | continue; |
199 | if (!get_nfs_open_context(ctx)) |
200 | continue; |
201 | rcu_read_unlock(); |
202 | sp = state->owner; |
203 | /* Block nfs4_proc_unlck */ |
204 | mutex_lock(&sp->so_delegreturn_mutex); |
205 | seq = raw_seqcount_begin(&sp->so_reclaim_seqcount); |
206 | err = nfs4_open_delegation_recall(ctx, state, stateid); |
207 | if (!err) |
208 | err = nfs_delegation_claim_locks(state, stateid); |
209 | if (!err && read_seqcount_retry(&sp->so_reclaim_seqcount, seq)) |
210 | err = -EAGAIN; |
211 | mutex_unlock(lock: &sp->so_delegreturn_mutex); |
212 | put_nfs_open_context(ctx); |
213 | if (err != 0) |
214 | return err; |
215 | goto again; |
216 | } |
217 | rcu_read_unlock(); |
218 | return 0; |
219 | } |
220 | |
221 | /** |
222 | * nfs_inode_reclaim_delegation - process a delegation reclaim request |
223 | * @inode: inode to process |
224 | * @cred: credential to use for request |
225 | * @type: delegation type |
226 | * @stateid: delegation stateid |
227 | * @pagemod_limit: write delegation "space_limit" |
228 | * |
229 | */ |
230 | void nfs_inode_reclaim_delegation(struct inode *inode, const struct cred *cred, |
231 | fmode_t type, const nfs4_stateid *stateid, |
232 | unsigned long pagemod_limit) |
233 | { |
234 | struct nfs_delegation *delegation; |
235 | const struct cred *oldcred = NULL; |
236 | |
237 | rcu_read_lock(); |
238 | delegation = rcu_dereference(NFS_I(inode)->delegation); |
239 | if (delegation != NULL) { |
240 | spin_lock(lock: &delegation->lock); |
241 | nfs4_stateid_copy(dst: &delegation->stateid, src: stateid); |
242 | delegation->type = type; |
243 | delegation->pagemod_limit = pagemod_limit; |
244 | oldcred = delegation->cred; |
245 | delegation->cred = get_cred(cred); |
246 | clear_bit(nr: NFS_DELEGATION_NEED_RECLAIM, addr: &delegation->flags); |
247 | if (test_and_clear_bit(nr: NFS_DELEGATION_REVOKED, |
248 | addr: &delegation->flags)) |
249 | atomic_long_inc(v: &nfs_active_delegations); |
250 | spin_unlock(lock: &delegation->lock); |
251 | rcu_read_unlock(); |
252 | put_cred(cred: oldcred); |
253 | trace_nfs4_reclaim_delegation(inode, fmode: type); |
254 | } else { |
255 | rcu_read_unlock(); |
256 | nfs_inode_set_delegation(inode, cred, type, stateid, |
257 | pagemod_limit); |
258 | } |
259 | } |
260 | |
261 | static int nfs_do_return_delegation(struct inode *inode, struct nfs_delegation *delegation, int issync) |
262 | { |
263 | const struct cred *cred; |
264 | int res = 0; |
265 | |
266 | if (!test_bit(NFS_DELEGATION_REVOKED, &delegation->flags)) { |
267 | spin_lock(lock: &delegation->lock); |
268 | cred = get_cred(cred: delegation->cred); |
269 | spin_unlock(lock: &delegation->lock); |
270 | res = nfs4_proc_delegreturn(inode, cred, |
271 | stateid: &delegation->stateid, |
272 | issync); |
273 | put_cred(cred); |
274 | } |
275 | return res; |
276 | } |
277 | |
278 | static struct inode *nfs_delegation_grab_inode(struct nfs_delegation *delegation) |
279 | { |
280 | struct inode *inode = NULL; |
281 | |
282 | spin_lock(lock: &delegation->lock); |
283 | if (delegation->inode != NULL) |
284 | inode = igrab(delegation->inode); |
285 | if (!inode) |
286 | set_bit(nr: NFS_DELEGATION_INODE_FREEING, addr: &delegation->flags); |
287 | spin_unlock(lock: &delegation->lock); |
288 | return inode; |
289 | } |
290 | |
291 | static struct nfs_delegation * |
292 | nfs_start_delegation_return_locked(struct nfs_inode *nfsi) |
293 | { |
294 | struct nfs_delegation *ret = NULL; |
295 | struct nfs_delegation *delegation = rcu_dereference(nfsi->delegation); |
296 | |
297 | if (delegation == NULL) |
298 | goto out; |
299 | spin_lock(lock: &delegation->lock); |
300 | if (!test_and_set_bit(nr: NFS_DELEGATION_RETURNING, addr: &delegation->flags)) { |
301 | clear_bit(nr: NFS_DELEGATION_RETURN_DELAYED, addr: &delegation->flags); |
302 | /* Refcount matched in nfs_end_delegation_return() */ |
303 | ret = nfs_get_delegation(delegation); |
304 | } |
305 | spin_unlock(lock: &delegation->lock); |
306 | if (ret) |
307 | nfs_clear_verifier_delegated(inode: &nfsi->vfs_inode); |
308 | out: |
309 | return ret; |
310 | } |
311 | |
312 | static struct nfs_delegation * |
313 | nfs_start_delegation_return(struct nfs_inode *nfsi) |
314 | { |
315 | struct nfs_delegation *delegation; |
316 | |
317 | rcu_read_lock(); |
318 | delegation = nfs_start_delegation_return_locked(nfsi); |
319 | rcu_read_unlock(); |
320 | return delegation; |
321 | } |
322 | |
323 | static void nfs_abort_delegation_return(struct nfs_delegation *delegation, |
324 | struct nfs_client *clp, int err) |
325 | { |
326 | |
327 | spin_lock(lock: &delegation->lock); |
328 | clear_bit(nr: NFS_DELEGATION_RETURNING, addr: &delegation->flags); |
329 | if (err == -EAGAIN) { |
330 | set_bit(nr: NFS_DELEGATION_RETURN_DELAYED, addr: &delegation->flags); |
331 | set_bit(nr: NFS4CLNT_DELEGRETURN_DELAYED, addr: &clp->cl_state); |
332 | } |
333 | spin_unlock(lock: &delegation->lock); |
334 | } |
335 | |
336 | static struct nfs_delegation * |
337 | nfs_detach_delegation_locked(struct nfs_inode *nfsi, |
338 | struct nfs_delegation *delegation, |
339 | struct nfs_client *clp) |
340 | { |
341 | struct nfs_delegation *deleg_cur = |
342 | rcu_dereference_protected(nfsi->delegation, |
343 | lockdep_is_held(&clp->cl_lock)); |
344 | |
345 | if (deleg_cur == NULL || delegation != deleg_cur) |
346 | return NULL; |
347 | |
348 | spin_lock(lock: &delegation->lock); |
349 | if (!delegation->inode) { |
350 | spin_unlock(lock: &delegation->lock); |
351 | return NULL; |
352 | } |
353 | list_del_rcu(entry: &delegation->super_list); |
354 | delegation->inode = NULL; |
355 | rcu_assign_pointer(nfsi->delegation, NULL); |
356 | spin_unlock(lock: &delegation->lock); |
357 | return delegation; |
