hc
2024-02-20 102a0743326a03cd1a1202ceda21e175b7d3575c
kernel/fs/nfs/delegation.c
....@@ -1,3 +1,4 @@
1
+// SPDX-License-Identifier: GPL-2.0-only
12 /*
23 * linux/fs/nfs/delegation.c
34 *
....@@ -24,13 +25,44 @@
2425 #include "internal.h"
2526 #include "nfs4trace.h"
2627
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(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(NFS_DELEGATION_REVOKED, &delegation->flags)) {
43
+ delegation->stateid.type = NFS4_INVALID_STATEID_TYPE;
44
+ atomic_long_dec(&nfs_active_delegations);
45
+ if (!test_bit(NFS_DELEGATION_RETURNING, &delegation->flags))
46
+ nfs_clear_verifier_delegated(delegation->inode);
47
+ }
48
+}
49
+
50
+static struct nfs_delegation *nfs_get_delegation(struct nfs_delegation *delegation)
51
+{
52
+ refcount_inc(&delegation->refcount);
53
+ return delegation;
54
+}
55
+
56
+static void nfs_put_delegation(struct nfs_delegation *delegation)
57
+{
58
+ if (refcount_dec_and_test(&delegation->refcount))
59
+ __nfs_free_delegation(delegation);
60
+}
61
+
2762 static void nfs_free_delegation(struct nfs_delegation *delegation)
2863 {
29
- if (delegation->cred) {
30
- put_rpccred(delegation->cred);
31
- delegation->cred = NULL;
32
- }
33
- kfree_rcu(delegation, rcu);
64
+ nfs_mark_delegation_revoked(delegation);
65
+ nfs_put_delegation(delegation);
3466 }
3567
3668 /**
....@@ -41,6 +73,13 @@
4173 void nfs_mark_delegation_referenced(struct nfs_delegation *delegation)
4274 {
4375 set_bit(NFS_DELEGATION_REFERENCED, &delegation->flags);
76
+}
77
+
78
+static void nfs_mark_return_delegation(struct nfs_server *server,
79
+ struct nfs_delegation *delegation)
80
+{
81
+ set_bit(NFS_DELEGATION_RETURN, &delegation->flags);
82
+ set_bit(NFS4CLNT_DELEGRETURN, &server->nfs_client->cl_state);
4483 }
4584
4685 static bool
....@@ -146,8 +185,8 @@
146185 int err;
147186
148187 again:
149
- spin_lock(&inode->i_lock);
150
- list_for_each_entry(ctx, &nfsi->open_files, list) {
188
+ rcu_read_lock();
189
+ list_for_each_entry_rcu(ctx, &nfsi->open_files, list) {
151190 state = ctx->state;
152191 if (state == NULL)
153192 continue;
....@@ -157,16 +196,17 @@
157196 continue;
158197 if (!nfs4_stateid_match(&state->stateid, stateid))
159198 continue;
160
- get_nfs_open_context(ctx);
161
- spin_unlock(&inode->i_lock);
199
+ if (!get_nfs_open_context(ctx))
200
+ continue;
201
+ rcu_read_unlock();
162202 sp = state->owner;
163203 /* Block nfs4_proc_unlck */
164204 mutex_lock(&sp->so_delegreturn_mutex);
165
- seq = read_seqbegin(&sp->so_reclaim_seqlock);
205
+ seq = raw_seqcount_begin(&sp->so_reclaim_seqcount);
166206 err = nfs4_open_delegation_recall(ctx, state, stateid);
167207 if (!err)
168208 err = nfs_delegation_claim_locks(state, stateid);
169
- if (!err && read_seqretry(&sp->so_reclaim_seqlock, seq))
209
+ if (!err && read_seqcount_retry(&sp->so_reclaim_seqcount, seq))
170210 err = -EAGAIN;
171211 mutex_unlock(&sp->so_delegreturn_mutex);
172212 put_nfs_open_context(ctx);
....@@ -174,7 +214,7 @@
174214 return err;
175215 goto again;
176216 }
177
- spin_unlock(&inode->i_lock);
217
+ rcu_read_unlock();
178218 return 0;
179219 }
180220
....@@ -187,49 +227,51 @@
187227 * @pagemod_limit: write delegation "space_limit"
188228 *
189229 */
190
-void nfs_inode_reclaim_delegation(struct inode *inode, struct rpc_cred *cred,
191
- fmode_t type,
192
- const nfs4_stateid *stateid,
230
+void nfs_inode_reclaim_delegation(struct inode *inode, const struct cred *cred,
231
+ fmode_t type, const nfs4_stateid *stateid,
193232 unsigned long pagemod_limit)
194233 {
195234 struct nfs_delegation *delegation;
196
- struct rpc_cred *oldcred = NULL;
235
+ const struct cred *oldcred = NULL;
197236
198237 rcu_read_lock();
199238 delegation = rcu_dereference(NFS_I(inode)->delegation);
200239 if (delegation != NULL) {
201240 spin_lock(&delegation->lock);
202
- if (delegation->inode != NULL) {
203
- nfs4_stateid_copy(&delegation->stateid, stateid);
204
- delegation->type = type;
205
- delegation->pagemod_limit = pagemod_limit;
206
- oldcred = delegation->cred;
207
- delegation->cred = get_rpccred(cred);
208
- clear_bit(NFS_DELEGATION_NEED_RECLAIM,
209
- &delegation->flags);
210
- spin_unlock(&delegation->lock);
211
- rcu_read_unlock();
212
- put_rpccred(oldcred);
213
