1 // SPDX-License-Identifier: GPL-2.0
5  * (c) 2015 - Jeff Layton <jeff.layton@primarydata.com>
7  * An nfsd_file object is a per-file collection of open state that binds
9  *   - a struct file *
10  *   - a user credential
11  *   - a network namespace
12  *   - a read-ahead context
13  *   - monitoring for writeback errors
15  * nfsd_file objects are reference-counted. Consumers acquire a new
21  *  * non-garbage-collected: When a consumer wants to precisely control
22  *    the lifetime of a file's open state, it acquires a non-garbage-
26  *  * garbage-collected: When a consumer does not control the lifetime
27  *    of open state, it acquires a garbage-collected nfsd_file. The
29  *    during which it may be re-used.
83 	if (!uid_eq(c1->fsuid, c2->fsuid))  in nfsd_match_cred()
85 	if (!gid_eq(c1->fsgid, c2->fsgid))  in nfsd_match_cred()
87 	if (c1->group_info == NULL || c2->group_info == NULL)  in nfsd_match_cred()
88 		return c1->group_info == c2->group_info;  in nfsd_match_cred()
89 	if (c1->group_info->ngroups != c2->group_info->ngroups)  in nfsd_match_cred()
91 	for (i = 0; i < c1->group_info->ngroups; i++) {  in nfsd_match_cred()
92 		if (!gid_eq(c1->group_info->gid[i], c2->group_info->gid[i]))  in nfsd_match_cred()
124 	put_cred(nf->nf_cred);  in nfsd_file_slab_free()
140 	if (!refcount_inc_not_zero(&nfm->nfm_ref))  in nfsd_file_mark_get()
148 	if (refcount_dec_and_test(&nfm->nfm_ref)) {  in nfsd_file_mark_put()
149 		fsnotify_destroy_mark(&nfm->nfm_mark, nfsd_file_fsnotify_group);  in nfsd_file_mark_put()
150 		fsnotify_put_mark(&nfm->nfm_mark);  in nfsd_file_mark_put()
185 		fsnotify_init_mark(&new->nfm_mark, nfsd_file_fsnotify_group);  in nfsd_file_mark_find_or_create()
186 		new->nfm_mark.mask = FS_ATTRIB|FS_DELETE_SELF;  in nfsd_file_mark_find_or_create()
187 		refcount_set(&new->nfm_ref, 1);  in nfsd_file_mark_find_or_create()
189 		err = fsnotify_add_inode_mark(&new->nfm_mark, inode, 0);  in nfsd_file_mark_find_or_create()
197 		 * mark->group will be NULL. Thus, we can't let the nfm_ref  in nfsd_file_mark_find_or_create()
203 			fsnotify_put_mark(&new->nfm_mark);  in nfsd_file_mark_find_or_create()
204 	} while (unlikely(err == -EEXIST));  in nfsd_file_mark_find_or_create()
220 	INIT_LIST_HEAD(&nf->nf_lru);  in nfsd_file_alloc()
221 	INIT_LIST_HEAD(&nf->nf_gc);  in nfsd_file_alloc()
222 	nf->nf_birthtime = ktime_get();  in nfsd_file_alloc()
223 	nf->nf_file = NULL;  in nfsd_file_alloc()
224 	nf->nf_cred = get_current_cred();  in nfsd_file_alloc()
225 	nf->nf_net = net;  in nfsd_file_alloc()
226 	nf->nf_flags = want_gc ?  in nfsd_file_alloc()
229 	nf->nf_inode = inode;  in nfsd_file_alloc()
230 	refcount_set(&nf->nf_ref, 1);  in nfsd_file_alloc()
231 	nf->nf_may = need;  in nfsd_file_alloc()
232 	nf->nf_mark = NULL;  in nfsd_file_alloc()
237  * nfsd_file_check_write_error - check for writeback errors on a file
246 	struct file *file = nf->nf_file;  in nfsd_file_check_write_error()
248 	if ((file->f_mode & FMODE_WRITE) &&  in nfsd_file_check_write_error()
