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