- trace_nfs4_reclaim_delegation(inode, type);
214
- return;
215
- }
216
- /* We appear to have raced with a delegation return. */
241
+ nfs4_stateid_copy(&delegation->stateid, stateid);
242
+ delegation->type = type;
243
+ delegation->pagemod_limit = pagemod_limit;
244
+ oldcred = delegation->cred;
245
+ delegation->cred = get_cred(cred);
246
+ clear_bit(NFS_DELEGATION_NEED_RECLAIM, &delegation->flags);
247
+ if (test_and_clear_bit(NFS_DELEGATION_REVOKED,
248
+ &delegation->flags))
249
+ atomic_long_inc(&nfs_active_delegations);
217250 spin_unlock(&delegation->lock);
251
+ rcu_read_unlock();
252
+ put_cred(oldcred);
253
+ trace_nfs4_reclaim_delegation(inode, type);
254
+ } else {
255
+ rcu_read_unlock();
256
+ nfs_inode_set_delegation(inode, cred, type, stateid,
257
+ pagemod_limit);
218258 }
219
- rcu_read_unlock();
220
- nfs_inode_set_delegation(inode, cred, type, stateid, pagemod_limit);
221259 }
222260
223261 static int nfs_do_return_delegation(struct inode *inode, struct nfs_delegation *delegation, int issync)
224262 {
263
+ const struct cred *cred;
225264 int res = 0;
226265
227
- if (!test_bit(NFS_DELEGATION_REVOKED, &delegation->flags))
228
- res = nfs4_proc_delegreturn(inode,
229
- delegation->cred,
266
+ if (!test_bit(NFS_DELEGATION_REVOKED, &delegation->flags)) {
267
+ spin_lock(&delegation->lock);
268
+ cred = get_cred(delegation->cred);
269
+ spin_unlock(&delegation->lock);
270
+ res = nfs4_proc_delegreturn(inode, cred,
230271 &delegation->stateid,
231272 issync);
232
- nfs_free_delegation(delegation);
273
+ put_cred(cred);
274
+ }
233275 return res;
234276 }
235277
....@@ -255,9 +297,14 @@
255297 if (delegation == NULL)
256298 goto out;
257299 spin_lock(&delegation->lock);
258
- if (!test_and_set_bit(NFS_DELEGATION_RETURNING, &delegation->flags))
259
- ret = delegation;
300
+ if (!test_and_set_bit(NFS_DELEGATION_RETURNING, &delegation->flags)) {
301
+ clear_bit(NFS_DELEGATION_RETURN_DELAYED, &delegation->flags);
302
+ /* Refcount matched in nfs_end_delegation_return() */
303
+ ret = nfs_get_delegation(delegation);
304
+ }
260305 spin_unlock(&delegation->lock);
306
+ if (ret)
307
+ nfs_clear_verifier_delegated(&nfsi->vfs_inode);
261308 out:
262309 return ret;
263310 }
....@@ -273,16 +320,17 @@
273320 return delegation;
274321 }
275322
276
-static void
277
-nfs_abort_delegation_return(struct nfs_delegation *delegation,
278
- struct nfs_client *clp)
323
+static void nfs_abort_delegation_return(struct nfs_delegation *delegation,
324
+ struct nfs_client *clp, int err)
279325 {
280326
281327 spin_lock(&delegation->lock);
282328 clear_bit(NFS_DELEGATION_RETURNING, &delegation->flags);
283
- set_bit(NFS_DELEGATION_RETURN, &delegation->flags);
329
+ if (err == -EAGAIN) {
330
+ set_bit(NFS_DELEGATION_RETURN_DELAYED, &delegation->flags);
331
+ set_bit(NFS4CLNT_DELEGRETURN_DELAYED, &clp->cl_state);
332
+ }
284333 spin_unlock(&delegation->lock);
285
- set_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state);
286334 }
287335
288336 static struct nfs_delegation *
....@@ -298,7 +346,10 @@
298346 return NULL;
299347
300348 spin_lock(&delegation->lock);
301
- set_bit(NFS_DELEGATION_RETURNING, &delegation->flags);
349
+ if (!delegation->inode) {
350
+ spin_unlock(&delegation->lock);
351
+ return NULL;
352
+ }
302353 list_del_rcu(&delegation->super_list);
303354 delegation->inode = NULL;
304355 rcu_assign_pointer(nfsi->delegation, NULL);
....@@ -325,10 +376,24 @@
325376 struct nfs_server *server = NFS_SERVER(inode);
326377 struct nfs_delegation *delegation;
327378
328
- delegation = nfs_start_delegation_return(nfsi);
329
- if (delegation == NULL)
330
- return NULL;
331
- return nfs_detach_delegation(nfsi, delegation, server);
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(old);
396
+ }
332397 }
333398
334399 static void
....@@ -339,6 +404,14 @@
339404 delegation->stateid.seqid = update->stateid.seqid;
340405 smp_wmb();
341406 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, update->cred);
411
+ /* smp_mb__before_atomic() is implicit due to xchg() */
412
+ clear_bit(NFS_DELEGATION_REVOKED, &delegation->flags);
413
+ atomic_long_inc(&nfs_active_delegations);
414
+ }
342415 }
343416 }
344417
....@@ -352,7 +425,7 @@
352425 *
353426 * Returns zero on success, or a negative errno value.