358 | } |
359 | |
360 | static struct nfs_delegation *nfs_detach_delegation(struct nfs_inode *nfsi, |
361 | struct nfs_delegation *delegation, |
362 | struct nfs_server *server) |
363 | { |
364 | struct nfs_client *clp = server->nfs_client; |
365 | |
366 | spin_lock(lock: &clp->cl_lock); |
367 | delegation = nfs_detach_delegation_locked(nfsi, delegation, clp); |
368 | spin_unlock(lock: &clp->cl_lock); |
369 | return delegation; |
370 | } |
371 | |
372 | static struct nfs_delegation * |
373 | nfs_inode_detach_delegation(struct inode *inode) |
374 | { |
375 | struct nfs_inode *nfsi = NFS_I(inode); |
376 | struct nfs_server *server = NFS_SERVER(inode); |
377 | struct nfs_delegation *delegation; |
378 | |
379 | rcu_read_lock(); |
380 | delegation = rcu_dereference(nfsi->delegation); |
381 | if (delegation != NULL) |
382 | delegation = nfs_detach_delegation(nfsi, delegation, server); |
383 | rcu_read_unlock(); |
384 | return delegation; |
385 | } |
386 | |
387 | static void |
388 | nfs_update_delegation_cred(struct nfs_delegation *delegation, |
389 | const struct cred *cred) |
390 | { |
391 | const struct cred *old; |
392 | |
393 | if (cred_fscmp(delegation->cred, cred) != 0) { |
394 | old = xchg(&delegation->cred, get_cred(cred)); |
395 | put_cred(cred: old); |
396 | } |
397 | } |
398 | |
399 | static void |
400 | nfs_update_inplace_delegation(struct nfs_delegation *delegation, |
401 | const struct nfs_delegation *update) |
402 | { |
403 | if (nfs4_stateid_is_newer(s1: &update->stateid, s2: &delegation->stateid)) { |
404 | delegation->stateid.seqid = update->stateid.seqid; |
405 | smp_wmb(); |
406 | delegation->type = update->type; |
407 | delegation->pagemod_limit = update->pagemod_limit; |
408 | if (test_bit(NFS_DELEGATION_REVOKED, &delegation->flags)) { |
409 | delegation->change_attr = update->change_attr; |
410 | nfs_update_delegation_cred(delegation, cred: update->cred); |
411 | /* smp_mb__before_atomic() is implicit due to xchg() */ |
412 | clear_bit(nr: NFS_DELEGATION_REVOKED, addr: &delegation->flags); |
413 | atomic_long_inc(v: &nfs_active_delegations); |
414 | } |
415 | } |
416 | } |
417 | |
418 | /** |
419 | * nfs_inode_set_delegation - set up a delegation on an inode |
420 | * @inode: inode to which delegation applies |
421 | * @cred: cred to use for subsequent delegation processing |
422 | * @type: delegation type |
423 | * @stateid: delegation stateid |
424 | * @pagemod_limit: write delegation "space_limit" |
425 | * |
426 | * Returns zero on success, or a negative errno value. |
427 | */ |
428 | int nfs_inode_set_delegation(struct inode *inode, const struct cred *cred, |
429 | fmode_t type, |
430 | const nfs4_stateid *stateid, |
431 | unsigned long pagemod_limit) |
432 | { |
433 | struct nfs_server *server = NFS_SERVER(inode); |
434 | struct nfs_client *clp = server->nfs_client; |
435 | struct nfs_inode *nfsi = NFS_I(inode); |
436 | struct nfs_delegation *delegation, *old_delegation; |
437 | struct nfs_delegation *freeme = NULL; |
438 | int status = 0; |
439 | |
440 | delegation = kmalloc(size: sizeof(*delegation), GFP_KERNEL_ACCOUNT); |
441 | if (delegation == NULL) |
442 | return -ENOMEM; |
443 | nfs4_stateid_copy(dst: &delegation->stateid, src: stateid); |
444 | refcount_set(r: &delegation->refcount, n: 1); |
445 | delegation->type = type; |
446 | delegation->pagemod_limit = pagemod_limit; |
447 | delegation->change_attr = inode_peek_iversion_raw(inode); |
448 | delegation->cred = get_cred(cred); |
449 | delegation->inode = inode; |
450 | delegation->flags = 1<<NFS_DELEGATION_REFERENCED; |
451 | delegation->test_gen = 0; |
452 | spin_lock_init(&delegation->lock); |
453 | |
454 | spin_lock(lock: &clp->cl_lock); |
455 | old_delegation = rcu_dereference_protected(nfsi->delegation, |
456 | lockdep_is_held(&clp->cl_lock)); |
457 | if (old_delegation == NULL) |
458 | goto add_new; |
459 | /* Is this an update of the existing delegation? */ |
460 | if (nfs4_stateid_match_other(dst: &old_delegation->stateid, |
461 | src: &delegation->stateid)) { |
462 | spin_lock(lock: &old_delegation->lock); |
463 | nfs_update_inplace_delegation(delegation: old_delegation, |
464 | update: delegation); |
465 | spin_unlock(lock: &old_delegation->lock); |
466 | goto out; |
467 | } |
468 | if (!test_bit(NFS_DELEGATION_REVOKED, &old_delegation->flags)) { |
469 | /* |
470 | * Deal with broken servers that hand out two |
471 | * delegations for the same file. |
472 | * Allow for upgrades to a WRITE delegation, but |
473 | * nothing else. |
474 | */ |
475 | dfprintk(FILE, "%s: server %s handed out " |
476 | "a duplicate delegation!\n" , |
477 | __func__, clp->cl_hostname); |
478 | if (delegation->type == old_delegation->type || |
479 | !(delegation->type & FMODE_WRITE)) { |
480 | freeme = delegation; |
481 | delegation = NULL; |
482 | goto out; |
483 | } |
484 | if (test_and_set_bit(nr: NFS_DELEGATION_RETURNING, |
485 | addr: &old_delegation->flags)) |
486 | goto out; |
487 | } |
488 | freeme = nfs_detach_delegation_locked(nfsi, delegation: old_delegation, clp); |
489 | if (freeme == NULL) |
490 | goto out; |
491 | add_new: |
492 | /* |
493 | * If we didn't revalidate the change attribute before setting |
494 | * the delegation, then pre-emptively ask for a full attribute |
495 | * cache revalidation. |
496 | */ |
497 | spin_lock(lock: &inode->i_lock); |
498 | if (NFS_I(inode)->cache_validity & NFS_INO_INVALID_CHANGE) |
499 | nfs_set_cache_invalid(inode, |
500 | NFS_INO_INVALID_ATIME | NFS_INO_INVALID_CTIME | |
501 | NFS_INO_INVALID_MTIME | NFS_INO_INVALID_SIZE | |
502 | NFS_INO_INVALID_BLOCKS | NFS_INO_INVALID_NLINK | |
503 | NFS_INO_INVALID_OTHER | NFS_INO_INVALID_DATA | |
504 | NFS_INO_INVALID_ACCESS | NFS_INO_INVALID_ACL | |
