1 // SPDX-License-Identifier: GPL-2.0-only
3 * linux/fs/nfs/delegation.c
5 * Copyright (C) 2004 Trond Myklebust
7 * NFS file delegation management
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>
18 #include <linux/nfs4.h>
19 #include <linux/nfs_fs.h>
20 #include <linux/nfs_xdr.h>
23 #include "nfs4session.h"
24 #include "delegation.h"
26 #include "nfs4trace.h"
28 static void nfs_free_delegation(struct nfs_delegation *delegation)
30 put_cred(delegation->cred);
31 delegation->cred = NULL;
32 kfree_rcu(delegation, rcu);
36 * nfs_mark_delegation_referenced - set delegation's REFERENCED flag
37 * @delegation: delegation to process
40 void nfs_mark_delegation_referenced(struct nfs_delegation *delegation)
42 set_bit(NFS_DELEGATION_REFERENCED, &delegation->flags);
46 nfs4_is_valid_delegation(const struct nfs_delegation *delegation,
49 if (delegation != NULL && (delegation->type & flags) == flags &&
50 !test_bit(NFS_DELEGATION_REVOKED, &delegation->flags) &&
51 !test_bit(NFS_DELEGATION_RETURNING, &delegation->flags))
57 nfs4_do_check_delegation(struct inode *inode, fmode_t flags, bool mark)
59 struct nfs_delegation *delegation;
62 flags &= FMODE_READ|FMODE_WRITE;
64 delegation = rcu_dereference(NFS_I(inode)->delegation);
65 if (nfs4_is_valid_delegation(delegation, flags)) {
67 nfs_mark_delegation_referenced(delegation);
74 * nfs_have_delegation - check if inode has a delegation, mark it
75 * NFS_DELEGATION_REFERENCED if there is one.
76 * @inode: inode to check
77 * @flags: delegation types to check for
79 * Returns one if inode has the indicated delegation, otherwise zero.
81 int nfs4_have_delegation(struct inode *inode, fmode_t flags)
83 return nfs4_do_check_delegation(inode, flags, true);
87 * nfs4_check_delegation - check if inode has a delegation, do not mark
88 * NFS_DELEGATION_REFERENCED if it has one.
90 int nfs4_check_delegation(struct inode *inode, fmode_t flags)
92 return nfs4_do_check_delegation(inode, flags, false);
95 static int nfs_delegation_claim_locks(struct nfs4_state *state, const nfs4_stateid *stateid)
97 struct inode *inode = state->inode;
99 struct file_lock_context *flctx = inode->i_flctx;
100 struct list_head *list;
106 list = &flctx->flc_posix;
107 spin_lock(&flctx->flc_lock);
109 list_for_each_entry(fl, list, fl_list) {
110 if (nfs_file_open_context(fl->fl_file)->state != state)
112 spin_unlock(&flctx->flc_lock);
113 status = nfs4_lock_delegation_recall(fl, state, stateid);
116 spin_lock(&flctx->flc_lock);
118 if (list == &flctx->flc_posix) {
119 list = &flctx->flc_flock;
122 spin_unlock(&flctx->flc_lock);
127 static int nfs_delegation_claim_opens(struct inode *inode,
128 const nfs4_stateid *stateid, fmode_t type)
130 struct nfs_inode *nfsi = NFS_I(inode);
131 struct nfs_open_context *ctx;
132 struct nfs4_state_owner *sp;
133 struct nfs4_state *state;
139 list_for_each_entry_rcu(ctx, &nfsi->open_files, list) {
143 if (!test_bit(NFS_DELEGATED_STATE, &state->flags))
145 if (!nfs4_valid_open_stateid(state))
147 if (!nfs4_stateid_match(&state->stateid, stateid))
149 if (!get_nfs_open_context(ctx))
153 /* Block nfs4_proc_unlck */
154 mutex_lock(&sp->so_delegreturn_mutex);
155 seq = raw_seqcount_begin(&sp->so_reclaim_seqcount);
156 err = nfs4_open_delegation_recall(ctx, state, stateid);
158 err = nfs_delegation_claim_locks(state, stateid);
159 if (!err && read_seqcount_retry(&sp->so_reclaim_seqcount, seq))
161 mutex_unlock(&sp->so_delegreturn_mutex);
162 put_nfs_open_context(ctx);
172 * nfs_inode_reclaim_delegation - process a delegation reclaim request
173 * @inode: inode to process
174 * @cred: credential to use for request
175 * @type: delegation type
176 * @stateid: delegation stateid
177 * @pagemod_limit: write delegation "space_limit"
180 void nfs_inode_reclaim_delegation(struct inode *inode, const struct cred *cred,
182 const nfs4_stateid *stateid,
183 unsigned long pagemod_limit)
185 struct nfs_delegation *delegation;
186 const struct cred *oldcred = NULL;
189 delegation = rcu_dereference(NFS_I(inode)->delegation);