354427 */
355
-int nfs_inode_set_delegation(struct inode *inode, struct rpc_cred *cred,
428
+int nfs_inode_set_delegation(struct inode *inode, const struct cred *cred,
356429 fmode_t type,
357430 const nfs4_stateid *stateid,
358431 unsigned long pagemod_limit)
....@@ -368,10 +441,11 @@
368441 if (delegation == NULL)
369442 return -ENOMEM;
370443 nfs4_stateid_copy(&delegation->stateid, stateid);
444
+ refcount_set(&delegation->refcount, 1);
371445 delegation->type = type;
372446 delegation->pagemod_limit = pagemod_limit;
373447 delegation->change_attr = inode_peek_iversion_raw(inode);
374
- delegation->cred = get_rpccred(cred);
448
+ delegation->cred = get_cred(cred);
375449 delegation->inode = inode;
376450 delegation->flags = 1<<NFS_DELEGATION_REFERENCED;
377451 spin_lock_init(&delegation->lock);
....@@ -379,14 +453,18 @@
379453 spin_lock(&clp->cl_lock);
380454 old_delegation = rcu_dereference_protected(nfsi->delegation,
381455 lockdep_is_held(&clp->cl_lock));
382
- if (old_delegation != NULL) {
383
- /* Is this an update of the existing delegation? */
384
- if (nfs4_stateid_match_other(&old_delegation->stateid,
385
- &delegation->stateid)) {
386
- nfs_update_inplace_delegation(old_delegation,
387
- delegation);
388
- goto out;
389
- }
456
+ if (old_delegation == NULL)
457
+ goto add_new;
458
+ /* Is this an update of the existing delegation? */
459
+ if (nfs4_stateid_match_other(&old_delegation->stateid,
460
+ &delegation->stateid)) {
461
+ spin_lock(&old_delegation->lock);
462
+ nfs_update_inplace_delegation(old_delegation,
463
+ delegation);
464
+ spin_unlock(&old_delegation->lock);
465
+ goto out;
466
+ }
467
+ if (!test_bit(NFS_DELEGATION_REVOKED, &old_delegation->flags)) {
390468 /*
391469 * Deal with broken servers that hand out two
392470 * delegations for the same file.
....@@ -405,14 +483,16 @@
405483 if (test_and_set_bit(NFS_DELEGATION_RETURNING,
406484 &old_delegation->flags))
407485 goto out;
408
- freeme = nfs_detach_delegation_locked(nfsi,
409
- old_delegation, clp);
410
- if (freeme == NULL)
411
- goto out;
412486 }
487
+ freeme = nfs_detach_delegation_locked(nfsi, old_delegation, clp);
488
+ if (freeme == NULL)
489
+ goto out;
490
+add_new:
413491 list_add_tail_rcu(&delegation->super_list, &server->delegations);
414492 rcu_assign_pointer(nfsi->delegation, delegation);
415493 delegation = NULL;
494
+
495
+ atomic_long_inc(&nfs_active_delegations);
416496
417497 trace_nfs4_set_delegation(inode, type);
418498
....@@ -423,9 +503,11 @@
423503 out:
424504 spin_unlock(&clp->cl_lock);
425505 if (delegation != NULL)
426
- nfs_free_delegation(delegation);
427
- if (freeme != NULL)
506
+ __nfs_free_delegation(delegation);
507
+ if (freeme != NULL) {
428508 nfs_do_return_delegation(inode, freeme, 0);
509
+ nfs_free_delegation(freeme);
510
+ }
429511 return status;
430512 }
431513
....@@ -435,7 +517,6 @@
435517 static int nfs_end_delegation_return(struct inode *inode, struct nfs_delegation *delegation, int issync)
436518 {
437519 struct nfs_client *clp = NFS_SERVER(inode)->nfs_client;
438
- struct nfs_inode *nfsi = NFS_I(inode);
439520 int err = 0;
440521
441522 if (delegation == NULL)
....@@ -454,14 +535,14 @@
454535 } while (err == 0);
455536
456537 if (err) {
457
- nfs_abort_delegation_return(delegation, clp);
538
+ nfs_abort_delegation_return(delegation, clp, err);
458539 goto out;
459540 }
460
- if (!nfs_detach_delegation(nfsi, delegation, NFS_SERVER(inode)))
461
- goto out;
462541
463542 err = nfs_do_return_delegation(inode, delegation, issync);
464543 out:
544
+ /* Refcount matched in nfs_start_delegation_return_locked() */
545
+ nfs_put_delegation(delegation);
465546 return err;
466547 }
467548
....@@ -469,11 +550,9 @@
469550 {
470551 bool ret = false;
471552
472
- if (test_bit(NFS_DELEGATION_RETURNING, &delegation->flags))
473
- goto out;
474553 if (test_and_clear_bit(NFS_DELEGATION_RETURN, &delegation->flags))
475554 ret = true;
476
- if (test_and_clear_bit(NFS_DELEGATION_RETURN_IF_CLOSED, &delegation->flags) && !ret) {
555
+ else if (test_bit(NFS_DELEGATION_RETURN_IF_CLOSED, &delegation->flags)) {
477556 struct inode *inode;
478557
479558 spin_lock(&delegation->lock);
....@@ -482,6 +561,117 @@
482561 ret = true;
483562 spin_unlock(&delegation->lock);
484563 }
564
+ if (ret)
565
+ clear_bit(NFS_DELEGATION_RETURN_IF_CLOSED, &delegation->flags);
566
+ if (test_bit(NFS_DELEGATION_RETURNING, &delegation->flags) ||
567
+ test_bit(NFS_DELEGATION_RETURN_DELAYED, &delegation->flags) ||
568
+ test_bit(NFS_DELEGATION_REVOKED, &delegation->flags))
569
+ ret = false;
570
+
571
+ return ret;
572
+}
573
+
574
+static int nfs_server_return_marked_delegations(struct nfs_server *server,
575
+ void __always_unused *data)
576
+{
577
+ struct nfs_delegation *delegation;
578
+ struct nfs_delegation *prev;
579
+ struct inode *inode;
580
+ struct inode *place_holder = NULL;
581
+ struct nfs_delegation *place_holder_deleg = NULL;
582
+ int err = 0;
583
+
584
+restart:
585
+ /*
586
+ * To avoid quadratic looping we hold a reference
587
+ * to an inode place_holder. Each time we restart, we
588
+ * list delegation in the server from the delegations
589
+ * of that inode.
590
+ * prev is an RCU-protected pointer to a delegation which
591
+ * wasn't marked for return and might be a good choice for
592
+ * the next place_holder.