249 	    filemap_check_wb_err(file->f_mapping, READ_ONCE(file->f_wb_err)))  in nfsd_file_check_write_error()
250 		nfsd_reset_write_verifier(net_generic(nf->nf_net, nfsd_net_id));  in nfsd_file_check_write_error()
257 	rhltable_remove(&nfsd_file_rhltable, &nf->nf_rlist,  in nfsd_file_hash_remove()
264 	if (test_and_clear_bit(NFSD_FILE_HASHED, &nf->nf_flags)) {  in nfsd_file_unhash()
274 	s64 age = ktime_to_ms(ktime_sub(ktime_get(), nf->nf_birthtime));  in nfsd_file_free()
282 	if (nf->nf_mark)  in nfsd_file_free()
283 		nfsd_file_mark_put(nf->nf_mark);  in nfsd_file_free()
284 	if (nf->nf_file) {  in nfsd_file_free()
286 		nfsd_filp_close(nf->nf_file);  in nfsd_file_free()
293 	if (WARN_ON_ONCE(!list_empty(&nf->nf_lru)))  in nfsd_file_free()
296 	call_rcu(&nf->nf_rcu, nfsd_file_slab_free);  in nfsd_file_free()
302 	struct file *file = nf->nf_file;  in nfsd_file_check_writeback()
306 	if (!(file->f_mode & FMODE_WRITE))  in nfsd_file_check_writeback()
311 	 * On others, there is no need to wait for writeback.  in nfsd_file_check_writeback()
313 	if (!(file_inode(file)->i_sb->s_export_op->flags & EXPORT_OP_FLUSH_ON_CLOSE))  in nfsd_file_check_writeback()
316 	mapping = file->f_mapping;  in nfsd_file_check_writeback()
324 	set_bit(NFSD_FILE_REFERENCED, &nf->nf_flags);  in nfsd_file_lru_add()
325 	if (list_lru_add_obj(&nfsd_file_lru, &nf->nf_lru)) {  in nfsd_file_lru_add()
334 	if (list_lru_del_obj(&nfsd_file_lru, &nf->nf_lru)) {  in nfsd_file_lru_remove()
344 	if (nf && refcount_inc_not_zero(&nf->nf_ref))  in nfsd_file_get()
350  * nfsd_file_put - put the reference to a nfsd_file
353  * Put a reference to a nfsd_file. In the non-GC case, we just put the
363 	if (test_bit(NFSD_FILE_GC, &nf->nf_flags) &&  in nfsd_file_put()
364 	    test_bit(NFSD_FILE_HASHED, &nf->nf_flags)) {  in nfsd_file_put()
369 		if (refcount_dec_not_one(&nf->nf_ref))  in nfsd_file_put()
375 			if (test_bit(NFSD_FILE_HASHED, &nf->nf_flags)) {  in nfsd_file_put()
389 	if (refcount_dec_and_test(&nf->nf_ref))  in nfsd_file_put()
394  * nfsd_file_put_local - put nfsd_file reference and arm nfsd_serv_put in caller
403 	struct net *net = nf->nf_net;  in nfsd_file_put_local()
410  * nfsd_file_file - get the backing file of an nfsd_file
418 	return nf->nf_file;  in nfsd_file_file()
428 		list_del_init(&nf->nf_gc);  in nfsd_file_dispose_list()
434  * nfsd_file_dispose_list_delayed - move list of dead files to net's freeme list
438  * be disposed of by the per-net garbage collector.
446 		struct nfsd_net *nn = net_generic(nf->nf_net, nfsd_net_id);  in nfsd_file_dispose_list_delayed()
447 		struct nfsd_fcache_disposal *l = nn->fcache_disposal;  in nfsd_file_dispose_list_delayed()
449 		spin_lock(&l->lock);  in nfsd_file_dispose_list_delayed()
450 		list_move_tail(&nf->nf_gc, &l->freeme);  in nfsd_file_dispose_list_delayed()
451 		spin_unlock(&l->lock);  in nfsd_file_dispose_list_delayed()
452 		svc_wake_up(nn->nfsd_serv);  in nfsd_file_dispose_list_delayed()
457  * nfsd_file_net_dispose - deal with nfsd_files waiting to be disposed.