190 if (delegation != NULL) {
191 spin_lock(&delegation->lock);
192 if (delegation->inode != NULL) {
193 nfs4_stateid_copy(&delegation->stateid, stateid);
194 delegation->type = type;
195 delegation->pagemod_limit = pagemod_limit;
196 oldcred = delegation->cred;
197 delegation->cred = get_cred(cred);
198 clear_bit(NFS_DELEGATION_NEED_RECLAIM,
200 spin_unlock(&delegation->lock);
203 trace_nfs4_reclaim_delegation(inode, type);
206 /* We appear to have raced with a delegation return. */
207 spin_unlock(&delegation->lock);
210 nfs_inode_set_delegation(inode, cred, type, stateid, pagemod_limit);
213 static int nfs_do_return_delegation(struct inode *inode, struct nfs_delegation *delegation, int issync)
217 if (!test_bit(NFS_DELEGATION_REVOKED, &delegation->flags))
218 res = nfs4_proc_delegreturn(inode,
220 &delegation->stateid,
222 nfs_free_delegation(delegation);
226 static struct inode *nfs_delegation_grab_inode(struct nfs_delegation *delegation)
228 struct inode *inode = NULL;
230 spin_lock(&delegation->lock);
231 if (delegation->inode != NULL)
232 inode = igrab(delegation->inode);
234 set_bit(NFS_DELEGATION_INODE_FREEING, &delegation->flags);
235 spin_unlock(&delegation->lock);
239 static struct nfs_delegation *
240 nfs_start_delegation_return_locked(struct nfs_inode *nfsi)
242 struct nfs_delegation *ret = NULL;
243 struct nfs_delegation *delegation = rcu_dereference(nfsi->delegation);
245 if (delegation == NULL)
247 spin_lock(&delegation->lock);
248 if (!test_and_set_bit(NFS_DELEGATION_RETURNING, &delegation->flags))
250 spin_unlock(&delegation->lock);
255 static struct nfs_delegation *
256 nfs_start_delegation_return(struct nfs_inode *nfsi)
258 struct nfs_delegation *delegation;
261 delegation = nfs_start_delegation_return_locked(nfsi);
267 nfs_abort_delegation_return(struct nfs_delegation *delegation,
268 struct nfs_client *clp)
271 spin_lock(&delegation->lock);
272 clear_bit(NFS_DELEGATION_RETURNING, &delegation->flags);
273 set_bit(NFS_DELEGATION_RETURN, &delegation->flags);
274 spin_unlock(&delegation->lock);
275 set_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state);
278 static struct nfs_delegation *
279 nfs_detach_delegation_locked(struct nfs_inode *nfsi,
280 struct nfs_delegation *delegation,
281 struct nfs_client *clp)
283 struct nfs_delegation *deleg_cur =
284 rcu_dereference_protected(nfsi->delegation,
285 lockdep_is_held(&clp->cl_lock));
287 if (deleg_cur == NULL || delegation != deleg_cur)
290 spin_lock(&delegation->lock);
291 set_bit(NFS_DELEGATION_RETURNING, &delegation->flags);
292 list_del_rcu(&delegation->super_list);
293 delegation->inode = NULL;
294 rcu_assign_pointer(nfsi->delegation, NULL);
295 spin_unlock(&delegation->lock);
299 static struct nfs_delegation *nfs_detach_delegation(struct nfs_inode *nfsi,
300 struct nfs_delegation *delegation,
301 struct nfs_server *server)
303 struct nfs_client *clp = server->nfs_client;
305 spin_lock(&clp->cl_lock);
306 delegation = nfs_detach_delegation_locked(nfsi, delegation, clp);
307 spin_unlock(&clp->cl_lock);
311 static struct nfs_delegation *
312 nfs_inode_detach_delegation(struct inode *inode)
314 struct nfs_inode *nfsi = NFS_I(inode);
315 struct nfs_server *server = NFS_SERVER(inode);
316 struct nfs_delegation *delegation;
318 delegation = nfs_start_delegation_return(nfsi);
319 if (delegation == NULL)
321 return nfs_detach_delegation(nfsi, delegation, server);
325 nfs_update_inplace_delegation(struct nfs_delegation *delegation,
326 const struct nfs_delegation *update)
328 if (nfs4_stateid_is_newer(&update->stateid, &delegation->stateid)) {
329 delegation->stateid.seqid = update->stateid.seqid;
331 delegation->type = update->type;
336 * nfs_inode_set_delegation - set up a delegation on an inode
337 * @inode: inode to which delegation applies
338 * @cred: cred to use for subsequent delegation processing
339 * @type: delegation type
340 * @stateid: delegation stateid
341 * @pagemod_limit: write delegation "space_limit"
343 * Returns zero on success, or a negative errno value.