593
+ */
594
+ prev = NULL;
595
+ delegation = NULL;
596
+ rcu_read_lock();
597
+ if (place_holder)
598
+ delegation = rcu_dereference(NFS_I(place_holder)->delegation);
599
+ if (!delegation || delegation != place_holder_deleg)
600
+ delegation = list_entry_rcu(server->delegations.next,
601
+ struct nfs_delegation, super_list);
602
+ list_for_each_entry_from_rcu(delegation, &server->delegations, super_list) {
603
+ struct inode *to_put = NULL;
604
+
605
+ if (test_bit(NFS_DELEGATION_INODE_FREEING, &delegation->flags))
606
+ continue;
607
+ if (!nfs_delegation_need_return(delegation)) {
608
+ if (nfs4_is_valid_delegation(delegation, 0))
609
+ prev = delegation;
610
+ continue;
611
+ }
612
+
613
+ if (prev) {
614
+ struct inode *tmp = nfs_delegation_grab_inode(prev);
615
+ if (tmp) {
616
+ to_put = place_holder;
617
+ place_holder = tmp;
618
+ place_holder_deleg = prev;
619
+ }
620
+ }
621
+
622
+ inode = nfs_delegation_grab_inode(delegation);
623
+ if (inode == NULL) {
624
+ rcu_read_unlock();
625
+ iput(to_put);
626
+ goto restart;
627
+ }
628
+ delegation = nfs_start_delegation_return_locked(NFS_I(inode));
629
+ rcu_read_unlock();
630
+
631
+ iput(to_put);
632
+
633
+ err = nfs_end_delegation_return(inode, delegation, 0);
634
+ iput(inode);
635
+ cond_resched();
636
+ if (!err)
637
+ goto restart;
638
+ set_bit(NFS4CLNT_DELEGRETURN, &server->nfs_client->cl_state);
639
+ goto out;
640
+ }
641
+ rcu_read_unlock();
642
+out:
643
+ iput(place_holder);
644
+ return err;
645
+}
646
+
647
+static bool nfs_server_clear_delayed_delegations(struct nfs_server *server)
648
+{
649
+ struct nfs_delegation *d;
650
+ bool ret = false;
651
+
652
+ list_for_each_entry_rcu (d, &server->delegations, super_list) {
653
+ if (!test_bit(NFS_DELEGATION_RETURN_DELAYED, &d->flags))
654
+ continue;
655
+ nfs_mark_return_delegation(server, d);
656
+ clear_bit(NFS_DELEGATION_RETURN_DELAYED, &d->flags);
657
+ ret = true;
658
+ }
659
+ return ret;
660
+}
661
+
662
+static bool nfs_client_clear_delayed_delegations(struct nfs_client *clp)
663
+{
664
+ struct nfs_server *server;
665
+ bool ret = false;
666
+
667
+ if (!test_and_clear_bit(NFS4CLNT_DELEGRETURN_DELAYED, &clp->cl_state))
668
+ goto out;
669
+ rcu_read_lock();
670
+ list_for_each_entry_rcu (server, &clp->cl_superblocks, client_link) {
671
+ if (nfs_server_clear_delayed_delegations(server))
672
+ ret = true;
673
+ }
674
+ rcu_read_unlock();
485675 out:
486676 return ret;
487677 }
....@@ -498,106 +688,35 @@
498688 */
499689 int nfs_client_return_marked_delegations(struct nfs_client *clp)
500690 {
501
- struct nfs_delegation *delegation;
502
- struct nfs_delegation *prev;
503
- struct nfs_server *server;
504
- struct inode *inode;
505
- struct inode *place_holder = NULL;
506
- struct nfs_delegation *place_holder_deleg = NULL;
507
- int err = 0;
508
-
509
-restart:
510
- /*
511
- * To avoid quadratic looping we hold a reference
512
- * to an inode place_holder. Each time we restart, we
513
- * list nfs_servers from the server of that inode, and
514
- * delegation in the server from the delegations of that
515
- * inode.
516
- * prev is an RCU-protected pointer to a delegation which
517
- * wasn't marked for return and might be a good choice for
518
- * the next place_holder.
519
- */
520
- rcu_read_lock();
521
- prev = NULL;
522
- if (place_holder)
523
- server = NFS_SERVER(place_holder);
524
- else
525
- server = list_entry_rcu(clp->cl_superblocks.next,
526
- struct nfs_server, client_link);
527
- list_for_each_entry_from_rcu(server, &clp->cl_superblocks, client_link) {
528
- delegation = NULL;
529
- if (place_holder && server == NFS_SERVER(place_holder))
530
- delegation = rcu_dereference(NFS_I(place_holder)->delegation);
531
- if (!delegation || delegation != place_holder_deleg)
532
- delegation = list_entry_rcu(server->delegations.next,
533
- struct nfs_delegation, super_list);
534
- list_for_each_entry_from_rcu(delegation, &server->delegations, super_list) {
535
- struct inode *to_put = NULL;
536
-
537
- if (!nfs_delegation_need_return(delegation)) {
538
- prev = delegation;
539
- continue;
540
- }
541
- if (!nfs_sb_active(server->super))
542
- break; /* continue in outer loop */
543
-
544
- if (prev) {
545
- struct inode *tmp;
546
-
547
- tmp = nfs_delegation_grab_inode(prev);
548
- if (tmp) {
549
- to_put = place_holder;
550
- place_holder = tmp;
551
- place_holder_deleg = prev;
552
- }
553
- }
554
-
555
- inode = nfs_delegation_grab_inode(delegation);
556
- if (inode == NULL) {
557
- rcu_read_unlock();
558
- if (to_put)
559
- iput(to_put);
560
- nfs_sb_deactive(server->super);
561
- goto restart;
562
- }
563
- delegation = nfs_start_delegation_return_locked(NFS_I(inode));
564
- rcu_read_unlock();
565
-
566
- if (to_put)
567
- iput(to_put);
568
-
569
- err = nfs_end_delegation_return(inode, delegation, 0);
570
- iput(inode);
571
- nfs_sb_deactive(server->super);
572
- cond_resched();
573
- if (!err)
574
- goto restart;
575
- set_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state);
576
- if (place_holder)
577
- iput(place_holder);
578
- return err;
579
- }
580
- }
581
- rcu_read_unlock();
582
- if (place_holder)
583
- iput(place_holder);
691
+ int err = nfs_client_for_each_server(
692
+ clp, nfs_server_return_marked_delegations, NULL);
693
+ if (err)
694
+ return err;
695
+ /* If a return was delayed, sleep to prevent hard looping */
696
+ if (nfs_client_clear_delayed_delegations(clp))
697
+ ssleep(1);
584698 return 0;
585699 }
586700
587701 /**
588
- * nfs_inode_return_delegation_noreclaim - return delegation, don't reclaim opens
702
+ * nfs_inode_evict_delegation - return delegation, don't reclaim opens
589703 * @inode: inode to process
590704 *
591705 * Does not protect against delegation reclaims, therefore really only safe
592
- * to be called from nfs4_clear_inode().