505 | NFS_INO_INVALID_XATTR); |
506 | spin_unlock(lock: &inode->i_lock); |
507 | |
508 | list_add_tail_rcu(new: &delegation->super_list, head: &server->delegations); |
509 | rcu_assign_pointer(nfsi->delegation, delegation); |
510 | delegation = NULL; |
511 | |
512 | atomic_long_inc(v: &nfs_active_delegations); |
513 | |
514 | trace_nfs4_set_delegation(inode, fmode: type); |
515 | out: |
516 | spin_unlock(lock: &clp->cl_lock); |
517 | if (delegation != NULL) |
518 | __nfs_free_delegation(delegation); |
519 | if (freeme != NULL) { |
520 | nfs_do_return_delegation(inode, delegation: freeme, issync: 0); |
521 | nfs_free_delegation(delegation: freeme); |
522 | } |
523 | return status; |
524 | } |
525 | |
526 | /* |
527 | * Basic procedure for returning a delegation to the server |
528 | */ |
529 | static int nfs_end_delegation_return(struct inode *inode, struct nfs_delegation *delegation, int issync) |
530 | { |
531 | struct nfs_client *clp = NFS_SERVER(inode)->nfs_client; |
532 | unsigned int mode = O_WRONLY | O_RDWR; |
533 | int err = 0; |
534 | |
535 | if (delegation == NULL) |
536 | return 0; |
537 | |
538 | if (!issync) |
539 | mode |= O_NONBLOCK; |
540 | /* Recall of any remaining application leases */ |
541 | err = break_lease(inode, mode); |
542 | |
543 | while (err == 0) { |
544 | if (test_bit(NFS_DELEGATION_REVOKED, &delegation->flags)) |
545 | break; |
546 | err = nfs_delegation_claim_opens(inode, stateid: &delegation->stateid, |
547 | type: delegation->type); |
548 | if (!issync || err != -EAGAIN) |
549 | break; |
550 | /* |
551 | * Guard against state recovery |
552 | */ |
553 | err = nfs4_wait_clnt_recover(clp); |
554 | } |
555 | |
556 | if (err) { |
557 | nfs_abort_delegation_return(delegation, clp, err); |
558 | goto out; |
559 | } |
560 | |
561 | err = nfs_do_return_delegation(inode, delegation, issync); |
562 | out: |
563 | /* Refcount matched in nfs_start_delegation_return_locked() */ |
564 | nfs_put_delegation(delegation); |
565 | return err; |
566 | } |
567 | |
568 | static bool nfs_delegation_need_return(struct nfs_delegation *delegation) |
569 | { |
570 | bool ret = false; |
571 | |
572 | if (test_and_clear_bit(nr: NFS_DELEGATION_RETURN, addr: &delegation->flags)) |
573 | ret = true; |
574 | else if (test_bit(NFS_DELEGATION_RETURN_IF_CLOSED, &delegation->flags)) { |
575 | struct inode *inode; |
576 | |
577 | spin_lock(lock: &delegation->lock); |
578 | inode = delegation->inode; |
579 | if (inode && list_empty(head: &NFS_I(inode)->open_files)) |
580 | ret = true; |
581 | spin_unlock(lock: &delegation->lock); |
582 | } |
583 | if (ret) |
584 | clear_bit(nr: NFS_DELEGATION_RETURN_IF_CLOSED, addr: &delegation->flags); |
585 | if (test_bit(NFS_DELEGATION_RETURNING, &delegation->flags) || |
586 | test_bit(NFS_DELEGATION_RETURN_DELAYED, &delegation->flags) || |
587 | test_bit(NFS_DELEGATION_REVOKED, &delegation->flags)) |
588 | ret = false; |
589 | |
590 | return ret; |
591 | } |
592 | |
593 | static int nfs_server_return_marked_delegations(struct nfs_server *server, |
594 | void __always_unused *data) |
595 | { |
596 | struct nfs_delegation *delegation; |
597 | struct nfs_delegation *prev; |
598 | struct inode *inode; |
599 | struct inode *place_holder = NULL; |
600 | struct nfs_delegation *place_holder_deleg = NULL; |
601 | int err = 0; |
602 | |
603 | restart: |
604 | /* |
605 | * To avoid quadratic looping we hold a reference |
606 | * to an inode place_holder. Each time we restart, we |
607 | * list delegation in the server from the delegations |
608 | * of that inode. |
609 | * prev is an RCU-protected pointer to a delegation which |
610 | * wasn't marked for return and might be a good choice for |
611 | * the next place_holder. |
612 | */ |
613 | prev = NULL; |
614 | delegation = NULL; |
615 | rcu_read_lock(); |
616 | if (place_holder) |
617 | delegation = rcu_dereference(NFS_I(place_holder)->delegation); |
618 | if (!delegation || delegation != place_holder_deleg) |
619 | delegation = list_entry_rcu(server->delegations.next, |
620 | struct nfs_delegation, super_list); |
621 | list_for_each_entry_from_rcu(delegation, &server->delegations, super_list) { |
622 | struct inode *to_put = NULL; |
623 | |
624 | if (test_bit(NFS_DELEGATION_INODE_FREEING, &delegation->flags)) |
625 | continue; |
626 | if (!nfs_delegation_need_return(delegation)) { |
627 | if (nfs4_is_valid_delegation(delegation, flags: 0)) |
628 | prev = delegation; |
629 | continue; |
630 | } |
631 | |
632 | if (prev) { |
633 | struct inode *tmp = nfs_delegation_grab_inode(delegation: prev); |
634 | if (tmp) { |
635 | to_put = place_holder; |
636 | place_holder = tmp; |
637 | place_holder_deleg = prev; |
638 | } |
639 | } |
640 | |
641 | inode = nfs_delegation_grab_inode(delegation); |
642 | if (inode == NULL) { |
643 | rcu_read_unlock(); |
644 | iput(to_put); |
645 | goto restart; |
646 | } |
647 | delegation = nfs_start_delegation_return_locked(nfsi: NFS_I(inode)); |
648 | rcu_read_unlock(); |
649 | |
650 | iput(to_put); |
651 | |
652 | err = nfs_end_delegation_return(inode, delegation, issync: 0); |
653 | iput(inode); |
654 | cond_resched(); |
655 | if (!err) |
656 | goto restart; |
657 | set_bit(nr: NFS4CLNT_DELEGRETURN, addr: &server->nfs_client->cl_state); |
658 | goto out; |
659 | } |
660 | rcu_read_unlock(); |
661 | out: |
662 | iput(place_holder); |
663 | return err; |
664 | } |
665 | |
666 | static bool nfs_server_clear_delayed_delegations(struct nfs_server *server) |
667 | { |
668 | struct nfs_delegation *d; |
669 | bool ret = false; |
670 | |
671 | list_for_each_entry_rcu (d, &server->delegations, super_list) { |
672 | if (!test_bit(NFS_DELEGATION_RETURN_DELAYED, &d->flags)) |
673 | continue; |
674 | nfs_mark_return_delegation(server, delegation: d); |
