38  *  The ids->rwsem must be taken when:
75 	int ids;  member
109  * @ids: ipc identifier set
112  * below ipc_mni) then initialise the keys hashtable and ids idr.
114 void ipc_init_ids(struct ipc_ids *ids)  in ipc_init_ids()  argument
116 	ids->in_use = 0;  in ipc_init_ids()
117 	ids->seq = 0;  in ipc_init_ids()
118 	init_rwsem(&ids->rwsem);  in ipc_init_ids()
119 	rhashtable_init(&ids->key_ht, &ipc_kht_params);  in ipc_init_ids()
120 	idr_init(&ids->ipcs_idr);  in ipc_init_ids()
121 	ids->max_idx = -1;  in ipc_init_ids()
122 	ids->last_idx = -1;  in ipc_init_ids()
124 	ids->next_id = -1;  in ipc_init_ids()
134  * @ids: ipc id table to iterate.
138 		int ids, int (*show)(struct seq_file *, void *))  in ipc_init_proc_interface()  argument
148 	iface->ids	= ids;  in ipc_init_proc_interface()
163  * @ids: ipc identifier set
171 static struct kern_ipc_perm *ipc_findkey(struct ipc_ids *ids, key_t key)  in ipc_findkey()  argument
175 	ipcp = rhashtable_lookup_fast(&ids->key_ht, &key,  in ipc_findkey()
201 static inline int ipc_idr_alloc(struct ipc_ids *ids, struct kern_ipc_perm *new)  in ipc_idr_alloc()  argument
206 	next_id = ids->next_id;  in ipc_idr_alloc()
207 	ids->next_id = -1;  in ipc_idr_alloc()
225 		max_idx = max(ids->in_use*3/2, ipc_min_cycle);  in ipc_idr_alloc()
229 		idx = idr_alloc_cyclic(&ids->ipcs_idr, NULL, 0, max_idx,  in ipc_idr_alloc()
238 			if (idx <= ids->last_idx) {  in ipc_idr_alloc()
239 				ids->seq++;  in ipc_idr_alloc()
240 				if (ids->seq >= ipcid_seq_max())  in ipc_idr_alloc()
241 					ids->seq = 0;  in ipc_idr_alloc()
243 			ids->last_idx = idx;  in ipc_idr_alloc()
245 			new->seq = ids->seq;  in ipc_idr_alloc()
250 			idr_replace(&ids->ipcs_idr, new, idx);  in ipc_idr_alloc()
254 		idx = idr_alloc(&ids->ipcs_idr, new, ipcid_to_idx(next_id),  in ipc_idr_alloc()
264  * @ids: ipc identifier set
266  * @limit: limit for the number of used ids
268  * Add an entry 'new' to the ipc ids idr. The permissions object is
277 int ipc_addid(struct ipc_ids *ids, struct kern_ipc_perm *new, int limit)  in ipc_addid()  argument
289 	if (ids->in_use >= limit)  in ipc_addid()
304 	idx = ipc_idr_alloc(ids, new);  in ipc_addid()
308 		err = rhashtable_insert_fast(&ids->key_ht, &new->khtnode,  in ipc_addid()
311 			idr_remove(&ids->ipcs_idr, idx);  in ipc_addid()
322 	ids->in_use++;  in ipc_addid()
323 	if (idx > ids->max_idx)  in ipc_addid()
324 		ids->max_idx = idx;  in ipc_addid()
331  * @ids: ipc identifier set
338 static int ipcget_new(struct ipc_namespace *ns, struct ipc_ids *ids,  in ipcget_new()  argument
343 	down_write(&ids->rwsem);  in ipcget_new()
345 	up_write(&ids->rwsem);  in ipcget_new()
385  * @ids: ipc identifier set
396 static int ipcget_public(struct ipc_namespace *ns, struct ipc_ids *ids,  in ipcget_public()  argument
407 	down_write(&ids->rwsem);  in ipcget_public()