345 int nfs_inode_set_delegation(struct inode *inode, const struct cred *cred,
347 const nfs4_stateid *stateid,
348 unsigned long pagemod_limit)
350 struct nfs_server *server = NFS_SERVER(inode);
351 struct nfs_client *clp = server->nfs_client;
352 struct nfs_inode *nfsi = NFS_I(inode);
353 struct nfs_delegation *delegation, *old_delegation;
354 struct nfs_delegation *freeme = NULL;
357 delegation = kmalloc(sizeof(*delegation), GFP_NOFS);
358 if (delegation == NULL)
360 nfs4_stateid_copy(&delegation->stateid, stateid);
361 delegation->type = type;
362 delegation->pagemod_limit = pagemod_limit;
363 delegation->change_attr = inode_peek_iversion_raw(inode);
364 delegation->cred = get_cred(cred);
365 delegation->inode = inode;
366 delegation->flags = 1<<NFS_DELEGATION_REFERENCED;
367 spin_lock_init(&delegation->lock);
369 spin_lock(&clp->cl_lock);
370 old_delegation = rcu_dereference_protected(nfsi->delegation,
371 lockdep_is_held(&clp->cl_lock));
372 if (old_delegation != NULL) {
373 /* Is this an update of the existing delegation? */
374 if (nfs4_stateid_match_other(&old_delegation->stateid,
375 &delegation->stateid)) {
376 nfs_update_inplace_delegation(old_delegation,
381 * Deal with broken servers that hand out two
382 * delegations for the same file.
383 * Allow for upgrades to a WRITE delegation, but
386 dfprintk(FILE, "%s: server %s handed out "
387 "a duplicate delegation!\n",
388 __func__, clp->cl_hostname);
389 if (delegation->type == old_delegation->type ||
390 !(delegation->type & FMODE_WRITE)) {
395 if (test_and_set_bit(NFS_DELEGATION_RETURNING,
396 &old_delegation->flags))
398 freeme = nfs_detach_delegation_locked(nfsi,
399 old_delegation, clp);
403 list_add_tail_rcu(&delegation->super_list, &server->delegations);
404 rcu_assign_pointer(nfsi->delegation, delegation);
407 trace_nfs4_set_delegation(inode, type);
409 spin_lock(&inode->i_lock);
410 if (NFS_I(inode)->cache_validity & (NFS_INO_INVALID_ATTR|NFS_INO_INVALID_ATIME))
411 NFS_I(inode)->cache_validity |= NFS_INO_REVAL_FORCED;
412 spin_unlock(&inode->i_lock);
414 spin_unlock(&clp->cl_lock);
415 if (delegation != NULL)
416 nfs_free_delegation(delegation);
418 nfs_do_return_delegation(inode, freeme, 0);
423 * Basic procedure for returning a delegation to the server
425 static int nfs_end_delegation_return(struct inode *inode, struct nfs_delegation *delegation, int issync)
427 struct nfs_client *clp = NFS_SERVER(inode)->nfs_client;
428 struct nfs_inode *nfsi = NFS_I(inode);
431 if (delegation == NULL)
434 if (test_bit(NFS_DELEGATION_REVOKED, &delegation->flags))
436 err = nfs_delegation_claim_opens(inode, &delegation->stateid,
438 if (!issync || err != -EAGAIN)
441 * Guard against state recovery
443 err = nfs4_wait_clnt_recover(clp);
447 nfs_abort_delegation_return(delegation, clp);
450 if (!nfs_detach_delegation(nfsi, delegation, NFS_SERVER(inode)))
453 err = nfs_do_return_delegation(inode, delegation, issync);
458 static bool nfs_delegation_need_return(struct nfs_delegation *delegation)
462 if (test_bit(NFS_DELEGATION_RETURNING, &delegation->flags))
464 if (test_and_clear_bit(NFS_DELEGATION_RETURN, &delegation->flags))
466 if (test_and_clear_bit(NFS_DELEGATION_RETURN_IF_CLOSED, &delegation->flags) && !ret) {
469 spin_lock(&delegation->lock);
470 inode = delegation->inode;
471 if (inode && list_empty(&NFS_I(inode)->open_files))
473 spin_unlock(&delegation->lock);
480 * nfs_client_return_marked_delegations - return previously marked delegations
481 * @clp: nfs_client to process
483 * Note that this function is designed to be called by the state
484 * manager thread. For this reason, it cannot flush the dirty data,
485 * since that could deadlock in case of a state recovery error.
