30 static bool is_empty_dir(struct ctl_table_header *head)  in is_empty_dir()  argument
32 	return head->ctl_table[0].child == sysctl_mount_point;  in is_empty_dir()
78 static int insert_links(struct ctl_table_header *head);
107 	struct ctl_table_header *head;  in find_entry()  local
118 		head = ctl_node->header;  in find_entry()
119 		entry = &head->ctl_table[ctl_node - head->node];  in find_entry()
128 			*phead = head;  in find_entry()
135 static int insert_entry(struct ctl_table_header *head, struct ctl_table *entry)  in insert_entry()  argument
137 	struct rb_node *node = &head->node[entry - head->ctl_table].node;  in insert_entry()
138 	struct rb_node **p = &head->parent->root.rb_node;  in insert_entry()
163 			sysctl_print_dir(head->parent);  in insert_entry()
170 	rb_insert_color(node, &head->parent->root);  in insert_entry()
174 static void erase_entry(struct ctl_table_header *head, struct ctl_table *entry)  in erase_entry()  argument
176 	struct rb_node *node = &head->node[entry - head->ctl_table].node;  in erase_entry()
178 	rb_erase(node, &head->parent->root);  in erase_entry()
181 static void init_header(struct ctl_table_header *head,  in init_header()  argument
185 	head->ctl_table = table;  in init_header()
186 	head->ctl_table_arg = table;  in init_header()
187 	head->used = 0;  in init_header()
188 	head->count = 1;  in init_header()
189 	head->nreg = 1;  in init_header()
190 	head->unregistering = NULL;  in init_header()
191 	head->root = root;  in init_header()
192 	head->set = set;  in init_header()
193 	head->parent = NULL;  in init_header()
194 	head->node = node;  in init_header()
195 	INIT_HLIST_HEAD(&head->inodes);  in init_header()
199 			node->header = head;  in init_header()
203 static void erase_header(struct ctl_table_header *head)  in erase_header()  argument
206 	for (entry = head->ctl_table; entry->procname; entry++)  in erase_header()
207 		erase_entry(head, entry);  in erase_header()
265 static void proc_sys_prune_dcache(struct ctl_table_header *head)  in proc_sys_prune_dcache()  argument
274 		node = hlist_first_rcu(&head->inodes);  in proc_sys_prune_dcache()
334 static struct ctl_table_header *sysctl_head_grab(struct ctl_table_header *head)  in sysctl_head_grab()  argument
336 	BUG_ON(!head);  in sysctl_head_grab()
338 	if (!use_table(head))  in sysctl_head_grab()
339 		head = ERR_PTR(-ENOENT);  in sysctl_head_grab()
341 	return head;  in sysctl_head_grab()
344 static void sysctl_head_finish(struct ctl_table_header *head)  in sysctl_head_finish()  argument
346 	if (!head)  in sysctl_head_finish()
349 	unuse_table(head);  in sysctl_head_finish()
366 	struct ctl_table_header *head;  in lookup_entry()  local
370 	entry = find_entry(&head, dir, name, namelen);  in lookup_entry()
371 	if (entry && use_table(head))  in lookup_entry()
372 		*phead = head;  in lookup_entry()
394 	struct ctl_table_header *head = NULL;  in first_entry()  local
402 		head = ctl_node->header;  in first_entry()
403 		entry = &head->ctl_table[ctl_node - head->node];  in first_entry()
405 	*phead = head;  in first_entry()
411 	struct ctl_table_header *head = *phead;  in next_entry()  local
413 	struct ctl_node *ctl_node = &head->node[entry - head->ctl_table];  in next_entry()
416 	unuse_table(head);  in next_entry()
420 	head = NULL;  in next_entry()
422 		head = ctl_node->header;  in next_entry()
423 		entry = &head->ctl_table[ctl_node - head->node];  in next_entry()
425 	*phead = head;  in next_entry()
445 static int sysctl_perm(struct ctl_table_header *head, struct ctl_table *table, int op)  in sysctl_perm()  argument
447 	struct ctl_table_root *root = head->root;  in sysctl_perm()
451 		mode = root->permissions(head, table);  in sysctl_perm()
459 		struct ctl_table_header *head, struct ctl_table *table)  in proc_sys_make_inode()  argument
461 	struct ctl_table_root *root = head->root;  in proc_sys_make_inode()
474 	if (unlikely(head->unregistering)) {  in proc_sys_make_inode()
480 	ei->sysctl = head;  in proc_sys_make_inode()
482 	hlist_add_head_rcu(&ei->sysctl_inodes, &head->inodes);  in proc_sys_make_inode()
483 	head->count++;  in proc_sys_make_inode()
496 		if (is_empty_dir(head))  in proc_sys_make_inode()
501 		root->set_ownership(head, table, &inode->i_uid, &inode->i_gid);  in proc_sys_make_inode()
507 void proc_sys_evict_inode(struct inode *inode, struct ctl_table_header *head)  in proc_sys_evict_inode()  argument
511 	if (!--head->count)  in proc_sys_evict_inode()
512 		kfree_rcu(head, rcu);  in proc_sys_evict_inode()
518 	struct ctl_table_header *head = PROC_I(inode)->sysctl;  in grab_header()  local