675 | clear_bit(nr: NFS_DELEGATION_RETURN_DELAYED, addr: &d->flags); |
676 | ret = true; |
677 | } |
678 | return ret; |
679 | } |
680 | |
681 | static bool nfs_client_clear_delayed_delegations(struct nfs_client *clp) |
682 | { |
683 | struct nfs_server *server; |
684 | bool ret = false; |
685 | |
686 | if (!test_and_clear_bit(nr: NFS4CLNT_DELEGRETURN_DELAYED, addr: &clp->cl_state)) |
687 | goto out; |
688 | rcu_read_lock(); |
689 | list_for_each_entry_rcu (server, &clp->cl_superblocks, client_link) { |
690 | if (nfs_server_clear_delayed_delegations(server)) |
691 | ret = true; |
692 | } |
693 | rcu_read_unlock(); |
694 | out: |
695 | return ret; |
696 | } |
697 | |
698 | /** |
699 | * nfs_client_return_marked_delegations - return previously marked delegations |
700 | * @clp: nfs_client to process |
701 | * |
702 | * Note that this function is designed to be called by the state |
703 | * manager thread. For this reason, it cannot flush the dirty data, |
704 | * since that could deadlock in case of a state recovery error. |
705 | * |
706 | * Returns zero on success, or a negative errno value. |
707 | */ |
708 | int nfs_client_return_marked_delegations(struct nfs_client *clp) |
709 | { |
710 | int err = nfs_client_for_each_server( |
711 | clp, fn: nfs_server_return_marked_delegations, NULL); |
712 | if (err) |
713 | return err; |
714 | /* If a return was delayed, sleep to prevent hard looping */ |
715 | if (nfs_client_clear_delayed_delegations(clp)) |
716 | ssleep(seconds: 1); |
717 | return 0; |
718 | } |
719 | |
720 | /** |
721 | * nfs_inode_evict_delegation - return delegation, don't reclaim opens |
722 | * @inode: inode to process |
723 | * |
724 | * Does not protect against delegation reclaims, therefore really only safe |
725 | * to be called from nfs4_clear_inode(). Guaranteed to always free |
726 | * the delegation structure. |
727 | */ |
728 | void nfs_inode_evict_delegation(struct inode *inode) |
729 | { |
730 | struct nfs_delegation *delegation; |
731 | |
732 | delegation = nfs_inode_detach_delegation(inode); |
733 | if (delegation != NULL) { |
734 | set_bit(nr: NFS_DELEGATION_RETURNING, addr: &delegation->flags); |
735 | set_bit(nr: NFS_DELEGATION_INODE_FREEING, addr: &delegation->flags); |
736 | nfs_do_return_delegation(inode, delegation, issync: 1); |
737 | nfs_free_delegation(delegation); |
738 | } |
739 | } |
740 | |
741 | /** |
742 | * nfs4_inode_return_delegation - synchronously return a delegation |
743 | * @inode: inode to process |
744 | * |
745 | * This routine will always flush any dirty data to disk on the |
746 | * assumption that if we need to return the delegation, then |
747 | * we should stop caching. |
748 | * |
749 | * Returns zero on success, or a negative errno value. |
750 | */ |
751 | int nfs4_inode_return_delegation(struct inode *inode) |
752 | { |
753 | struct nfs_inode *nfsi = NFS_I(inode); |
754 | struct nfs_delegation *delegation; |
755 | |
756 | delegation = nfs_start_delegation_return(nfsi); |
757 | if (delegation != NULL) { |
758 | /* Synchronous recall of any application leases */ |
759 | break_lease(inode, O_WRONLY | O_RDWR); |
760 | if (S_ISREG(inode->i_mode)) |
761 | nfs_wb_all(inode); |
762 | return nfs_end_delegation_return(inode, delegation, issync: 1); |
763 | } |
764 | return 0; |
765 | } |
766 | |
767 | /** |
768 | * nfs4_inode_return_delegation_on_close - asynchronously return a delegation |
769 | * @inode: inode to process |
770 | * |
771 | * This routine is called on file close in order to determine if the |
772 | * inode delegation needs to be returned immediately. |
773 | */ |
774 | void nfs4_inode_return_delegation_on_close(struct inode *inode) |
775 | { |
776 | struct nfs_delegation *delegation; |
777 | struct nfs_delegation *ret = NULL; |
778 | |
779 | if (!inode) |
780 | return; |
781 | rcu_read_lock(); |
782 | delegation = nfs4_get_valid_delegation(inode); |
783 | if (!delegation) |
784 | goto out; |
785 | if (test_bit(NFS_DELEGATION_RETURN_IF_CLOSED, &delegation->flags) || |
786 | atomic_long_read(v: &nfs_active_delegations) >= nfs_delegation_watermark) { |
787 | spin_lock(lock: &delegation->lock); |
788 | if (delegation->inode && |
789 | list_empty(head: &NFS_I(inode)->open_files) && |
790 | !test_and_set_bit(nr: NFS_DELEGATION_RETURNING, addr: &delegation->flags)) { |
791 | clear_bit(nr: NFS_DELEGATION_RETURN_IF_CLOSED, addr: &delegation->flags); |
792 | /* Refcount matched in nfs_end_delegation_return() */ |
793 | ret = nfs_get_delegation(delegation); |
794 | } |
795 | spin_unlock(lock: &delegation->lock); |
796 | if (ret) |
797 | nfs_clear_verifier_delegated(inode); |
798 | } |
799 | out: |
800 | rcu_read_unlock(); |
801 | nfs_end_delegation_return(inode, delegation: ret, issync: 0); |
802 | } |
803 | |
804 | /** |
805 | * nfs4_inode_make_writeable |
806 | * @inode: pointer to inode |
807 | * |
808 | * Make the inode writeable by returning the delegation if necessary |
809 | * |
810 | * Returns zero on success, or a negative errno value. |
811 | */ |
812 | int nfs4_inode_make_writeable(struct inode *inode) |
813 | { |
814 | struct nfs_delegation *delegation; |
815 | |
816 | rcu_read_lock(); |
817 | delegation = nfs4_get_valid_delegation(inode); |
818 | if (delegation == NULL || |
819 | (nfs4_has_session(clp: NFS_SERVER(inode)->nfs_client) && |
820 | (delegation->type & FMODE_WRITE))) { |
821 | rcu_read_unlock(); |
822 | return 0; |
823 | } |
824 | rcu_read_unlock(); |
825 | return nfs4_inode_return_delegation(inode); |
826 | } |
827 | |
828 | static void nfs_mark_return_if_closed_delegation(struct nfs_server *server, |
829 | struct nfs_delegation *delegation) |
830 | { |
831 | set_bit(nr: NFS_DELEGATION_RETURN_IF_CLOSED, addr: &delegation->flags); |