706
+ * to be called from nfs4_clear_inode(). Guaranteed to always free
707
+ * the delegation structure.
593708 */
594
-void nfs_inode_return_delegation_noreclaim(struct inode *inode)
709
+void nfs_inode_evict_delegation(struct inode *inode)
595710 {
596711 struct nfs_delegation *delegation;
597712
598713 delegation = nfs_inode_detach_delegation(inode);
599
- if (delegation != NULL)
714
+ if (delegation != NULL) {
715
+ set_bit(NFS_DELEGATION_RETURNING, &delegation->flags);
716
+ set_bit(NFS_DELEGATION_INODE_FREEING, &delegation->flags);
600717 nfs_do_return_delegation(inode, delegation, 1);
718
+ nfs_free_delegation(delegation);
719
+ }
601720 }
602721
603722 /**
....@@ -624,6 +743,43 @@
624743 }
625744
626745 /**
746
+ * nfs_inode_return_delegation_on_close - asynchronously return a delegation
747
+ * @inode: inode to process
748
+ *
749
+ * This routine is called on file close in order to determine if the
750
+ * inode delegation needs to be returned immediately.
751
+ */
752
+void nfs4_inode_return_delegation_on_close(struct inode *inode)
753
+{
754
+ struct nfs_delegation *delegation;
755
+ struct nfs_delegation *ret = NULL;
756
+
757
+ if (!inode)
758
+ return;
759
+ rcu_read_lock();
760
+ delegation = nfs4_get_valid_delegation(inode);
761
+ if (!delegation)
762
+ goto out;
763
+ if (test_bit(NFS_DELEGATION_RETURN_IF_CLOSED, &delegation->flags) ||
764
+ atomic_long_read(&nfs_active_delegations) >= nfs_delegation_watermark) {
765
+ spin_lock(&delegation->lock);
766
+ if (delegation->inode &&
767
+ list_empty(&NFS_I(inode)->open_files) &&
768
+ !test_and_set_bit(NFS_DELEGATION_RETURNING, &delegation->flags)) {
769
+ clear_bit(NFS_DELEGATION_RETURN_IF_CLOSED, &delegation->flags);
770
+ /* Refcount matched in nfs_end_delegation_return() */
771
+ ret = nfs_get_delegation(delegation);
772
+ }
773
+ spin_unlock(&delegation->lock);
774
+ if (ret)
775
+ nfs_clear_verifier_delegated(inode);
776
+ }
777
+out:
778
+ rcu_read_unlock();
779
+ nfs_end_delegation_return(inode, ret, 0);
780
+}
781
+
782
+/**
627783 * nfs4_inode_make_writeable
628784 * @inode: pointer to inode
629785 *
....@@ -633,23 +789,24 @@
633789 */
634790 int nfs4_inode_make_writeable(struct inode *inode)
635791 {
636
- if (!nfs4_has_session(NFS_SERVER(inode)->nfs_client) ||
637
- !nfs4_check_delegation(inode, FMODE_WRITE))
638
- return nfs4_inode_return_delegation(inode);
639
- return 0;
792
+ struct nfs_delegation *delegation;
793
+
794
+ rcu_read_lock();
795
+ delegation = nfs4_get_valid_delegation(inode);
796
+ if (delegation == NULL ||
797
+ (nfs4_has_session(NFS_SERVER(inode)->nfs_client) &&
798
+ (delegation->type & FMODE_WRITE))) {
799
+ rcu_read_unlock();
800
+ return 0;
801
+ }
802
+ rcu_read_unlock();
803
+ return nfs4_inode_return_delegation(inode);
640804 }
641805
642806 static void nfs_mark_return_if_closed_delegation(struct nfs_server *server,
643807 struct nfs_delegation *delegation)
644808 {
645809 set_bit(NFS_DELEGATION_RETURN_IF_CLOSED, &delegation->flags);
646
- set_bit(NFS4CLNT_DELEGRETURN, &server->nfs_client->cl_state);
647
-}
648
-
649
-static void nfs_mark_return_delegation(struct nfs_server *server,
650
- struct nfs_delegation *delegation)
651
-{
652
- set_bit(NFS_DELEGATION_RETURN, &delegation->flags);
653810 set_bit(NFS4CLNT_DELEGRETURN, &server->nfs_client->cl_state);
654811 }
655812
....@@ -694,7 +851,7 @@
694851
695852 /**
696853 * nfs_super_return_all_delegations - return delegations for one superblock
697
- * @sb: sb to process
854
+ * @server: pointer to nfs_server to process
698855 *
699856 */
700857 void nfs_server_return_all_delegations(struct nfs_server *server)
....@@ -739,15 +896,7 @@
739896 rcu_read_unlock();
740897 }
741898
742
-static void nfs_mark_delegation_revoked(struct nfs_server *server,
743
- struct nfs_delegation *delegation)
744
-{
745
- set_bit(NFS_DELEGATION_REVOKED, &delegation->flags);
746
- delegation->stateid.type = NFS4_INVALID_STATEID_TYPE;
747
- nfs_mark_return_delegation(server, delegation);
748
-}
749
-
750
-static bool nfs_revoke_delegation(struct inode *inode,
899
+static void nfs_revoke_delegation(struct inode *inode,
751900 const nfs4_stateid *stateid)
752901 {
753902 struct nfs_delegation *delegation;
....@@ -761,29 +910,69 @@
761910 if (stateid == NULL) {
762911 nfs4_stateid_copy(&tmp, &delegation->stateid);
763912 stateid = &tmp;
764
- } else if (!nfs4_stateid_match(stateid, &delegation->stateid))