487 * Returns zero on success, or a negative errno value.
489 int nfs_client_return_marked_delegations(struct nfs_client *clp)
491 struct nfs_delegation *delegation;
492 struct nfs_delegation *prev;
493 struct nfs_server *server;
495 struct inode *place_holder = NULL;
496 struct nfs_delegation *place_holder_deleg = NULL;
501 * To avoid quadratic looping we hold a reference
502 * to an inode place_holder. Each time we restart, we
503 * list nfs_servers from the server of that inode, and
504 * delegation in the server from the delegations of that
506 * prev is an RCU-protected pointer to a delegation which
507 * wasn't marked for return and might be a good choice for
508 * the next place_holder.
513 server = NFS_SERVER(place_holder);
515 server = list_entry_rcu(clp->cl_superblocks.next,
516 struct nfs_server, client_link);
517 list_for_each_entry_from_rcu(server, &clp->cl_superblocks, client_link) {
519 if (place_holder && server == NFS_SERVER(place_holder))
520 delegation = rcu_dereference(NFS_I(place_holder)->delegation);
521 if (!delegation || delegation != place_holder_deleg)
522 delegation = list_entry_rcu(server->delegations.next,
523 struct nfs_delegation, super_list);
524 list_for_each_entry_from_rcu(delegation, &server->delegations, super_list) {
525 struct inode *to_put = NULL;
527 if (!nfs_delegation_need_return(delegation)) {
531 if (!nfs_sb_active(server->super))
532 break; /* continue in outer loop */
537 tmp = nfs_delegation_grab_inode(prev);
539 to_put = place_holder;
541 place_holder_deleg = prev;
545 inode = nfs_delegation_grab_inode(delegation);
550 nfs_sb_deactive(server->super);
553 delegation = nfs_start_delegation_return_locked(NFS_I(inode));
559 err = nfs_end_delegation_return(inode, delegation, 0);
561 nfs_sb_deactive(server->super);
565 set_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state);
578 * nfs_inode_return_delegation_noreclaim - return delegation, don't reclaim opens
579 * @inode: inode to process
581 * Does not protect against delegation reclaims, therefore really only safe
582 * to be called from nfs4_clear_inode().
584 void nfs_inode_return_delegation_noreclaim(struct inode *inode)
586 struct nfs_delegation *delegation;
588 delegation = nfs_inode_detach_delegation(inode);
589 if (delegation != NULL)
590 nfs_do_return_delegation(inode, delegation, 1);
594 * nfs_inode_return_delegation - synchronously return a delegation
595 * @inode: inode to process
597 * This routine will always flush any dirty data to disk on the
598 * assumption that if we need to return the delegation, then
599 * we should stop caching.
601 * Returns zero on success, or a negative errno value.
603 int nfs4_inode_return_delegation(struct inode *inode)
605 struct nfs_inode *nfsi = NFS_I(inode);
606 struct nfs_delegation *delegation;
610 delegation = nfs_start_delegation_return(nfsi);
611 if (delegation != NULL)
612 err = nfs_end_delegation_return(inode, delegation, 1);
617 * nfs4_inode_make_writeable
618 * @inode: pointer to inode
620 * Make the inode writeable by returning the delegation if necessary
622 * Returns zero on success, or a negative errno value.
