Thread (18 messages) 18 messages, 4 authors, 2018-03-26

Re: [PATCH v13 01/10] iomap: Use correct endian conversion function in mmio_writeXXbe

From: Luc Van Oostenryck <hidden>
Date: 2018-03-21 17:28:44
Also in: linux-arch, linux-crypto

On Wed, Mar 21, 2018 at 10:37:36AM -0600, Logan Gunthorpe wrote:
quoted hunk ↗ jump to hunk
The semantics of the iowriteXXbe() functions are to write a
value in CPU endianess to an IO register that is known by the
caller to be in Big Endian. The mmio_writeXXbe() macro, which
is called by iowriteXXbe(), should therefore use cpu_to_beXX()
instead of beXX_to_cpu().

Seeing both beXX_to_cpu() and cpu_to_beXX() are both functionally
implemented as either null operations or swabXX operations there
was no noticable bug here. But it is confusing for both developers
and code analysis tools alike.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Cc: Philippe Ombredanne <redacted>
Cc: Thomas Gleixner <redacted>
Cc: Kate Stewart <redacted>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Luc Van Oostenryck <redacted>
---
 lib/iomap.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/lib/iomap.c b/lib/iomap.c
index 541d926da95e..be120c13d6cc 100644
--- a/lib/iomap.c
+++ b/lib/iomap.c
@@ -106,8 +106,8 @@ EXPORT_SYMBOL(ioread32be);
 #endif
 
 #ifndef mmio_write16be
-#define mmio_write16be(val,port) __raw_writew(be16_to_cpu(val),port)
-#define mmio_write32be(val,port) __raw_writel(be32_to_cpu(val),port)
+#define mmio_write16be(val,port) __raw_writew(cpu_to_be16(val),port)
+#define mmio_write32be(val,port) __raw_writel(cpu_to_be32(val),port)
 #endif
 
 void iowrite8(u8 val, void __iomem *addr)
-- 
2.11.0
LGTM, feel free to add my
Reviewed-by: Luc Van Oostenryck <redacted>

-- Luc
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help