832 | set_bit(nr: NFS4CLNT_DELEGRETURN, addr: &server->nfs_client->cl_state); |
833 | } |
834 | |
835 | static bool nfs_server_mark_return_all_delegations(struct nfs_server *server) |
836 | { |
837 | struct nfs_delegation *delegation; |
838 | bool ret = false; |
839 | |
840 | list_for_each_entry_rcu(delegation, &server->delegations, super_list) { |
841 | nfs_mark_return_delegation(server, delegation); |
842 | ret = true; |
843 | } |
844 | return ret; |
845 | } |
846 | |
847 | static void nfs_client_mark_return_all_delegations(struct nfs_client *clp) |
848 | { |
849 | struct nfs_server *server; |
850 | |
851 | rcu_read_lock(); |
852 | list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) |
853 | nfs_server_mark_return_all_delegations(server); |
854 | rcu_read_unlock(); |
855 | } |
856 | |
857 | static void nfs_delegation_run_state_manager(struct nfs_client *clp) |
858 | { |
859 | if (test_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state)) |
860 | nfs4_schedule_state_manager(clp); |
861 | } |
862 | |
863 | /** |
864 | * nfs_expire_all_delegations |
865 | * @clp: client to process |
866 | * |
867 | */ |
868 | void nfs_expire_all_delegations(struct nfs_client *clp) |
869 | { |
870 | nfs_client_mark_return_all_delegations(clp); |
871 | nfs_delegation_run_state_manager(clp); |
872 | } |
873 | |
874 | /** |
875 | * nfs_server_return_all_delegations - return delegations for one superblock |
876 | * @server: pointer to nfs_server to process |
877 | * |
878 | */ |
879 | void nfs_server_return_all_delegations(struct nfs_server *server) |
880 | { |
881 | struct nfs_client *clp = server->nfs_client; |
882 | bool need_wait; |
883 | |
884 | if (clp == NULL) |
885 | return; |
886 | |
887 | rcu_read_lock(); |
888 | need_wait = nfs_server_mark_return_all_delegations(server); |
889 | rcu_read_unlock(); |
890 | |
891 | if (need_wait) { |
892 | nfs4_schedule_state_manager(clp); |
893 | nfs4_wait_clnt_recover(clp); |
894 | } |
895 | } |
896 | |
897 | static void nfs_mark_return_unused_delegation_types(struct nfs_server *server, |
898 | fmode_t flags) |
899 | { |
900 | struct nfs_delegation *delegation; |
901 | |
902 | list_for_each_entry_rcu(delegation, &server->delegations, super_list) { |
903 | if ((delegation->type == (FMODE_READ|FMODE_WRITE)) && !(flags & FMODE_WRITE)) |
904 | continue; |
905 | if (delegation->type & flags) |
906 | nfs_mark_return_if_closed_delegation(server, delegation); |
907 | } |
908 | } |
909 | |
910 | static void nfs_client_mark_return_unused_delegation_types(struct nfs_client *clp, |
911 | fmode_t flags) |
912 | { |
913 | struct nfs_server *server; |
914 | |
915 | rcu_read_lock(); |
916 | list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) |
917 | nfs_mark_return_unused_delegation_types(server, flags); |
918 | rcu_read_unlock(); |
919 | } |
920 | |
921 | static void nfs_revoke_delegation(struct inode *inode, |
922 | const nfs4_stateid *stateid) |
923 | { |
924 | struct nfs_delegation *delegation; |
925 | nfs4_stateid tmp; |
926 | bool ret = false; |
927 | |
928 | rcu_read_lock(); |
929 | delegation = rcu_dereference(NFS_I(inode)->delegation); |
930 | if (delegation == NULL) |
931 | goto out; |
932 | if (stateid == NULL) { |
933 | nfs4_stateid_copy(dst: &tmp, src: &delegation->stateid); |
934 | stateid = &tmp; |
935 | } else { |
936 | if (!nfs4_stateid_match_other(dst: stateid, src: &delegation->stateid)) |
937 | goto out; |
938 | spin_lock(lock: &delegation->lock); |
939 | if (stateid->seqid) { |
940 | if (nfs4_stateid_is_newer(s1: &delegation->stateid, s2: stateid)) { |
941 | spin_unlock(lock: &delegation->lock); |
942 | goto out; |
943 | } |
944 | delegation->stateid.seqid = stateid->seqid; |
945 | } |
946 | spin_unlock(lock: &delegation->lock); |
947 | } |
948 | nfs_mark_delegation_revoked(delegation); |
949 | ret = true; |
950 | out: |
951 | rcu_read_unlock(); |
952 | if (ret) |
953 | nfs_inode_find_state_and_recover(inode, stateid); |
954 | } |
955 | |
956 | void nfs_remove_bad_delegation(struct inode *inode, |
957 | const nfs4_stateid *stateid) |
958 | { |
959 | nfs_revoke_delegation(inode, stateid); |
960 | } |
961 | EXPORT_SYMBOL_GPL(nfs_remove_bad_delegation); |
962 | |
963 | void nfs_delegation_mark_returned(struct inode *inode, |
964 | const nfs4_stateid *stateid) |
965 | { |
966 | struct nfs_delegation *delegation; |
967 | |
968 | if (!inode) |
969 | return; |
970 | |
971 | rcu_read_lock(); |
972 | delegation = rcu_dereference(NFS_I(inode)->delegation); |
973 | if (!delegation) |
974 | goto out_rcu_unlock; |
975 | |
976 | spin_lock(lock: &delegation->lock); |
977 | if (!nfs4_stateid_match_other(dst: stateid, src: &delegation->stateid)) |
978 | goto out_spin_unlock; |
979 | if (stateid->seqid) { |
980 | /* If delegation->stateid is newer, dont mark as returned */ |
981 | if (nfs4_stateid_is_newer(s1: &delegation->stateid, s2: stateid)) |
982 | goto out_clear_returning; |
983 | if (delegation->stateid.seqid != stateid->seqid) |
984 | delegation->stateid.seqid = stateid->seqid; |
985 | } |
986 | |
987 | nfs_mark_delegation_revoked(delegation); |
988 | |
989 | out_clear_returning: |
990 | clear_bit(nr: NFS_DELEGATION_RETURNING, addr: &delegation->flags); |
991 | out_spin_unlock: |
992 | spin_unlock(lock: &delegation->lock); |
993 | out_rcu_unlock: |
994 | rcu_read_unlock(); |
995 | |
996 | nfs_inode_find_state_and_recover(inode, stateid); |
997 | } |
998 | |
999 | /** |
1000 | * nfs_expire_unused_delegation_types |
1001 | * @clp: client to process |
1002 | * @flags: delegation types to expire |
1003 | * |
1004 | */ |
1005 | void nfs_expire_unused_delegation_types(struct nfs_client *clp, fmode_t flags) |
1006 | { |
1007 | nfs_client_mark_return_unused_delegation_types(clp, flags); |