624 int nfs4_inode_make_writeable(struct inode *inode)
626 if (!nfs4_has_session(NFS_SERVER(inode)->nfs_client) ||
627 !nfs4_check_delegation(inode, FMODE_WRITE))
628 return nfs4_inode_return_delegation(inode);
632 static void nfs_mark_return_if_closed_delegation(struct nfs_server *server,
633 struct nfs_delegation *delegation)
635 set_bit(NFS_DELEGATION_RETURN_IF_CLOSED, &delegation->flags);
636 set_bit(NFS4CLNT_DELEGRETURN, &server->nfs_client->cl_state);
639 static void nfs_mark_return_delegation(struct nfs_server *server,
640 struct nfs_delegation *delegation)
642 set_bit(NFS_DELEGATION_RETURN, &delegation->flags);
643 set_bit(NFS4CLNT_DELEGRETURN, &server->nfs_client->cl_state);
646 static bool nfs_server_mark_return_all_delegations(struct nfs_server *server)
648 struct nfs_delegation *delegation;
651 list_for_each_entry_rcu(delegation, &server->delegations, super_list) {
652 nfs_mark_return_delegation(server, delegation);
658 static void nfs_client_mark_return_all_delegations(struct nfs_client *clp)
660 struct nfs_server *server;
663 list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
664 nfs_server_mark_return_all_delegations(server);
668 static void nfs_delegation_run_state_manager(struct nfs_client *clp)
670 if (test_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state))
671 nfs4_schedule_state_manager(clp);
675 * nfs_expire_all_delegations
676 * @clp: client to process
679 void nfs_expire_all_delegations(struct nfs_client *clp)
681 nfs_client_mark_return_all_delegations(clp);
682 nfs_delegation_run_state_manager(clp);
686 * nfs_super_return_all_delegations - return delegations for one superblock
687 * @server: pointer to nfs_server to process
690 void nfs_server_return_all_delegations(struct nfs_server *server)
692 struct nfs_client *clp = server->nfs_client;
699 need_wait = nfs_server_mark_return_all_delegations(server);
703 nfs4_schedule_state_manager(clp);
704 nfs4_wait_clnt_recover(clp);
708 static void nfs_mark_return_unused_delegation_types(struct nfs_server *server,
711 struct nfs_delegation *delegation;
713 list_for_each_entry_rcu(delegation, &server->delegations, super_list) {
714 if ((delegation->type == (FMODE_READ|FMODE_WRITE)) && !(flags & FMODE_WRITE))
716 if (delegation->type & flags)
717 nfs_mark_return_if_closed_delegation(server, delegation);
721 static void nfs_client_mark_return_unused_delegation_types(struct nfs_client *clp,
724 struct nfs_server *server;
727 list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
728 nfs_mark_return_unused_delegation_types(server, flags);
732 static void nfs_mark_delegation_revoked(struct nfs_server *server,
733 struct nfs_delegation *delegation)
735 set_bit(NFS_DELEGATION_REVOKED, &delegation->flags);
736 delegation->stateid.type = NFS4_INVALID_STATEID_TYPE;
737 nfs_mark_return_delegation(server, delegation);
740 static bool nfs_revoke_delegation(struct inode *inode,
741 const nfs4_stateid *stateid)
743 struct nfs_delegation *delegation;
748 delegation = rcu_dereference(NFS_I(inode)->delegation);
749 if (delegation == NULL)
751 if (stateid == NULL) {
752 nfs4_stateid_copy(&tmp, &delegation->stateid);
754 } else if (!nfs4_stateid_match(stateid, &delegation->stateid))
756 nfs_mark_delegation_revoked(NFS_SERVER(inode), delegation);
761 nfs_inode_find_state_and_recover(inode, stateid);
765 void nfs_remove_bad_delegation(struct inode *inode,
766 const nfs4_stateid *stateid)
768 struct nfs_delegation *delegation;
770 if (!nfs_revoke_delegation(inode, stateid))
772 delegation = nfs_inode_detach_delegation(inode);
774 nfs_free_delegation(delegation);
776 EXPORT_SYMBOL_GPL(nfs_remove_bad_delegation);
779 * nfs_expire_unused_delegation_types
780 * @clp: client to process
781 * @flags: delegation types to expire
784 void nfs_expire_unused_delegation_types(struct nfs_client *clp, fmode_t flags)
786 nfs_client_mark_return_unused_delegation_types(clp, flags);
787 nfs_delegation_run_state_manager(clp);
790 static void nfs_mark_return_unreferenced_delegations(struct nfs_server *server)
792 struct nfs_delegation *delegation;
794 list_for_each_entry_rcu(delegation, &server->delegations, super_list) {
795 if (test_and_clear_bit(NFS_DELEGATION_REFERENCED, &delegation->flags))
797 nfs_mark_return_if_closed_delegation(server, delegation);
802 * nfs_expire_unreferenced_delegations - Eliminate unused delegations
803 * @clp: nfs_client to process
806 void nfs_expire_unreferenced_delegations(struct nfs_client *clp)
808 struct nfs_server *server;
811 list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
812 nfs_mark_return_unreferenced_delegations(server);
815 nfs_delegation_run_state_manager(clp);
819 * nfs_async_inode_return_delegation - asynchronously return a delegation
820 * @inode: inode to process
821 * @stateid: state ID information
823 * Returns zero on success, or a negative errno value.