519 	if (!head)  in grab_header()
520 		head = &sysctl_table_root.default_set.dir.header;  in grab_header()
521 	return sysctl_head_grab(head);  in grab_header()
527 	struct ctl_table_header *head = grab_header(dir);  in proc_sys_lookup()  local
536 	if (IS_ERR(head))  in proc_sys_lookup()
537 		return ERR_CAST(head);  in proc_sys_lookup()
539 	ctl_dir = container_of(head, struct ctl_dir, header);  in proc_sys_lookup()
553 	inode = proc_sys_make_inode(dir->i_sb, h ? h : head, p);  in proc_sys_lookup()
563 	sysctl_head_finish(head);  in proc_sys_lookup()
571 	struct ctl_table_header *head = grab_header(inode);  in proc_sys_call_handler()  local
576 	if (IS_ERR(head))  in proc_sys_call_handler()
577 		return PTR_ERR(head);  in proc_sys_call_handler()
584 	if (sysctl_perm(head, table, write ? MAY_WRITE : MAY_READ))  in proc_sys_call_handler()
598 	sysctl_head_finish(head);  in proc_sys_call_handler()
617 	struct ctl_table_header *head = grab_header(inode);  in proc_sys_open()  local
621 	if (IS_ERR(head))  in proc_sys_open()
622 		return PTR_ERR(head);  in proc_sys_open()
627 	sysctl_head_finish(head);  in proc_sys_open()
635 	struct ctl_table_header *head = grab_header(inode);  in proc_sys_poll()  local
641 	if (IS_ERR(head))  in proc_sys_poll()
659 	sysctl_head_finish(head);  in proc_sys_poll()
666 				struct ctl_table_header *head,  in proc_sys_fill_cache()  argument
687 			inode = proc_sys_make_inode(dir->d_sb, head, table);  in proc_sys_fill_cache()
715 				    struct ctl_table_header *head,  in proc_sys_link_fill_cache()  argument
720 	head = sysctl_head_grab(head);  in proc_sys_link_fill_cache()
721 	if (IS_ERR(head))  in proc_sys_link_fill_cache()
725 	if (sysctl_follow_link(&head, &table))  in proc_sys_link_fill_cache()
728 	ret = proc_sys_fill_cache(file, ctx, head, table);  in proc_sys_link_fill_cache()
730 	sysctl_head_finish(head);  in proc_sys_link_fill_cache()
734 static int scan(struct ctl_table_header *head, struct ctl_table *table,  in scan()  argument
744 		res = proc_sys_link_fill_cache(file, ctx, head, table);  in scan()
746 		res = proc_sys_fill_cache(file, ctx, head, table);  in scan()
756 	struct ctl_table_header *head = grab_header(file_inode(file));  in proc_sys_readdir()  local
762 	if (IS_ERR(head))  in proc_sys_readdir()
763 		return PTR_ERR(head);  in proc_sys_readdir()
765 	ctl_dir = container_of(head, struct ctl_dir, header);  in proc_sys_readdir()
779 	sysctl_head_finish(head);  in proc_sys_readdir()
789 	struct ctl_table_header *head;  in proc_sys_permission()  local
797 	head = grab_header(inode);  in proc_sys_permission()
798 	if (IS_ERR(head))  in proc_sys_permission()
799 		return PTR_ERR(head);  in proc_sys_permission()
805 		error = sysctl_perm(head, table, mask & ~MAY_NOT_BLOCK);  in proc_sys_permission()
807 	sysctl_head_finish(head);  in proc_sys_permission()
832 	struct ctl_table_header *head = grab_header(inode);  in proc_sys_getattr()  local
835 	if (IS_ERR(head))  in proc_sys_getattr()
836 		return PTR_ERR(head);  in proc_sys_getattr()
842 	sysctl_head_finish(head);  in proc_sys_getattr()
903 	struct ctl_table_header *head;  in proc_sys_compare()  local
916 	head = rcu_dereference(PROC_I(inode)->sysctl);  in proc_sys_compare()
917 	return !head || !sysctl_is_seen(head);  in proc_sys_compare()
929 	struct ctl_table_header *head;  in find_subdir()  local
932 	entry = find_entry(&head, dir, name, namelen);  in find_subdir()
937 	return container_of(head, struct ctl_dir, header);  in find_subdir()
1044 	struct ctl_table_header *head;  in sysctl_follow_link()  local
1060 		head = NULL;  in sysctl_follow_link()
1061 		entry = find_entry(&head, dir, procname, strlen(procname));  in sysctl_follow_link()
1063 		if (entry && use_table(head)) {  in sysctl_follow_link()
1065 			*phead = head;  in sysctl_follow_link()
1184 	struct ctl_table_header *head;  in get_links()  local
1190 		link = find_entry(&head, dir, procname, strlen(procname));  in get_links()
1203 		link = find_entry(&head, dir, procname, strlen(procname));  in get_links()
1204 		head->nreg++;  in get_links()
1209 static int insert_links(struct ctl_table_header *head)  in insert_links()  argument
1216 	if (head->set == root_set)  in insert_links()
1219 	core_parent = xlate_dir(root_set, head->parent);  in insert_links()
1223 	if (get_links(core_parent, head->ctl_table, head->root))  in insert_links()
1229 	links = new_links(core_parent, head->ctl_table, head->root);  in insert_links()
1237 	if (get_links(core_parent, head->ctl_table, head->root)) {  in insert_links()