diff mbox series

[3.16-stable,03/14] drbd: avoid redefinition of BITS_PER_PAGE

Message ID 20170509100502.1358298-4-arnd@arndb.de
State New
Headers show
Series [3.16-stable,01/14] staging: r8192ee: prorperly format warning message | expand

Commit Message

Arnd Bergmann May 9, 2017, 10:04 a.m. UTC 
From: Lars Ellenberg <lars.ellenberg@linbit.com>


Commit 2630628b2dbc3fc320aafaf84836119e4e3d62f1 upstream.

Apparently we now implicitly get definitions for BITS_PER_PAGE and
BITS_PER_PAGE_MASK from the pid_namespace.h

Instead of renaming our defines, I chose to define only if not yet
defined, but to double check the value if already defined.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>

Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>

Signed-off-by: Jens Axboe <axboe@fb.com>

Signed-off-by: Arnd Bergmann <arnd@arndb.de>

---
 drivers/block/drbd/drbd_bitmap.c | 6 ++++++
 1 file changed, 6 insertions(+)

-- 
2.9.0
diff mbox series

Patch

diff --git a/drivers/block/drbd/drbd_bitmap.c b/drivers/block/drbd/drbd_bitmap.c
index 1aa29f8fdfe1..7c76f7270bec 100644
--- a/drivers/block/drbd/drbd_bitmap.c
+++ b/drivers/block/drbd/drbd_bitmap.c
@@ -478,8 +478,14 @@  void drbd_bm_cleanup(struct drbd_device *device)
  * this masks out the remaining bits.
  * Returns the number of bits cleared.
  */
+#ifndef BITS_PER_PAGE
 #define BITS_PER_PAGE		(1UL << (PAGE_SHIFT + 3))
 #define BITS_PER_PAGE_MASK	(BITS_PER_PAGE - 1)
+#else
+# if BITS_PER_PAGE != (1UL << (PAGE_SHIFT + 3))
+#  error "ambiguous BITS_PER_PAGE"
+# endif
+#endif
 #define BITS_PER_LONG_MASK	(BITS_PER_LONG - 1)
 static int bm_clear_surplus(struct drbd_bitmap *b)
 {