825 int nfs_async_inode_return_delegation(struct inode *inode,
826 const nfs4_stateid *stateid)
828 struct nfs_server *server = NFS_SERVER(inode);
829 struct nfs_client *clp = server->nfs_client;
830 struct nfs_delegation *delegation;
833 delegation = rcu_dereference(NFS_I(inode)->delegation);
834 if (delegation == NULL)
836 if (stateid != NULL &&
837 !clp->cl_mvops->match_stateid(&delegation->stateid, stateid))
839 nfs_mark_return_delegation(server, delegation);
842 nfs_delegation_run_state_manager(clp);
849 static struct inode *
850 nfs_delegation_find_inode_server(struct nfs_server *server,
851 const struct nfs_fh *fhandle)
853 struct nfs_delegation *delegation;
854 struct inode *freeme, *res = NULL;
856 list_for_each_entry_rcu(delegation, &server->delegations, super_list) {
857 spin_lock(&delegation->lock);
858 if (delegation->inode != NULL &&
859 nfs_compare_fh(fhandle, &NFS_I(delegation->inode)->fh) == 0) {
860 freeme = igrab(delegation->inode);
861 if (freeme && nfs_sb_active(freeme->i_sb))
863 spin_unlock(&delegation->lock);
871 return ERR_PTR(-EAGAIN);
873 spin_unlock(&delegation->lock);
875 return ERR_PTR(-ENOENT);
879 * nfs_delegation_find_inode - retrieve the inode associated with a delegation
880 * @clp: client state handle
881 * @fhandle: filehandle from a delegation recall
883 * Returns pointer to inode matching "fhandle," or NULL if a matching inode
886 struct inode *nfs_delegation_find_inode(struct nfs_client *clp,
887 const struct nfs_fh *fhandle)
889 struct nfs_server *server;
893 list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
894 res = nfs_delegation_find_inode_server(server, fhandle);
895 if (res != ERR_PTR(-ENOENT)) {
901 return ERR_PTR(-ENOENT);
904 static void nfs_delegation_mark_reclaim_server(struct nfs_server *server)
906 struct nfs_delegation *delegation;
908 list_for_each_entry_rcu(delegation, &server->delegations, super_list) {
910 * If the delegation may have been admin revoked, then we
913 if (test_bit(NFS_DELEGATION_TEST_EXPIRED, &delegation->flags))
915 set_bit(NFS_DELEGATION_NEED_RECLAIM, &delegation->flags);
920 * nfs_delegation_mark_reclaim - mark all delegations as needing to be reclaimed
921 * @clp: nfs_client to process
924 void nfs_delegation_mark_reclaim(struct nfs_client *clp)
926 struct nfs_server *server;
929 list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
930 nfs_delegation_mark_reclaim_server(server);
935 * nfs_delegation_reap_unclaimed - reap unclaimed delegations after reboot recovery is done
936 * @clp: nfs_client to process
939 void nfs_delegation_reap_unclaimed(struct nfs_client *clp)
941 struct nfs_delegation *delegation;
942 struct nfs_server *server;
947 list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
948 list_for_each_entry_rcu(delegation, &server->delegations,
950 if (test_bit(NFS_DELEGATION_INODE_FREEING,
951 &delegation->flags) ||
952 test_bit(NFS_DELEGATION_RETURNING,
953 &delegation->flags) ||
954 test_bit(NFS_DELEGATION_NEED_RECLAIM,
955 &delegation->flags) == 0)
957 if (!nfs_sb_active(server->super))
958 break; /* continue in outer loop */
959 inode = nfs_delegation_grab_inode(delegation);
962 nfs_sb_deactive(server->super);
965 delegation = nfs_start_delegation_return_locked(NFS_I(inode));
967 if (delegation != NULL) {
968 delegation = nfs_detach_delegation(NFS_I(inode),
970 if (delegation != NULL)
971 nfs_free_delegation(delegation);
