110 	xs_suspend_active--;  in xs_suspend_exit()
119 	req->type = req->msg.type;  in xs_request_enter()
129 	if (req->type == XS_TRANSACTION_START && !req->user_req)  in xs_request_enter()
142 	xs_state_users--;  in xs_request_exit()
143 	if ((req->type == XS_TRANSACTION_START && req->msg.type == XS_ERROR) ||  in xs_request_exit()
144 	    (req->type == XS_TRANSACTION_END && !req->user_req &&  in xs_request_exit()
145 	     !WARN_ON_ONCE(req->msg.type == XS_ERROR &&  in xs_request_exit()
146 			   !strcmp(req->body, "ENOENT"))))  in xs_request_exit()
147 		xs_state_users--;  in xs_request_exit()
159 		if (i == ARRAY_SIZE(xsd_errors) - 1) {  in get_error()
194 	if (req->state == xb_req_state_got_reply || !xenbus_ok()) {  in test_reply()
195 		/* read req->state before all other fields */  in test_reply()
200 	/* Make sure to reread req->state each time. */  in test_reply()
209 		wait_event(req->wq, test_reply(req));  in read_reply()
213 			 * If we are in the process of being shut-down there is  in read_reply()
214 			 * no point of trying to contact XenBus - it is either  in read_reply()
218 			return ERR_PTR(-EIO);  in read_reply()
219 		if (req->err)  in read_reply()
220 			return ERR_PTR(req->err);  in read_reply()
222 	} while (req->state != xb_req_state_got_reply);  in read_reply()
224 	return req->body;  in read_reply()
231 	req->msg = *msg;  in xs_send()
232 	req->err = 0;  in xs_send()
233 	req->state = xb_req_state_queued;  in xs_send()
234 	init_waitqueue_head(&req->wq);  in xs_send()
237 	req->caller_req_id = req->msg.req_id;  in xs_send()
238 	req->msg.req_id = xs_request_enter(req);  in xs_send()
241 	list_add_tail(&req->list, &xb_write_list);  in xs_send()
257 	msg->type = req->msg.type;  in xs_wait_for_reply()
258 	msg->len = req->msg.len;  in xs_wait_for_reply()
261 	if (req->state == xb_req_state_queued ||  in xs_wait_for_reply()
262 	    req->state == xb_req_state_wait_reply)  in xs_wait_for_reply()
263 		req->state = xb_req_state_aborted;  in xs_wait_for_reply()
273 	wake_up(&req->wq);  in xs_wake_up()
283 		return -ENOMEM;  in xenbus_dev_request_and_reply()
286 	vec->iov_len = msg->len;  in xenbus_dev_request_and_reply()
287 	vec->iov_base = msg + 1;  in xenbus_dev_request_and_reply()
289 	req->vec = vec;  in xenbus_dev_request_and_reply()
290 	req->num_vecs = 1;  in xenbus_dev_request_and_reply()
291 	req->cb = xenbus_dev_queue_reply;  in xenbus_dev_request_and_reply()
292 	req->par = par;  in xenbus_dev_request_and_reply()
293 	req->user_req = true;  in xenbus_dev_request_and_reply()
316 		return ERR_PTR(-ENOMEM);  in xs_talkv()
318 	req->vec = iovec;  in xs_talkv()
319 	req->num_vecs = num_vecs;  in xs_talkv()
320 	req->cb = xs_wake_up;  in xs_talkv()
321 	req->user_req = false;  in xs_talkv()
342 		return ERR_PTR(-err);  in xs_talkv()
349 		return ERR_PTR(-EINVAL);  in xs_talkv()
376 static unsigned int count_strings(const char *strings, unsigned int len)  in count_strings()  argument
378 	unsigned int num;  in count_strings()  local
381 	for (p = strings, num = 0; p < strings + len; p += strlen(p) + 1)  in count_strings()
382 		num++;  in count_strings()
384 	return num;  in count_strings()
396 	return (!buffer) ? ERR_PTR(-ENOMEM) : buffer;  in join()
399 static char **split(char *strings, unsigned int len, unsigned int *num)  in split()  argument
403 	/* Count the strings. */  in split()
404 	*num = count_strings(strings, len);  in split()
407 	ret = kmalloc(*num * sizeof(char *) + len, GFP_NOIO | __GFP_HIGH);  in split()
409 		kfree(strings);  in split()
410 		return ERR_PTR(-ENOMEM);  in split()
412 	memcpy(&ret[*num], strings, len);  in split()
413 	kfree(strings);  in split()
415 	strings = (char *)&ret[*num];  in split()
416 	for (p = strings, *num = 0; p < strings + len; p += strlen(p) + 1)  in split()
417 		ret[(*num)++] = p;  in split()
423 			const char *dir, const char *node, unsigned int *num)  in xenbus_directory()  argument
425 	char *strings, *path;  in xenbus_directory()  local
432 	strings = xs_single(t, XS_DIRECTORY, path, &len);  in xenbus_directory()
434 	if (IS_ERR(strings))  in xenbus_directory()
435 		return (char **)strings;  in xenbus_directory()
437 	return split(strings, len, num);  in xenbus_directory()
477  * Returns -err on failure.