1008 | nfs_delegation_run_state_manager(clp); |
1009 | } |
1010 | |
1011 | static void nfs_mark_return_unreferenced_delegations(struct nfs_server *server) |
1012 | { |
1013 | struct nfs_delegation *delegation; |
1014 | |
1015 | list_for_each_entry_rcu(delegation, &server->delegations, super_list) { |
1016 | if (test_and_clear_bit(nr: NFS_DELEGATION_REFERENCED, addr: &delegation->flags)) |
1017 | continue; |
1018 | nfs_mark_return_if_closed_delegation(server, delegation); |
1019 | } |
1020 | } |
1021 | |
1022 | /** |
1023 | * nfs_expire_unreferenced_delegations - Eliminate unused delegations |
1024 | * @clp: nfs_client to process |
1025 | * |
1026 | */ |
1027 | void nfs_expire_unreferenced_delegations(struct nfs_client *clp) |
1028 | { |
1029 | struct nfs_server *server; |
1030 | |
1031 | rcu_read_lock(); |
1032 | list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) |
1033 | nfs_mark_return_unreferenced_delegations(server); |
1034 | rcu_read_unlock(); |
1035 | |
1036 | nfs_delegation_run_state_manager(clp); |
1037 | } |
1038 | |
1039 | /** |
1040 | * nfs_async_inode_return_delegation - asynchronously return a delegation |
1041 | * @inode: inode to process |
1042 | * @stateid: state ID information |
1043 | * |
1044 | * Returns zero on success, or a negative errno value. |
1045 | */ |
1046 | int nfs_async_inode_return_delegation(struct inode *inode, |
1047 | const nfs4_stateid *stateid) |
1048 | { |
1049 | struct nfs_server *server = NFS_SERVER(inode); |
1050 | struct nfs_client *clp = server->nfs_client; |
1051 | struct nfs_delegation *delegation; |
1052 | |
1053 | rcu_read_lock(); |
1054 | delegation = nfs4_get_valid_delegation(inode); |
1055 | if (delegation == NULL) |
1056 | goto out_enoent; |
1057 | if (stateid != NULL && |
1058 | !clp->cl_mvops->match_stateid(&delegation->stateid, stateid)) |
1059 | goto out_enoent; |
1060 | nfs_mark_return_delegation(server, delegation); |
1061 | rcu_read_unlock(); |
1062 | |
1063 | /* If there are any application leases or delegations, recall them */ |
1064 | break_lease(inode, O_WRONLY | O_RDWR | O_NONBLOCK); |
1065 | |
1066 | nfs_delegation_run_state_manager(clp); |
1067 | return 0; |
1068 | out_enoent: |
1069 | rcu_read_unlock(); |
1070 | return -ENOENT; |
1071 | } |
1072 | |
1073 | static struct inode * |
1074 | nfs_delegation_find_inode_server(struct nfs_server *server, |
1075 | const struct nfs_fh *fhandle) |
1076 | { |
1077 | struct nfs_delegation *delegation; |
1078 | struct super_block *freeme = NULL; |
1079 | struct inode *res = NULL; |
1080 | |
1081 | list_for_each_entry_rcu(delegation, &server->delegations, super_list) { |
1082 | spin_lock(lock: &delegation->lock); |
1083 | if (delegation->inode != NULL && |
1084 | !test_bit(NFS_DELEGATION_REVOKED, &delegation->flags) && |
1085 | nfs_compare_fh(a: fhandle, b: &NFS_I(inode: delegation->inode)->fh) == 0) { |
1086 | if (nfs_sb_active(sb: server->super)) { |
1087 | freeme = server->super; |
1088 | res = igrab(delegation->inode); |
1089 | } |
1090 | spin_unlock(lock: &delegation->lock); |
1091 | if (res != NULL) |
1092 | return res; |
1093 | if (freeme) { |
1094 | rcu_read_unlock(); |
1095 | nfs_sb_deactive(sb: freeme); |
1096 | rcu_read_lock(); |
1097 | } |
1098 | return ERR_PTR(error: -EAGAIN); |
1099 | } |
1100 | spin_unlock(lock: &delegation->lock); |
1101 | } |
1102 | return ERR_PTR(error: -ENOENT); |
1103 | } |
1104 | |
1105 | /** |
1106 | * nfs_delegation_find_inode - retrieve the inode associated with a delegation |
1107 | * @clp: client state handle |
1108 | * @fhandle: filehandle from a delegation recall |
1109 | * |
1110 | * Returns pointer to inode matching "fhandle," or NULL if a matching inode |
1111 | * cannot be found. |
1112 | */ |
1113 | struct inode *nfs_delegation_find_inode(struct nfs_client *clp, |
1114 | const struct nfs_fh *fhandle) |
1115 | { |
1116 | struct nfs_server *server; |
1117 | struct inode *res; |
1118 | |
1119 | rcu_read_lock(); |
1120 | list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) { |
1121 | res = nfs_delegation_find_inode_server(server, fhandle); |
1122 | if (res != ERR_PTR(error: -ENOENT)) { |
1123 | rcu_read_unlock(); |
1124 | return res; |
1125 | } |
1126 | } |
1127 | rcu_read_unlock(); |
1128 | return ERR_PTR(error: -ENOENT); |
1129 | } |
1130 | |
1131 | static void nfs_delegation_mark_reclaim_server(struct nfs_server *server) |
1132 | { |
1133 | struct nfs_delegation *delegation; |
1134 | |
1135 | list_for_each_entry_rcu(delegation, &server->delegations, super_list) { |
1136 | /* |
1137 | * If the delegation may have been admin revoked, then we |
1138 | * cannot reclaim it. |
1139 | */ |
1140 | if (test_bit(NFS_DELEGATION_TEST_EXPIRED, &delegation->flags)) |
1141 | continue; |
1142 | set_bit(nr: NFS_DELEGATION_NEED_RECLAIM, addr: &delegation->flags); |
1143 | } |
1144 | } |
1145 | |
1146 | /** |
1147 | * nfs_delegation_mark_reclaim - mark all delegations as needing to be reclaimed |
1148 | * @clp: nfs_client to process |
1149 | * |
1150 | */ |
1151 | void nfs_delegation_mark_reclaim(struct nfs_client *clp) |
1152 | { |
1153 | struct nfs_server *server; |
1154 | |
1155 | rcu_read_lock(); |
1156 | list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) |
1157 | nfs_delegation_mark_reclaim_server(server); |
1158 | rcu_read_unlock(); |
1159 | } |
1160 | |
1161 | static int nfs_server_reap_unclaimed_delegations(struct nfs_server *server, |
1162 | void __always_unused *data) |
1163 | { |
1164 | struct nfs_delegation *delegation; |
1165 | struct inode *inode; |
1166 | restart: |
1167 | rcu_read_lock(); |
1168 | restart_locked: |
1169 | list_for_each_entry_rcu(delegation, &server->delegations, super_list) { |
1170 | if (test_bit(NFS_DELEGATION_INODE_FREEING, |