974 nfs_sb_deactive(server->super);
982 static inline bool nfs4_server_rebooted(const struct nfs_client *clp)
984 return (clp->cl_state & (BIT(NFS4CLNT_CHECK_LEASE) |
985 BIT(NFS4CLNT_LEASE_EXPIRED) |
986 BIT(NFS4CLNT_SESSION_RESET))) != 0;
989 static void nfs_mark_test_expired_delegation(struct nfs_server *server,
990 struct nfs_delegation *delegation)
992 if (delegation->stateid.type == NFS4_INVALID_STATEID_TYPE)
994 clear_bit(NFS_DELEGATION_NEED_RECLAIM, &delegation->flags);
995 set_bit(NFS_DELEGATION_TEST_EXPIRED, &delegation->flags);
996 set_bit(NFS4CLNT_DELEGATION_EXPIRED, &server->nfs_client->cl_state);
999 static void nfs_inode_mark_test_expired_delegation(struct nfs_server *server,
1000 struct inode *inode)
1002 struct nfs_delegation *delegation;
1005 delegation = rcu_dereference(NFS_I(inode)->delegation);
1007 nfs_mark_test_expired_delegation(server, delegation);
1012 static void nfs_delegation_mark_test_expired_server(struct nfs_server *server)
1014 struct nfs_delegation *delegation;
1016 list_for_each_entry_rcu(delegation, &server->delegations, super_list)
1017 nfs_mark_test_expired_delegation(server, delegation);
1021 * nfs_mark_test_expired_all_delegations - mark all delegations for testing
1022 * @clp: nfs_client to process
1024 * Iterates through all the delegations associated with this server and
1025 * marks them as needing to be checked for validity.
1027 void nfs_mark_test_expired_all_delegations(struct nfs_client *clp)
1029 struct nfs_server *server;
1032 list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
1033 nfs_delegation_mark_test_expired_server(server);
1038 * nfs_test_expired_all_delegations - test all delegations for a client
1039 * @clp: nfs_client to process
1041 * Helper for handling "recallable state revoked" status from server.
1043 void nfs_test_expired_all_delegations(struct nfs_client *clp)
1045 nfs_mark_test_expired_all_delegations(clp);
1046 nfs4_schedule_state_manager(clp);
1050 nfs_delegation_test_free_expired(struct inode *inode,
1051 nfs4_stateid *stateid,
1052 const struct cred *cred)
1054 struct nfs_server *server = NFS_SERVER(inode);
1055 const struct nfs4_minor_version_ops *ops = server->nfs_client->cl_mvops;
1060 status = ops->test_and_free_expired(server, stateid, cred);
1061 if (status == -NFS4ERR_EXPIRED || status == -NFS4ERR_BAD_STATEID)
1062 nfs_remove_bad_delegation(inode, stateid);
1066 * nfs_reap_expired_delegations - reap expired delegations
1067 * @clp: nfs_client to process
1069 * Iterates through all the delegations associated with this server and
1070 * checks if they have may have been revoked. This function is usually
1071 * expected to be called in cases where the server may have lost its
1074 void nfs_reap_expired_delegations(struct nfs_client *clp)
1076 struct nfs_delegation *delegation;
1077 struct nfs_server *server;
1078 struct inode *inode;
1079 const struct cred *cred;
1080 nfs4_stateid stateid;
1084 list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
1085 list_for_each_entry_rcu(delegation, &server->delegations,
1087 if (test_bit(NFS_DELEGATION_INODE_FREEING,
1088 &delegation->flags) ||
1089 test_bit(NFS_DELEGATION_RETURNING,
1090 &delegation->flags) ||
1091 test_bit(NFS_DELEGATION_TEST_EXPIRED,
1092 &delegation->flags) == 0)
1094 if (!nfs_sb_active(server->super))
1095 break; /* continue in outer loop */
1096 inode = nfs_delegation_grab_inode(delegation);
