iwlwifi: provide RX page order

When the pages are to be used by front-end, it may need
to know the page order, provide it.

Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
diff --git a/drivers/net/wireless/iwlwifi/iwl-trans.h b/drivers/net/wireless/iwlwifi/iwl-trans.h
index fca5fec..ce878b9 100644
--- a/drivers/net/wireless/iwlwifi/iwl-trans.h
+++ b/drivers/net/wireless/iwlwifi/iwl-trans.h
@@ -274,6 +274,7 @@
 	struct page *_page;
 	int _offset;
 	bool _page_stolen;
+	u32 _rx_page_order;
 	unsigned int truesize;
 };
 
@@ -294,6 +295,11 @@
 	return r->_page;
 }
 
+static inline void iwl_free_rxb(struct iwl_rx_cmd_buffer *r)
+{
+	__free_pages(r->_page, r->_rx_page_order);
+}
+
 #define MAX_NO_RECLAIM_CMDS	6
 
 #define IWL_MASK(lo, hi) ((1 << (hi)) | ((1 << (hi)) - (1 << (lo))))