765
- goto out;
766
- nfs_mark_delegation_revoked(NFS_SERVER(inode), delegation);
913
+ } else {
914
+ if (!nfs4_stateid_match_other(stateid, &delegation->stateid))
915
+ goto out;
916
+ spin_lock(&delegation->lock);
917
+ if (stateid->seqid) {
918
+ if (nfs4_stateid_is_newer(&delegation->stateid, stateid)) {
919
+ spin_unlock(&delegation->lock);
920
+ goto out;
921
+ }
922
+ delegation->stateid.seqid = stateid->seqid;
923
+ }
924
+ spin_unlock(&delegation->lock);
925
+ }
926
+ nfs_mark_delegation_revoked(delegation);
767927 ret = true;
768928 out:
769929 rcu_read_unlock();
770930 if (ret)
771931 nfs_inode_find_state_and_recover(inode, stateid);
772
- return ret;
773932 }
774933
775934 void nfs_remove_bad_delegation(struct inode *inode,
776935 const nfs4_stateid *stateid)
777936 {
778
- struct nfs_delegation *delegation;
779
-
780
- if (!nfs_revoke_delegation(inode, stateid))
781
- return;
782
- delegation = nfs_inode_detach_delegation(inode);
783
- if (delegation)
784
- nfs_free_delegation(delegation);
937
+ nfs_revoke_delegation(inode, stateid);
785938 }
786939 EXPORT_SYMBOL_GPL(nfs_remove_bad_delegation);
940
+
941
+void nfs_delegation_mark_returned(struct inode *inode,
942
+ const nfs4_stateid *stateid)
943
+{
944
+ struct nfs_delegation *delegation;
945
+
946
+ if (!inode)
947
+ return;
948
+
949
+ rcu_read_lock();
950
+ delegation = rcu_dereference(NFS_I(inode)->delegation);
951
+ if (!delegation)
952
+ goto out_rcu_unlock;
953
+
954
+ spin_lock(&delegation->lock);
955
+ if (!nfs4_stateid_match_other(stateid, &delegation->stateid))
956
+ goto out_spin_unlock;
957
+ if (stateid->seqid) {
958
+ /* If delegation->stateid is newer, dont mark as returned */
959
+ if (nfs4_stateid_is_newer(&delegation->stateid, stateid))
960
+ goto out_clear_returning;
961
+ if (delegation->stateid.seqid != stateid->seqid)
962
+ delegation->stateid.seqid = stateid->seqid;
963
+ }
964
+
965
+ nfs_mark_delegation_revoked(delegation);
966
+
967
+out_clear_returning:
968
+ clear_bit(NFS_DELEGATION_RETURNING, &delegation->flags);
969
+out_spin_unlock:
970
+ spin_unlock(&delegation->lock);
971
+out_rcu_unlock:
972
+ rcu_read_unlock();
973
+
974
+ nfs_inode_find_state_and_recover(inode, stateid);
975
+}
787976
788977 /**
789978 * nfs_expire_unused_delegation_types
....@@ -840,7 +1029,7 @@
8401029 struct nfs_delegation *delegation;
8411030
8421031 rcu_read_lock();
843
- delegation = rcu_dereference(NFS_I(inode)->delegation);
1032
+ delegation = nfs4_get_valid_delegation(inode);
8441033 if (delegation == NULL)
8451034 goto out_enoent;
8461035 if (stateid != NULL &&
....@@ -861,21 +1050,24 @@
8611050 const struct nfs_fh *fhandle)
8621051 {
8631052 struct nfs_delegation *delegation;
864
- struct inode *freeme, *res = NULL;
1053
+ struct super_block *freeme = NULL;
1054
+ struct inode *res = NULL;
8651055
8661056 list_for_each_entry_rcu(delegation, &server->delegations, super_list) {
8671057 spin_lock(&delegation->lock);
8681058 if (delegation->inode != NULL &&
1059
+ !test_bit(NFS_DELEGATION_REVOKED, &delegation->flags) &&
8691060 nfs_compare_fh(fhandle, &NFS_I(delegation->inode)->fh) == 0) {
870
- freeme = igrab(delegation->inode);
871
- if (freeme && nfs_sb_active(freeme->i_sb))
872
- res = freeme;
1061
+ if (nfs_sb_active(server->super)) {
1062
+ freeme = server->super;
1063
+ res = igrab(delegation->inode);
1064
+ }
8731065 spin_unlock(&delegation->lock);
8741066 if (res != NULL)
8751067 return res;
8761068 if (freeme) {
8771069 rcu_read_unlock();
878
- iput(freeme);
1070
+ nfs_sb_deactive(freeme);
8791071 rcu_read_lock();
8801072 }
8811073 return ERR_PTR(-EAGAIN);
....@@ -941,6 +1133,42 @@
9411133 rcu_read_unlock();
9421134 }
9431135
1136
+static int nfs_server_reap_unclaimed_delegations(struct nfs_server *server,
1137
+ void __always_unused *data)
1138
+{
1139
+ struct nfs_delegation *delegation;
1140
+ struct inode *inode;
1141
+restart:
1142
+ rcu_read_lock();
1143
+restart_locked:
1144
+ list_for_each_entry_rcu(delegation, &server->delegations, super_list) {
1145
+ if (test_bit(NFS_DELEGATION_INODE_FREEING,
1146
+ &delegation->flags) ||
1147
+ test_bit(NFS_DELEGATION_RETURNING,
1148
+ &delegation->flags) ||
1149
+ test_bit(NFS_DELEGATION_NEED_RECLAIM,
1150
+ &delegation->flags) == 0)
1151
+ continue;
1152
+ inode = nfs_delegation_grab_inode(delegation);
1153
+ if (inode == NULL)
1154
+ goto restart_locked;
1155