1097 if (inode == NULL) {
1099 nfs_sb_deactive(server->super);
1102 cred = get_cred_rcu(delegation->cred);
1103 nfs4_stateid_copy(&stateid, &delegation->stateid);
1104 clear_bit(NFS_DELEGATION_TEST_EXPIRED, &delegation->flags);
1106 nfs_delegation_test_free_expired(inode, &stateid, cred);
1108 if (nfs4_server_rebooted(clp)) {
1109 nfs_inode_mark_test_expired_delegation(server,inode);
1111 nfs_sb_deactive(server->super);
1115 nfs_sb_deactive(server->super);
1123 void nfs_inode_find_delegation_state_and_recover(struct inode *inode,
1124 const nfs4_stateid *stateid)
1126 struct nfs_client *clp = NFS_SERVER(inode)->nfs_client;
1127 struct nfs_delegation *delegation;
1131 delegation = rcu_dereference(NFS_I(inode)->delegation);
1133 nfs4_stateid_match_other(&delegation->stateid, stateid)) {
1134 nfs_mark_test_expired_delegation(NFS_SERVER(inode), delegation);
1139 nfs4_schedule_state_manager(clp);
1143 * nfs_delegations_present - check for existence of delegations
1144 * @clp: client state handle
1146 * Returns one if there are any nfs_delegation structures attached
1147 * to this nfs_client.
1149 int nfs_delegations_present(struct nfs_client *clp)
1151 struct nfs_server *server;
1155 list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
1156 if (!list_empty(&server->delegations)) {
1165 * nfs4_refresh_delegation_stateid - Update delegation stateid seqid
1166 * @dst: stateid to refresh
1167 * @inode: inode to check
1169 * Returns "true" and updates "dst->seqid" * if inode had a delegation
1170 * that matches our delegation stateid. Otherwise "false" is returned.
1172 bool nfs4_refresh_delegation_stateid(nfs4_stateid *dst, struct inode *inode)
1174 struct nfs_delegation *delegation;
1180 delegation = rcu_dereference(NFS_I(inode)->delegation);
1181 if (delegation != NULL &&
1182 nfs4_stateid_match_other(dst, &delegation->stateid)) {
1183 dst->seqid = delegation->stateid.seqid;
1192 * nfs4_copy_delegation_stateid - Copy inode's state ID information
1193 * @inode: inode to check
1194 * @flags: delegation type requirement
1195 * @dst: stateid data structure to fill in
1196 * @cred: optional argument to retrieve credential
1198 * Returns "true" and fills in "dst->data" * if inode had a delegation,
1199 * otherwise "false" is returned.
1201 bool nfs4_copy_delegation_stateid(struct inode *inode, fmode_t flags,
1202 nfs4_stateid *dst, const struct cred **cred)
1204 struct nfs_inode *nfsi = NFS_I(inode);
1205 struct nfs_delegation *delegation;
1208 flags &= FMODE_READ|FMODE_WRITE;
1210 delegation = rcu_dereference(nfsi->delegation);
1211 ret = nfs4_is_valid_delegation(delegation, flags);
1213 nfs4_stateid_copy(dst, &delegation->stateid);
1214 nfs_mark_delegation_referenced(delegation);
1216 *cred = get_cred(delegation->cred);
1223 * nfs4_delegation_flush_on_close - Check if we must flush file on close
1224 * @inode: inode to check
1226 * This function checks the number of outstanding writes to the file
1227 * against the delegation 'space_limit' field to see if
1228 * the spec requires us to flush the file on close.
1230 bool nfs4_delegation_flush_on_close(const struct inode *inode)
1232 struct nfs_inode *nfsi = NFS_I(inode);
1233 struct nfs_delegation *delegation;
1237 delegation = rcu_dereference(nfsi->delegation);
1238 if (delegation == NULL || !(delegation->type & FMODE_WRITE))
1240 if (atomic_long_read(&nfsi->nrequests) < delegation->pagemod_limit)