myri10ge: fix management of >4kB allocated pages

Fix management of allocated physical pages when the architecture
page size is not 4kB since the firmware cannot cross 4K boundary.
Signed-off-by: Brice Goglin <brice@myri.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

drivers/net/myri10ge/myri10ge.c

@@ -905,6 +905,14 @@ myri10ge_alloc_rx_pages(struct myri10ge_priv *mgp, struct myri10ge_rx_buf *rx,
 		    (rx->page_offset + bytes <= MYRI10GE_ALLOC_SIZE)) {
 			/* we can use part of previous page */
 			get_page(rx->page);
+#if MYRI10GE_ALLOC_SIZE > 4096
+			/* Firmware cannot cross 4K boundary.. */
+			if ((rx->page_offset >> 12) !=
+			    ((rx->page_offset + bytes - 1) >> 12)) {
+				rx->page_offset =
+				    (rx->page_offset + bytes) & ~4095;
+			}
+#endif
 		} else {
 			/* we need a new page */
 			page =