29  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
68 	return ((prod - cons) <= XENSTORE_RING_SIZE);  in check_indexes()
75 	*len = XENSTORE_RING_SIZE - MASK_XENSTORE_IDX(prod);  in get_output_chunk()
76 	if ((XENSTORE_RING_SIZE - (prod - cons)) < *len)  in get_output_chunk()
77 		*len = XENSTORE_RING_SIZE - (prod - cons);  in get_output_chunk()
85 	*len = XENSTORE_RING_SIZE - MASK_XENSTORE_IDX(cons);  in get_input_chunk()
86 	if ((prod - cons) < *len)  in get_input_chunk()
87 		*len = prod - cons;  in get_input_chunk()
95 	return (intf->req_prod - intf->req_cons) != XENSTORE_RING_SIZE &&  in xb_data_to_write()
100  * xb_write - low level write
104  * Returns number of bytes written or -err.
116 		/* Read indexes, then verify. */  in xb_write()
117 		cons = intf->req_cons;  in xb_write()
118 		prod = intf->req_prod;  in xb_write()
120 			intf->req_cons = intf->req_prod = 0;  in xb_write()
121 			return -EIO;  in xb_write()
129 		dst = get_output_chunk(cons, prod, intf->req, &avail);  in xb_write()
137 		len -= avail;  in xb_write()
142 		intf->req_prod += avail;  in xb_write()
145 		if (prod <= intf->req_cons)  in xb_write()
155 	return (intf->rsp_cons != intf->rsp_prod);  in xb_data_to_read()
168 		/* Read indexes, then verify. */  in xb_read()
169 		cons = intf->rsp_cons;  in xb_read()
170 		prod = intf->rsp_prod;  in xb_read()
175 			intf->rsp_cons = intf->rsp_prod = 0;  in xb_read()
176 			return -EIO;  in xb_read()
179 		src = get_input_chunk(cons, prod, intf->rsp, &avail);  in xb_read()
185 		/* Must read data /after/ reading the producer index. */  in xb_read()
190 		len -= avail;  in xb_read()
193 		/* Other side must not see free space until we've copied out */  in xb_read()
195 		intf->rsp_cons += avail;  in xb_read()
198 		if (intf->rsp_prod - cons >= XENSTORE_RING_SIZE)  in xb_read()
216 		unsigned int read;  in process_msg()  member
225 		state.read = 0;  in process_msg()
229 		 * A partial read across s/r leaves us out of sync with  in process_msg()
246 		if (state.read != sizeof(state.msg)) {  in process_msg()
247 			err = xb_read((void *)&state.msg + state.read,  in process_msg()
248 				      sizeof(state.msg) - state.read);  in process_msg()
250 				goto out;  in process_msg()
251 			state.read += err;  in process_msg()
252 			if (state.read != sizeof(state.msg))  in process_msg()
255 				err = -EINVAL;  in process_msg()
256 				goto out;  in process_msg()
266 			return -ENOMEM;  in process_msg()
269 			state.body = state.watch->body;  in process_msg()
273 		state.read = 0;  in process_msg()
276 	err = xb_read(state.body + state.read, state.msg.len - state.read);  in process_msg()
278 		goto out;  in process_msg()
280 	state.read += err;  in process_msg()
281 	if (state.read != state.msg.len)  in process_msg()
287 		state.watch->len = state.msg.len;  in process_msg()
290 		err = -ENOENT;  in process_msg()
293 			if (req->msg.req_id == state.msg.req_id) {  in process_msg()
294 				list_del(&req->list);  in process_msg()
301 			goto out;  in process_msg()
303 		if (req->state == xb_req_state_wait_reply) {  in process_msg()
304 			req->msg.req_id = req->caller_req_id;  in process_msg()
305 			req->msg.type = state.msg.type;  in process_msg()
306 			req->msg.len = state.msg.len;  in process_msg()
307 			req->body = state.body;  in process_msg()
310 			req->state = xb_req_state_got_reply;  in process_msg()
311 			req->cb(req);  in process_msg()
322  out:  in process_msg()
349 		state.idx = -1;  in process_writes()
353 	if (state.req->state == xb_req_state_aborted)  in process_writes()
356 	while (state.idx < state.req->num_vecs) {  in process_writes()
358 			base = &state.req->msg;  in process_writes()
359 			len = sizeof(state.req->msg);  in process_writes()
361 			base = state.req->vec[state.idx].iov_base;  in process_writes()
362 			len = state.req->vec[state.idx].iov_len;  in process_writes()
364 		err = xb_write(base + state.written, len - state.written);  in process_writes()
369 			goto out;  in process_writes()
375 	list_del(&state.req->list);  in process_writes()
376 	state.req->state = xb_req_state_wait_reply;  in process_writes()
377 	list_add_tail(&state.req->list, &xs_reply_list);  in process_writes()
380  out:  in process_writes()
386 	state.req->msg.type = XS_ERROR;  in process_writes()
387 	state.req->err = err;  in process_writes()
388 	list_del(&state.req->list);  in process_writes()
389 	if (state.req->state == xb_req_state_aborted)  in process_writes()
394 		state.req->state = xb_req_state_got_reply;  in process_writes()
395 		wake_up(&state.req->wq);  in process_writes()
419 		if (err == -ENOMEM)  in xenbus_thread()
436  * xb_init_comms - Set up interrupt handler off store event channel.
442 	if (intf->req_prod != intf->req_cons)  in xb_init_comms()
444 		       intf->req_cons, intf->req_prod);  in xb_init_comms()
446 	if (intf->rsp_prod != intf->rsp_cons) {  in xb_init_comms()
448 			intf->rsp_cons, intf->rsp_prod);  in xb_init_comms()
451 			intf->rsp_cons = intf->rsp_prod;  in xb_init_comms()