X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=libbcachefs%2Ffifo.h;h=cdb272708a4bdacf94093a7c0351570189abf973;hb=1e574cb1aa07ab3a796c7d6c5501b96f3056ef4d;hp=085d828e6ed154e0cb7501a82edb201859655fdc;hpb=cef2f30ae2a25df41704b9b06fc13882d737cc27;p=bcachefs-tools-debian

diff --git a/libbcachefs/fifo.h b/libbcachefs/fifo.h
index 085d828..cdb2727 100644
--- a/libbcachefs/fifo.h
+++ b/libbcachefs/fifo.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef _BCACHEFS_FIFO_H
 #define _BCACHEFS_FIFO_H
 
@@ -12,7 +13,9 @@ struct {								\
 #define DECLARE_FIFO(type, name)	FIFO(type) name
 
 #define fifo_buf_size(fifo)						\
-	(roundup_pow_of_two((fifo)->size) * sizeof((fifo)->data[0]))
+	((fifo)->size							\
+	 ? roundup_pow_of_two((fifo)->size) * sizeof((fifo)->data[0])	\
+	 : 0)
 
 #define init_fifo(fifo, _size, _gfp)					\
 ({									\
@@ -98,7 +101,7 @@ do {									\
 ({									\
 	bool _r = !fifo_empty((fifo));					\
 	if (_r)								\
-		(i) = (fifo)->data[--(fifo)->back & (fifo)->mask]	\
+		(i) = (fifo)->data[--(fifo)->back & (fifo)->mask];	\
 	_r;								\
 })