+ delegation = nfs_start_delegation_return_locked(NFS_I(inode));
1156
+ rcu_read_unlock();
1157
+ if (delegation != NULL) {
1158
+ if (nfs_detach_delegation(NFS_I(inode), delegation,
1159
+ server) != NULL)
1160
+ nfs_free_delegation(delegation);
1161
+ /* Match nfs_start_delegation_return_locked */
1162
+ nfs_put_delegation(delegation);
1163
+ }
1164
+ iput(inode);
1165
+ cond_resched();
1166
+ goto restart;
1167
+ }
1168
+ rcu_read_unlock();
1169
+ return 0;
1170
+}
1171
+
9441172 /**
9451173 * nfs_delegation_reap_unclaimed - reap unclaimed delegations after reboot recovery is done
9461174 * @clp: nfs_client to process
....@@ -948,45 +1176,8 @@
9481176 */
9491177 void nfs_delegation_reap_unclaimed(struct nfs_client *clp)
9501178 {
951
- struct nfs_delegation *delegation;
952
- struct nfs_server *server;
953
- struct inode *inode;
954
-
955
-restart:
956
- rcu_read_lock();
957
- list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
958
- list_for_each_entry_rcu(delegation, &server->delegations,
959
- super_list) {
960
- if (test_bit(NFS_DELEGATION_INODE_FREEING,
961
- &delegation->flags) ||
962
- test_bit(NFS_DELEGATION_RETURNING,
963
- &delegation->flags) ||
964
- test_bit(NFS_DELEGATION_NEED_RECLAIM,
965
- &delegation->flags) == 0)
966
- continue;
967
- if (!nfs_sb_active(server->super))
968
- break; /* continue in outer loop */
969
- inode = nfs_delegation_grab_inode(delegation);
970
- if (inode == NULL) {
971
- rcu_read_unlock();
972
- nfs_sb_deactive(server->super);
973
- goto restart;
974
- }
975
- delegation = nfs_start_delegation_return_locked(NFS_I(inode));
976
- rcu_read_unlock();
977
- if (delegation != NULL) {
978
- delegation = nfs_detach_delegation(NFS_I(inode),
979
- delegation, server);
980
- if (delegation != NULL)
981
- nfs_free_delegation(delegation);
982
- }
983
- iput(inode);
984
- nfs_sb_deactive(server->super);
985
- cond_resched();
986
- goto restart;
987
- }
988
- }
989
- rcu_read_unlock();
1179
+ nfs_client_for_each_server(clp, nfs_server_reap_unclaimed_delegations,
1180
+ NULL);
9901181 }
9911182
9921183 static inline bool nfs4_server_rebooted(const struct nfs_client *clp)
....@@ -1045,6 +1236,76 @@
10451236 }
10461237
10471238 /**
1239
+ * nfs_test_expired_all_delegations - test all delegations for a client
1240
+ * @clp: nfs_client to process
1241
+ *
1242
+ * Helper for handling "recallable state revoked" status from server.
1243
+ */
1244
+void nfs_test_expired_all_delegations(struct nfs_client *clp)
1245
+{
1246
+ nfs_mark_test_expired_all_delegations(clp);
1247
+ nfs4_schedule_state_manager(clp);
1248
+}
1249
+
1250
+static void
1251
+nfs_delegation_test_free_expired(struct inode *inode,
1252
+ nfs4_stateid *stateid,
1253
+ const struct cred *cred)
1254
+{
1255
+ struct nfs_server *server = NFS_SERVER(inode);
1256
+ const struct nfs4_minor_version_ops *ops = server->nfs_client->cl_mvops;
1257
+ int status;
1258
+
1259
+ if (!cred)
1260
+ return;
1261
+ status = ops->test_and_free_expired(server, stateid, cred);
1262
+ if (status == -NFS4ERR_EXPIRED || status == -NFS4ERR_BAD_STATEID)
1263
+ nfs_remove_bad_delegation(inode, stateid);
1264
+}
1265
+
1266
+static int nfs_server_reap_expired_delegations(struct nfs_server *server,
1267
+ void __always_unused *data)
1268
+{
1269
+ struct nfs_delegation *delegation;
1270
+ struct inode *inode;
1271
+ const struct cred *cred;
1272
+ nfs4_stateid stateid;
1273
+restart:
1274
+ rcu_read_lock();
1275
+restart_locked:
1276
+ list_for_each_entry_rcu(delegation, &server->delegations, super_list) {
1277
+ if (test_bit(NFS_DELEGATION_INODE_FREEING,
1278
+ &delegation->flags) ||
1279
+ test_bit(NFS_DELEGATION_RETURNING,
1280
+ &delegation->flags) ||
1281
+ test_bit(NFS_DELEGATION_TEST_EXPIRED,
1282
+ &delegation->flags) == 0)
1283
+ continue;
1284
+ inode = nfs_delegation_grab_inode(delegation);
1285
+ if (inode == NULL)
1286
+ goto restart_locked;
1287
+ spin_lock(&delegation->lock);
1288
+ cred = get_cred_rcu(delegation->cred);
1289
+ nfs4_stateid_copy(&stateid, &delegation->stateid);
1290
+ spin_unlock(&delegation->lock);
1291
+ clear_bit(NFS_DELEGATION_TEST_EXPIRED, &delegation->flags);
1292
+ rcu_read_unlock();
1293
+ nfs_delegation_test_free_expired(inode, &stateid, cred);
1294
+ put_cred(cred);
1295
+ if (!nfs4_server_rebooted(server->nfs_client)) {
1296
+ iput(inode);
1297
+ cond_resched();
1298
+ goto restart;
1299
+ }
1300
+ nfs_inode_mark_test_expired_delegation(server,inode);
