Re: [PATCH v2] kfifo: don't include dma-mapping.h in kfifo.h

From: Jiri Slaby
Date: Wed Oct 23 2024 - 02:30:45 EST


On 23. 10. 24, 7:53, Christoph Hellwig wrote:
Nothing in kfifo.h directly needs dma-mapping.h, only two macros
use DMA_MAPPING_ERROR when actually instantiated. Drop the
dma-mapping.h include to reduce include bloat.

Add an explicity <linux/io.h> include to drivers/mailbox/omap-mailbox.c
as that file uses __raw_readl and __raw_writel through a complicated
include chain involving <linux/dma-mapping.h>

Fixes: d52b761e4b1a ("kfifo: add kfifo_dma_out_prepare_mapped()")
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---

Changes since v1:
- improve the commit log

drivers/mailbox/omap-mailbox.c | 1 +
include/linux/kfifo.h | 1 -
samples/kfifo/dma-example.c | 1 +
3 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/mailbox/omap-mailbox.c b/drivers/mailbox/omap-mailbox.c
index 6797770474a5..680243751d62 100644
--- a/drivers/mailbox/omap-mailbox.c
+++ b/drivers/mailbox/omap-mailbox.c
@@ -15,6 +15,7 @@
#include <linux/slab.h>
#include <linux/kfifo.h>

Funnily enough, this driver does not use kfifo since:
commit 3f58c1f4206f37d0af4595a9046c76016334b301
Author: Andrew Davis <afd@xxxxxx>
Date: Wed Apr 10 08:59:42 2024 -0500

mailbox: omap: Remove kernel FIFO message queuing

#include <linux/err.h>
+#include <linux/io.h>

So this should have been revealed at that point (while removing kfifo.h in that commit too).

Perhaps Andrew can remove the include now?

thanks,
--
js
suse labs