408 	ipcp = ipc_findkey(ids, params->key);  in ipcget_public()
433 	up_write(&ids->rwsem);  in ipcget_public()
440  * @ids: ipc identifier set
446 static void ipc_kht_remove(struct ipc_ids *ids, struct kern_ipc_perm *ipcp)  in ipc_kht_remove()  argument
449 		rhashtable_remove_fast(&ids->key_ht, &ipcp->khtnode,  in ipc_kht_remove()
455  * @ids: ipc identifier set
461 void ipc_rmid(struct ipc_ids *ids, struct kern_ipc_perm *ipcp)  in ipc_rmid()  argument
465 	idr_remove(&ids->ipcs_idr, idx);  in ipc_rmid()
466 	ipc_kht_remove(ids, ipcp);  in ipc_rmid()
467 	ids->in_use--;  in ipc_rmid()
470 	if (unlikely(idx == ids->max_idx)) {  in ipc_rmid()
475 		} while (!idr_find(&ids->ipcs_idr, idx));  in ipc_rmid()
476 		ids->max_idx = idx;  in ipc_rmid()
482  * @ids: ipc identifier set
488 void ipc_set_key_private(struct ipc_ids *ids, struct kern_ipc_perm *ipcp)  in ipc_set_key_private()  argument
490 	ipc_kht_remove(ids, ipcp);  in ipc_set_key_private()
585  * @ids: ipc identifier set
588  * Look for an id in the ipc ids idr and return associated ipc object.
593 struct kern_ipc_perm *ipc_obtain_object_idr(struct ipc_ids *ids, int id)  in ipc_obtain_object_idr()  argument
598 	out = idr_find(&ids->ipcs_idr, idx);  in ipc_obtain_object_idr()
607  * @ids: ipc identifier set
616 struct kern_ipc_perm *ipc_obtain_object_check(struct ipc_ids *ids, int id)  in ipc_obtain_object_check()  argument
618 	struct kern_ipc_perm *out = ipc_obtain_object_idr(ids, id);  in ipc_obtain_object_check()
632  * @ids: ipc identifier set
639 int ipcget(struct ipc_namespace *ns, struct ipc_ids *ids,  in ipcget()  argument
643 		return ipcget_new(ns, ids, ops, params);  in ipcget()
645 		return ipcget_public(ns, ids, ops, params);  in ipcget()
671  * @ids:  the table of ids where to look for the ipc
689 					struct ipc_ids *ids, int id, int cmd,  in ipcctl_obtain_check()  argument
696 	ipcp = ipc_obtain_object_check(ids, id);  in ipcctl_obtain_check()
754 static struct kern_ipc_perm *sysvipc_find_ipc(struct ipc_ids *ids, loff_t pos,  in sysvipc_find_ipc()  argument
761 	for (id = 0; id < pos && total < ids->in_use; id++) {  in sysvipc_find_ipc()
762 		ipc = idr_find(&ids->ipcs_idr, id);  in sysvipc_find_ipc()
768 	if (total >= ids->in_use)  in sysvipc_find_ipc()
772 		ipc = idr_find(&ids->ipcs_idr, pos);  in sysvipc_find_ipc()
794 	return sysvipc_find_ipc(&iter->ns->ids[iface->ids], *pos, pos);  in sysvipc_proc_next()
805 	struct ipc_ids *ids;  in sysvipc_proc_start()  local
807 	ids = &iter->ns->ids[iface->ids];  in sysvipc_proc_start()
813 	down_read(&ids->rwsem);  in sysvipc_proc_start()
824 	return sysvipc_find_ipc(ids, *pos - 1, pos);  in sysvipc_proc_start()
832 	struct ipc_ids *ids;  in sysvipc_proc_stop()  local
838 	ids = &iter->ns->ids[iface->ids];  in sysvipc_proc_stop()
840 	up_read(&ids->rwsem);  in sysvipc_proc_stop()