1301
+ iput(inode);
1302
+ return -EAGAIN;
1303
+ }
1304
+ rcu_read_unlock();
1305
+ return 0;
1306
+}
1307
+
1308
+/**
10481309 * nfs_reap_expired_delegations - reap expired delegations
10491310 * @clp: nfs_client to process
10501311 *
....@@ -1055,56 +1316,8 @@
10551316 */
10561317 void nfs_reap_expired_delegations(struct nfs_client *clp)
10571318 {
1058
- const struct nfs4_minor_version_ops *ops = clp->cl_mvops;
1059
- struct nfs_delegation *delegation;
1060
- struct nfs_server *server;
1061
- struct inode *inode;
1062
- struct rpc_cred *cred;
1063
- nfs4_stateid stateid;
1064
-
1065
-restart:
1066
- rcu_read_lock();
1067
- list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
1068
- list_for_each_entry_rcu(delegation, &server->delegations,
1069
- super_list) {
1070
- if (test_bit(NFS_DELEGATION_INODE_FREEING,
1071
- &delegation->flags) ||
1072
- test_bit(NFS_DELEGATION_RETURNING,
1073
- &delegation->flags) ||
1074
- test_bit(NFS_DELEGATION_TEST_EXPIRED,
1075
- &delegation->flags) == 0)
1076
- continue;
1077
- if (!nfs_sb_active(server->super))
1078
- break; /* continue in outer loop */
1079
- inode = nfs_delegation_grab_inode(delegation);
1080
- if (inode == NULL) {
1081
- rcu_read_unlock();
1082
- nfs_sb_deactive(server->super);
1083
- goto restart;
1084
- }
1085
- cred = get_rpccred_rcu(delegation->cred);
1086
- nfs4_stateid_copy(&stateid, &delegation->stateid);
1087
- clear_bit(NFS_DELEGATION_TEST_EXPIRED, &delegation->flags);
1088
- rcu_read_unlock();
1089
- if (cred != NULL &&
1090
- ops->test_and_free_expired(server, &stateid, cred) < 0) {
1091
- nfs_revoke_delegation(inode, &stateid);
1092
- nfs_inode_find_state_and_recover(inode, &stateid);
1093
- }
1094
- put_rpccred(cred);
1095
- if (nfs4_server_rebooted(clp)) {
1096
- nfs_inode_mark_test_expired_delegation(server,inode);
1097
- iput(inode);
1098
- nfs_sb_deactive(server->super);
1099
- return;
1100
- }
1101
- iput(inode);
1102
- nfs_sb_deactive(server->super);
1103
- cond_resched();
1104
- goto restart;
1105
- }
1106
- }
1107
- rcu_read_unlock();
1319
+ nfs_client_for_each_server(clp, nfs_server_reap_expired_delegations,
1320
+ NULL);
11081321 }
11091322
11101323 void nfs_inode_find_delegation_state_and_recover(struct inode *inode,
....@@ -1117,7 +1330,8 @@
11171330 rcu_read_lock();
11181331 delegation = rcu_dereference(NFS_I(inode)->delegation);
11191332 if (delegation &&
1120
- nfs4_stateid_match_other(&delegation->stateid, stateid)) {
1333
+ nfs4_stateid_match_or_older(&delegation->stateid, stateid) &&
1334
+ !test_bit(NFS_DELEGATION_REVOKED, &delegation->flags)) {
11211335 nfs_mark_test_expired_delegation(NFS_SERVER(inode), delegation);
11221336 found = true;
11231337 }
....@@ -1166,7 +1380,9 @@
11661380 rcu_read_lock();
11671381 delegation = rcu_dereference(NFS_I(inode)->delegation);
11681382 if (delegation != NULL &&
1169
- nfs4_stateid_match_other(dst, &delegation->stateid)) {
1383
+ nfs4_stateid_match_other(dst, &delegation->stateid) &&
1384
+ nfs4_stateid_is_newer(&delegation->stateid, dst) &&
1385
+ !test_bit(NFS_DELEGATION_REVOKED, &delegation->flags)) {
11701386 dst->seqid = delegation->stateid.seqid;
11711387 ret = true;
11721388 }
....@@ -1186,22 +1402,27 @@
11861402 * otherwise "false" is returned.
11871403 */
11881404 bool nfs4_copy_delegation_stateid(struct inode *inode, fmode_t flags,
1189
- nfs4_stateid *dst, struct rpc_cred **cred)
1405
+ nfs4_stateid *dst, const struct cred **cred)
11901406 {
11911407 struct nfs_inode *nfsi = NFS_I(inode);
11921408 struct nfs_delegation *delegation;
1193
- bool ret;
1409
+ bool ret = false;
11941410
11951411 flags &= FMODE_READ|FMODE_WRITE;
11961412 rcu_read_lock();
11971413 delegation = rcu_dereference(nfsi->delegation);
1414
+ if (!delegation)
1415
+ goto out;
1416
+ spin_lock(&delegation->lock);
11981417 ret = nfs4_is_valid_delegation(delegation, flags);
11991418 if (ret) {
12001419 nfs4_stateid_copy(dst, &delegation->stateid);
12011420 nfs_mark_delegation_referenced(delegation);
12021421 if (cred)
1203
- *cred = get_rpccred(delegation->cred);
1422
+ *cred = get_cred(delegation->cred);
12041423 }
1424
+ spin_unlock(&delegation->lock);
1425
+out:
12051426 rcu_read_unlock();
12061427 return ret;
12071428 }
....@@ -1230,3 +1451,5 @@
12301451 rcu_read_unlock();
12311452 return ret;
12321453 }
1454
+
1455
+module_param_named(delegation_watermark, nfs_delegation_watermark, uint, 0644);