104 	f->tail = 0;  in msnd_fifo_alloc()
116 	f->len = f->tail = f->head = 0;  in msnd_fifo_make_empty()
127 		if (f->head <= f->tail) {  in msnd_fifo_write_io()
129 			if (nwritten > f->n - f->tail)  in msnd_fifo_write_io()
130 				nwritten = f->n - f->tail;  in msnd_fifo_write_io()
133 			nwritten = f->head - f->tail;  in msnd_fifo_write_io()
138 		memcpy_fromio(f->data + f->tail, buf, nwritten);  in msnd_fifo_write_io()
143 		f->tail += nwritten;  in msnd_fifo_write_io()
144 		f->tail %= f->n;  in msnd_fifo_write_io()
158 		if (f->head <= f->tail) {  in msnd_fifo_write()
160 			if (nwritten > f->n - f->tail)  in msnd_fifo_write()
161 				nwritten = f->n - f->tail;  in msnd_fifo_write()
164 			nwritten = f->head - f->tail;  in msnd_fifo_write()
169 		memcpy(f->data + f->tail, buf, nwritten);  in msnd_fifo_write()
174 		f->tail += nwritten;  in msnd_fifo_write()
175 		f->tail %= f->n;  in msnd_fifo_write()
189 		if (f->tail <= f->head) {  in msnd_fifo_read_io()
195 			nread = f->tail - f->head;  in msnd_fifo_read_io()
220 		if (f->tail <= f->head) {  in msnd_fifo_read()
226 			nread = f->tail - f->head;  in msnd_fifo_read()