[PATCH 2/4] Staging: ks7010: hostif: Fix multiple use of arguments in SME queue macros.

From: Quytelda Kahja
Date: Fri Feb 16 2018 - 21:25:41 EST


Use GCC extensions to prevent macro arguments from accidentally being evaluated
multiple times when the macro is called.

Signed-off-by: Quytelda Kahja <quytelda@xxxxxxxxxxx>
---
drivers/staging/ks7010/ks_hostif.c | 19 +++++++++++++------
1 file changed, 13 insertions(+), 6 deletions(-)

diff --git a/drivers/staging/ks7010/ks_hostif.c b/drivers/staging/ks7010/ks_hostif.c
index 975dbbb3abd0..30c9592b3a00 100644
--- a/drivers/staging/ks7010/ks_hostif.c
+++ b/drivers/staging/ks7010/ks_hostif.c
@@ -22,12 +22,19 @@
#include <net/iw_handler.h> /* New driver API */

/* macro */
-#define inc_smeqhead(priv) \
- (priv->sme_i.qhead = (priv->sme_i.qhead + 1) % SME_EVENT_BUFF_SIZE)
-#define inc_smeqtail(priv) \
- (priv->sme_i.qtail = (priv->sme_i.qtail + 1) % SME_EVENT_BUFF_SIZE)
-#define cnt_smeqbody(priv) \
- (((priv->sme_i.qtail + SME_EVENT_BUFF_SIZE) - (priv->sme_i.qhead)) % SME_EVENT_BUFF_SIZE)
+#define inc_smeqhead(priv) \
+ ({ typeof(priv) priv_ = (priv); \
+ unsigned int next_qhead = priv_->sme_i.qhead + 1; \
+ priv_->sme_i.qhead = next_qhead % SME_EVENT_BUFF_SIZE; })
+#define inc_smeqtail(priv) \
+ ({ typeof(priv) priv_ = (priv); \
+ unsigned int next_qtail = priv_->sme_i.qtail + 1; \
+ priv_->sme_i.qtail = next_qtail % SME_EVENT_BUFF_SIZE; })
+#define cnt_smeqbody(priv) \
+ ({ typeof(priv) priv_ = (priv); \
+ unsigned int left_cnt = \
+ priv_->sme_i.qtail + SME_EVENT_BUFF_SIZE; \
+ (left_cnt - (priv_->sme_i.qhead)) % SME_EVENT_BUFF_SIZE; })

#define KS_WLAN_MEM_FLAG (GFP_ATOMIC)

--
2.16.1