1171 | &delegation->flags) || |
1172 | test_bit(NFS_DELEGATION_RETURNING, |
1173 | &delegation->flags) || |
1174 | test_bit(NFS_DELEGATION_NEED_RECLAIM, |
1175 | &delegation->flags) == 0) |
1176 | continue; |
1177 | inode = nfs_delegation_grab_inode(delegation); |
1178 | if (inode == NULL) |
1179 | goto restart_locked; |
1180 | delegation = nfs_start_delegation_return_locked(nfsi: NFS_I(inode)); |
1181 | rcu_read_unlock(); |
1182 | if (delegation != NULL) { |
1183 | if (nfs_detach_delegation(nfsi: NFS_I(inode), delegation, |
1184 | server) != NULL) |
1185 | nfs_free_delegation(delegation); |
1186 | /* Match nfs_start_delegation_return_locked */ |
1187 | nfs_put_delegation(delegation); |
1188 | } |
1189 | iput(inode); |
1190 | cond_resched(); |
1191 | goto restart; |
1192 | } |
1193 | rcu_read_unlock(); |
1194 | return 0; |
1195 | } |
1196 | |
1197 | /** |
1198 | * nfs_delegation_reap_unclaimed - reap unclaimed delegations after reboot recovery is done |
1199 | * @clp: nfs_client to process |
1200 | * |
1201 | */ |
1202 | void nfs_delegation_reap_unclaimed(struct nfs_client *clp) |
1203 | { |
1204 | nfs_client_for_each_server(clp, fn: nfs_server_reap_unclaimed_delegations, |
1205 | NULL); |
1206 | } |
1207 | |
1208 | static inline bool nfs4_server_rebooted(const struct nfs_client *clp) |
1209 | { |
1210 | return (clp->cl_state & (BIT(NFS4CLNT_CHECK_LEASE) | |
1211 | BIT(NFS4CLNT_LEASE_EXPIRED) | |
1212 | BIT(NFS4CLNT_SESSION_RESET))) != 0; |
1213 | } |
1214 | |
1215 | static void nfs_mark_test_expired_delegation(struct nfs_server *server, |
1216 | struct nfs_delegation *delegation) |
1217 | { |
1218 | if (delegation->stateid.type == NFS4_INVALID_STATEID_TYPE) |
1219 | return; |
1220 | clear_bit(nr: NFS_DELEGATION_NEED_RECLAIM, addr: &delegation->flags); |
1221 | set_bit(nr: NFS_DELEGATION_TEST_EXPIRED, addr: &delegation->flags); |
1222 | set_bit(nr: NFS4CLNT_DELEGATION_EXPIRED, addr: &server->nfs_client->cl_state); |
1223 | } |
1224 | |
1225 | static void nfs_inode_mark_test_expired_delegation(struct nfs_server *server, |
1226 | struct inode *inode) |
1227 | { |
1228 | struct nfs_delegation *delegation; |
1229 | |
1230 | rcu_read_lock(); |
1231 | delegation = rcu_dereference(NFS_I(inode)->delegation); |
1232 | if (delegation) |
1233 | nfs_mark_test_expired_delegation(server, delegation); |
1234 | rcu_read_unlock(); |
1235 | |
1236 | } |
1237 | |
1238 | static void nfs_delegation_mark_test_expired_server(struct nfs_server *server) |
1239 | { |
1240 | struct nfs_delegation *delegation; |
1241 | |
1242 | list_for_each_entry_rcu(delegation, &server->delegations, super_list) |
1243 | nfs_mark_test_expired_delegation(server, delegation); |
1244 | } |
1245 | |
1246 | /** |
1247 | * nfs_mark_test_expired_all_delegations - mark all delegations for testing |
1248 | * @clp: nfs_client to process |
1249 | * |
1250 | * Iterates through all the delegations associated with this server and |
1251 | * marks them as needing to be checked for validity. |
1252 | */ |
1253 | void nfs_mark_test_expired_all_delegations(struct nfs_client *clp) |
1254 | { |
1255 | struct nfs_server *server; |
1256 | |
1257 | rcu_read_lock(); |
1258 | list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) |
1259 | nfs_delegation_mark_test_expired_server(server); |
1260 | rcu_read_unlock(); |
1261 | } |
1262 | |
1263 | /** |
1264 | * nfs_test_expired_all_delegations - test all delegations for a client |
1265 | * @clp: nfs_client to process |
1266 | * |
1267 | * Helper for handling "recallable state revoked" status from server. |
1268 | */ |
1269 | void nfs_test_expired_all_delegations(struct nfs_client *clp) |
1270 | { |
1271 | nfs_mark_test_expired_all_delegations(clp); |
1272 | nfs4_schedule_state_manager(clp); |
1273 | } |
1274 | |
1275 | static void |
1276 | nfs_delegation_test_free_expired(struct inode *inode, |
1277 | nfs4_stateid *stateid, |
1278 | const struct cred *cred) |
1279 | { |
1280 | struct nfs_server *server = NFS_SERVER(inode); |
1281 | const struct nfs4_minor_version_ops *ops = server->nfs_client->cl_mvops; |
1282 | int status; |
1283 | |
1284 | if (!cred) |
1285 | return; |
1286 | status = ops->test_and_free_expired(server, stateid, cred); |
1287 | if (status == -NFS4ERR_EXPIRED || status == -NFS4ERR_BAD_STATEID) |
1288 | nfs_remove_bad_delegation(inode, stateid); |
1289 | } |
1290 | |
1291 | static int nfs_server_reap_expired_delegations(struct nfs_server *server, |
1292 | void __always_unused *data) |
1293 | { |
1294 | struct nfs_delegation *delegation; |
1295 | struct inode *inode; |
1296 | const struct cred *cred; |
1297 | nfs4_stateid stateid; |
1298 | unsigned long gen = ++server->delegation_gen; |
1299 | |
1300 | restart: |
1301 | rcu_read_lock(); |
1302 | restart_locked: |
1303 | list_for_each_entry_rcu(delegation, &server->delegations, super_list) { |
1304 | if (test_bit(NFS_DELEGATION_INODE_FREEING, |
1305 | &delegation->flags) || |
1306 | test_bit(NFS_DELEGATION_RETURNING, |
1307 | &delegation->flags) || |
1308 | test_bit(NFS_DELEGATION_TEST_EXPIRED, |
1309 | &delegation->flags) == 0 || |
1310 | delegation->test_gen == gen) |
1311 | continue; |
1312 | inode = nfs_delegation_grab_inode(delegation); |
1313 | if (inode == NULL) |
1314 | goto restart_locked; |
1315 | spin_lock(lock: &delegation->lock); |
1316 | cred = get_cred_rcu(cred: delegation->cred); |
1317 | nfs4_stateid_copy(dst: &stateid, src: &delegation->stateid); |
1318 | spin_unlock(lock: &delegation->lock); |
1319 | delegation->test_gen = gen; |
1320 | clear_bit(nr: NFS_DELEGATION_TEST_EXPIRED, addr: &delegation->flags); |
1321 | rcu_read_unlock(); |
1322 | nfs_delegation_test_free_expired(inode, stateid: &stateid, cred); |
1323 | put_cred(cred); |