462  * a per-net-ns queue.  This function completes the disposal, either
467 	struct nfsd_fcache_disposal *l = nn->fcache_disposal;  in nfsd_file_net_dispose()
469 	if (!list_empty(&l->freeme)) {  in nfsd_file_net_dispose()
473 		spin_lock(&l->lock);  in nfsd_file_net_dispose()
474 		for (i = 0; i < 8 && !list_empty(&l->freeme); i++)  in nfsd_file_net_dispose()
475 			list_move(l->freeme.next, &dispose);  in nfsd_file_net_dispose()
476 		spin_unlock(&l->lock);  in nfsd_file_net_dispose()
477 		if (!list_empty(&l->freeme))  in nfsd_file_net_dispose()
481 			svc_wake_up(nn->nfsd_serv);  in nfsd_file_net_dispose()
487  * nfsd_file_lru_cb - Examine an entry on the LRU list
505 	WARN_ON_ONCE(!test_bit(NFSD_FILE_GC, &nf->nf_flags));  in nfsd_file_lru_cb()
517 	if (test_and_clear_bit(NFSD_FILE_REFERENCED, &nf->nf_flags)) {  in nfsd_file_lru_cb()
526 	if (!refcount_dec_and_test(&nf->nf_ref)) {  in nfsd_file_lru_cb()
528 		list_lru_isolate(lru, &nf->nf_lru);  in nfsd_file_lru_cb()
534 	list_lru_isolate(lru, &nf->nf_lru);  in nfsd_file_lru_cb()
535 	list_add(&nf->nf_gc, head);  in nfsd_file_lru_cb()
583  * nfsd_file_cond_queue - conditionally unhash and queue a nfsd_file
585  * @dispose: private list to queue successfully-put objects
609 	if (refcount_sub_and_test(decrement, &nf->nf_ref)) {  in nfsd_file_cond_queue()
610 		list_add(&nf->nf_gc, dispose);  in nfsd_file_cond_queue()
622  * undesirable behavior (e.g. spurious silly-renames when reexporting NFS).
629  * so we leave it up to the caller whether it wants to wait or not.
641 		if (!test_bit(NFSD_FILE_GC, &nf->nf_flags))  in nfsd_file_queue_for_close()
649  * nfsd_file_close_inode - attempt a delayed close of a nfsd_file
667  * nfsd_file_close_inode_sync - attempt to forcibly close a nfsd_file
673  * This is called from nfsd_rename and nfsd_unlink to avoid silly-renames
687 		list_del_init(&nf->nf_gc);  in nfsd_file_close_inode_sync()
699 	if (fl->c.flc_flags & FL_LEASE)  in nfsd_file_lease_notifier_call()
700 		nfsd_file_close_inode(file_inode(fl->c.flc_file));  in nfsd_file_lease_notifier_call()
718 	/* Should be no marks on non-regular files */  in nfsd_file_fsnotify_handle_event()
719 	if (!S_ISREG(inode->i_mode)) {  in nfsd_file_fsnotify_handle_event()
726 		if (inode->i_nlink)  in nfsd_file_fsnotify_handle_event()
753 	ret = -ENOMEM;  in nfsd_file_cache_init()
772 	nfsd_file_shrinker = shrinker_alloc(0, "nfsd-filecache");  in nfsd_file_cache_init()
774 		ret = -ENOMEM;  in nfsd_file_cache_init()
779 	nfsd_file_shrinker->count_objects = nfsd_file_lru_count;  in nfsd_file_cache_init()
780 	nfsd_file_shrinker->scan_objects = nfsd_file_lru_scan;  in nfsd_file_cache_init()
781 	nfsd_file_shrinker->seeks = 1;  in nfsd_file_cache_init()
823  * @net: net-namespace to shut down the cache (may be NULL)
842 			if (!net || nf->nf_net == net)  in __nfsd_file_cache_purge()
848 	} while (nf == ERR_PTR(-EAGAIN));  in __nfsd_file_cache_purge()
862 	spin_lock_init(&l->lock);  in nfsd_alloc_fcache_disposal()
863 	INIT_LIST_HEAD(&l->freeme);  in nfsd_alloc_fcache_disposal()
870 	nfsd_file_dispose_list(&l->freeme);  in nfsd_free_fcache_disposal()
878 	struct nfsd_fcache_disposal *l = nn->fcache_disposal;  in nfsd_free_fcache_disposal_net()
888 	nn->fcache_disposal = nfsd_alloc_fcache_disposal();  in nfsd_file_cache_start_net()
889 	return nn->fcache_disposal ? 0 : -ENOMEM;  in nfsd_file_cache_start_net()
893  * nfsd_file_cache_purge - Remove all cache items associated with @net
961 		if (nf->nf_may != need)  in nfsd_file_lookup_locked()
963 		if (nf->nf_net != net)  in nfsd_file_lookup_locked()
965 		if (!nfsd_match_cred(nf->nf_cred, cred))  in nfsd_file_lookup_locked()
967 		if (test_bit(NFSD_FILE_GC, &nf->nf_flags) != want_gc)  in nfsd_file_lookup_locked()
969 		if (test_bit(NFSD_FILE_HASHED, &nf->nf_flags) == 0)  in nfsd_file_lookup_locked()
980  * nfsd_file_is_cached - are there any cached open files for this inode?
