kfifo API type safety
This patch enhances the type safety for the kfifo API. It is now safe
to put const data into a non const FIFO and the API will now generate a
compiler warning when reading from the fifo where the destination
address is pointing to a const variable.
As a side effect the kfifo_put() does now expect the value of an element
instead a pointer to the element. This was suggested Russell King. It
make the handling of the kfifo_put easier since there is no need to
create a helper variable for getting the address of a pointer or to pass
integers of different sizes.
IMHO the API break is okay, since there are currently only six users of
kfifo_put().
The code is also cleaner by kicking out the "if (0)" expressions.
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Stefani Seibold <stefani@seibold.net>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Hauke Mehrtens <hauke@hauke-m.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/samples/kfifo/bytestream-example.c b/samples/kfifo/bytestream-example.c
index cfe40ad..2fca916 100644
--- a/samples/kfifo/bytestream-example.c
+++ b/samples/kfifo/bytestream-example.c
@@ -64,7 +64,7 @@
/* put values into the fifo */
for (i = 0; i != 10; i++)
- kfifo_put(&test, &i);
+ kfifo_put(&test, i);
/* show the number of used elements */
printk(KERN_INFO "fifo len: %u\n", kfifo_len(&test));
@@ -85,7 +85,7 @@
kfifo_skip(&test);
/* put values into the fifo until is full */
- for (i = 20; kfifo_put(&test, &i); i++)
+ for (i = 20; kfifo_put(&test, i); i++)
;
printk(KERN_INFO "queue len: %u\n", kfifo_len(&test));