1324 | if (!nfs4_server_rebooted(clp: server->nfs_client)) { |
1325 | iput(inode); |
1326 | cond_resched(); |
1327 | goto restart; |
1328 | } |
1329 | nfs_inode_mark_test_expired_delegation(server,inode); |
1330 | iput(inode); |
1331 | return -EAGAIN; |
1332 | } |
1333 | rcu_read_unlock(); |
1334 | return 0; |
1335 | } |
1336 | |
1337 | /** |
1338 | * nfs_reap_expired_delegations - reap expired delegations |
1339 | * @clp: nfs_client to process |
1340 | * |
1341 | * Iterates through all the delegations associated with this server and |
1342 | * checks if they have may have been revoked. This function is usually |
1343 | * expected to be called in cases where the server may have lost its |
1344 | * lease. |
1345 | */ |
1346 | void nfs_reap_expired_delegations(struct nfs_client *clp) |
1347 | { |
1348 | nfs_client_for_each_server(clp, fn: nfs_server_reap_expired_delegations, |
1349 | NULL); |
1350 | } |
1351 | |
1352 | void nfs_inode_find_delegation_state_and_recover(struct inode *inode, |
1353 | const nfs4_stateid *stateid) |
1354 | { |
1355 | struct nfs_client *clp = NFS_SERVER(inode)->nfs_client; |
1356 | struct nfs_delegation *delegation; |
1357 | bool found = false; |
1358 | |
1359 | rcu_read_lock(); |
1360 | delegation = rcu_dereference(NFS_I(inode)->delegation); |
1361 | if (delegation && |
1362 | nfs4_stateid_match_or_older(dst: &delegation->stateid, src: stateid) && |
1363 | !test_bit(NFS_DELEGATION_REVOKED, &delegation->flags)) { |
1364 | nfs_mark_test_expired_delegation(server: NFS_SERVER(inode), delegation); |
1365 | found = true; |
1366 | } |
1367 | rcu_read_unlock(); |
1368 | if (found) |
1369 | nfs4_schedule_state_manager(clp); |
1370 | } |
1371 | |
1372 | /** |
1373 | * nfs_delegations_present - check for existence of delegations |
1374 | * @clp: client state handle |
1375 | * |
1376 | * Returns one if there are any nfs_delegation structures attached |
1377 | * to this nfs_client. |
1378 | */ |
1379 | int nfs_delegations_present(struct nfs_client *clp) |
1380 | { |
1381 | struct nfs_server *server; |
1382 | int ret = 0; |
1383 | |
1384 | rcu_read_lock(); |
1385 | list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) |
1386 | if (!list_empty(head: &server->delegations)) { |
1387 | ret = 1; |
1388 | break; |
1389 | } |
1390 | rcu_read_unlock(); |
1391 | return ret; |
1392 | } |
1393 | |
1394 | /** |
1395 | * nfs4_refresh_delegation_stateid - Update delegation stateid seqid |
1396 | * @dst: stateid to refresh |
1397 | * @inode: inode to check |
1398 | * |
1399 | * Returns "true" and updates "dst->seqid" * if inode had a delegation |
1400 | * that matches our delegation stateid. Otherwise "false" is returned. |
1401 | */ |
1402 | bool nfs4_refresh_delegation_stateid(nfs4_stateid *dst, struct inode *inode) |
1403 | { |
1404 | struct nfs_delegation *delegation; |
1405 | bool ret = false; |
1406 | if (!inode) |
1407 | goto out; |
1408 | |
1409 | rcu_read_lock(); |
1410 | delegation = rcu_dereference(NFS_I(inode)->delegation); |
1411 | if (delegation != NULL && |
1412 | nfs4_stateid_match_other(dst, src: &delegation->stateid) && |
1413 | nfs4_stateid_is_newer(s1: &delegation->stateid, s2: dst) && |
1414 | !test_bit(NFS_DELEGATION_REVOKED, &delegation->flags)) { |
1415 | dst->seqid = delegation->stateid.seqid; |
1416 | ret = true; |
1417 | } |
1418 | rcu_read_unlock(); |
1419 | out: |
1420 | return ret; |
1421 | } |
1422 | |
1423 | /** |
1424 | * nfs4_copy_delegation_stateid - Copy inode's state ID information |
1425 | * @inode: inode to check |
1426 | * @flags: delegation type requirement |
1427 | * @dst: stateid data structure to fill in |
1428 | * @cred: optional argument to retrieve credential |
1429 | * |
1430 | * Returns "true" and fills in "dst->data" * if inode had a delegation, |
1431 | * otherwise "false" is returned. |
1432 | */ |
1433 | bool nfs4_copy_delegation_stateid(struct inode *inode, fmode_t flags, |
1434 | nfs4_stateid *dst, const struct cred **cred) |
1435 | { |
1436 | struct nfs_inode *nfsi = NFS_I(inode); |
1437 | struct nfs_delegation *delegation; |
1438 | bool ret = false; |
1439 | |
1440 | flags &= FMODE_READ|FMODE_WRITE; |
1441 | rcu_read_lock(); |
1442 | delegation = rcu_dereference(nfsi->delegation); |
1443 | if (!delegation) |
1444 | goto out; |
1445 | spin_lock(lock: &delegation->lock); |
1446 | ret = nfs4_is_valid_delegation(delegation, flags); |
1447 | if (ret) { |
1448 | nfs4_stateid_copy(dst, src: &delegation->stateid); |
1449 | nfs_mark_delegation_referenced(delegation); |
1450 | if (cred) |
1451 | *cred = get_cred(cred: delegation->cred); |
1452 | } |
1453 | spin_unlock(lock: &delegation->lock); |
1454 | out: |
1455 | rcu_read_unlock(); |
1456 | return ret; |
1457 | } |
1458 | |
1459 | /** |
1460 | * nfs4_delegation_flush_on_close - Check if we must flush file on close |
1461 | * @inode: inode to check |
1462 | * |
1463 | * This function checks the number of outstanding writes to the file |
1464 | * against the delegation 'space_limit' field to see if |
1465 | * the spec requires us to flush the file on close. |
1466 | */ |
1467 | bool nfs4_delegation_flush_on_close(const struct inode *inode) |
1468 | { |
1469 | struct nfs_inode *nfsi = NFS_I(inode); |
1470 | struct nfs_delegation *delegation; |
1471 | bool ret = true; |
1472 | |
1473 | rcu_read_lock(); |
1474 | delegation = rcu_dereference(nfsi->delegation); |
1475 | if (delegation == NULL || !(delegation->type & FMODE_WRITE)) |
1476 | goto out; |
1477 | if (atomic_long_read(v: &nfsi->nrequests) < delegation->pagemod_limit) |
1478 | ret = false; |
1479 | out: |
1480 | rcu_read_unlock(); |
1481 | return ret; |
1482 | } |
1483 | |
1484 | module_param_named(delegation_watermark, nfs_delegation_watermark, uint, 0644); |
1485 | |