545 	t->id = simple_strtoul(id_str, NULL, 0);  in xenbus_transaction_start()
567 /* Single read and scanf: returns -errno or num scanned. */
585 		return -ERANGE;  in xenbus_scanf()
605 /* Single printf and write: returns -errno or 0. */
618 		return -ENOMEM;  in xenbus_printf()
628 /* Takes tuples of names, scanf-style args, and void **, NULL terminated. */
648 				ret = -EINVAL;  in xenbus_gather()
699 	if (count_strings(event->body, event->len) != 2) {  in xs_watch_msg()
701 		return -EINVAL;  in xs_watch_msg()
703 	event->path = (const char *)event->body;  in xs_watch_msg()
704 	event->token = (const char *)strchr(event->body, '\0') + 1;  in xs_watch_msg()
707 	event->handle = find_watch(event->token);  in xs_watch_msg()
708 	if (event->handle != NULL &&  in xs_watch_msg()
709 			(!event->handle->will_handle ||  in xs_watch_msg()
710 			 event->handle->will_handle(event->handle,  in xs_watch_msg()
711 				 event->path, event->token))) {  in xs_watch_msg()
713 		list_add_tail(&event->list, &watch_events);  in xs_watch_msg()
714 		event->handle->nr_pending++;  in xs_watch_msg()
728  * control/platform-feature-xs_reset_watches.
755 				  "platform-feature-xs_reset_watches", 0))  in xs_reset_watches()
759 	if (err && err != -EEXIST)  in xs_reset_watches()
772 	watch->nr_pending = 0;  in register_xenbus_watch()
778 	list_add(&watch->list, &watches);  in register_xenbus_watch()
781 	err = xs_watch(watch->node, token);  in register_xenbus_watch()
785 		list_del(&watch->list);  in register_xenbus_watch()
807 	list_del(&watch->list);  in unregister_xenbus_watch()
810 	err = xs_unwatch(watch->node, token);  in unregister_xenbus_watch()
812 		pr_warn("Failed to release watch %s: %i\n", watch->node, err);  in unregister_xenbus_watch()
818 	if (current->pid != xenwatch_pid)  in unregister_xenbus_watch()
823 	if (watch->nr_pending) {  in unregister_xenbus_watch()
825 			if (event->handle != watch)  in unregister_xenbus_watch()
827 			list_del(&event->list);  in unregister_xenbus_watch()
830 		watch->nr_pending = 0;  in unregister_xenbus_watch()
834 	if (current->pid != xenwatch_pid)  in unregister_xenbus_watch()
861 		xs_watch(watch->node, token);  in xs_resume()
879 	xenwatch_pid = current->pid;  in xenwatch_thread()
894 			list_del(&event->list);  in xenwatch_thread()
895 			event->handle->nr_pending--;  in xenwatch_thread()
900 			event->handle->callback(event->handle, event->path,  in xenwatch_thread()
901 						event->token);  in xenwatch_thread()
925 		wake_up(&req->wq);  in xs_reboot_notify()
927 		wake_up(&req->wq);  in xs_reboot_notify()