1001 		if (test_bit(NFSD_FILE_GC, &nf->nf_flags)) {  in nfsd_file_is_cached()
1037 	inode = d_inode(fhp->fh_dentry);  in nfsd_file_do_acquire()
1050 			refcount_dec(&nf->nf_ref);  in nfsd_file_do_acquire()
1061 	spin_lock(&inode->i_lock);  in nfsd_file_do_acquire()
1064 		spin_unlock(&inode->i_lock);  in nfsd_file_do_acquire()
1070 	ret = rhltable_insert(&nfsd_file_rhltable, &nf->nf_rlist,  in nfsd_file_do_acquire()
1072 	spin_unlock(&inode->i_lock);  in nfsd_file_do_acquire()
1082 	wait_on_bit(&nf->nf_flags, NFSD_FILE_PENDING, TASK_UNINTERRUPTIBLE);  in nfsd_file_do_acquire()
1085 	if (!test_bit(NFSD_FILE_HASHED, &nf->nf_flags)) {  in nfsd_file_do_acquire()
1098 	status = nfserrno(nfsd_open_break_lease(file_inode(nf->nf_file), may_flags));  in nfsd_file_do_acquire()
1115 	nf->nf_mark = nfsd_file_mark_find_or_create(inode);  in nfsd_file_do_acquire()
1116 	if (nf->nf_mark) {  in nfsd_file_do_acquire()
1119 			nf->nf_file = file;  in nfsd_file_do_acquire()
1123 			ret = nfsd_open_verified(fhp, may_flags, &nf->nf_file);  in nfsd_file_do_acquire()
1124 			if (ret == -EOPENSTALE && stale_retry) {  in nfsd_file_do_acquire()
1128 						      &nf->nf_flags);  in nfsd_file_do_acquire()
1129 				if (refcount_dec_and_test(&nf->nf_ref))  in nfsd_file_do_acquire()
1144 	if (status != nfs_ok || inode->i_nlink == 0)  in nfsd_file_do_acquire()
1146 	clear_and_wake_up_bit(NFSD_FILE_PENDING, &nf->nf_flags);  in nfsd_file_do_acquire()
1151 	if (refcount_dec_and_test(&nf->nf_ref))  in nfsd_file_do_acquire()
1158  * nfsd_file_acquire_gc - Get a struct nfsd_file with an open file
1164  * The nfsd_file object returned by this API is reference-counted
1165  * and garbage-collected. The object is retained for a few
1167  * wants to re-use it.
1170  *   %nfs_ok - @pnf points to an nfsd_file with its reference
1184  * nfsd_file_acquire - Get a struct nfsd_file with an open file
1190  * The nfsd_file_object returned by this API is reference-counted
1191  * but not garbage-collected. The object is unhashed after the
1195  *   %nfs_ok - @pnf points to an nfsd_file with its reference
1209  * nfsd_file_acquire_local - Get a struct nfsd_file with an open file for localio
1218  * filehandle and credential.  No connection-based authorisation
1225  * The nfsd_file object returned by this API is reference-counted
1226  * and garbage-collected. The object is retained for a few
1228  * wants to re-use it.
1231  *   %nfs_ok - @pnf points to an nfsd_file with its reference
1256  * nfsd_file_acquire_opened - Get a struct nfsd_file using existing open file
1260  * @file: cached, already-open file (may be NULL)
1264  * and @file is non-NULL, use it to instantiate a new nfsd_file instead of
1268  *   %nfs_ok - @pnf points to an nfsd_file with its reference
1304 		count = atomic_read(&ht->nelems);  in nfsd_file_cache_stats_show()
1305 		tbl = rht_dereference_rcu(ht->tbl, ht);  in nfsd_file_cache_stats_show()
1306 		buckets = tbl->size;  in nfsd_file_cache_stats_show()
1331 		seq_printf(m, "mean age (ms): -\n");  in nfsd_file_cache_stats_show()