[PATCH] staging: media: atomisp: Use kmap_local_page() in hmm_set()

From: "Fabio M. De Francesco" <fmdefrancesco@gmail.com>
To: Mauro Carvalho Chehab <mchehab@kernel.org>,
	Sakari Ailus <sakari.ailus@linux.intel.com>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Hans Verkuil <hverkuil-cisco@xs4all.nl>,
	Tsuchiya Yuto <kitakar@gmail.com>,
	Martiros Shakhzadyan <vrzh@vrzh.net>,
	Hans de Goede <hdegoede@redhat.com>,
	linux-media@vger.kernel.org, linux-staging@lists.linux.dev,
	linux-kernel@vger.kernel.org, Ira Weiny <ira.weiny@intel.com>,
	outreachy@lists.linux.dev
Cc: "Fabio M. De Francesco" <fmdefrancesco@gmail.com>
Subject: [PATCH] staging: media: atomisp: Use kmap_local_page() in hmm_set()
Date: Wed, 13 Apr 2022 23:22:10 +0200	[thread overview]
Message-ID: <20220413212210.18494-1-fmdefrancesco@gmail.com> (raw)

The use of kmap() is being deprecated in favor of kmap_local_page()
where it is feasible. In file pci/hmm/hmm.c, function hmm_set() calls
kmap() / kunmap() where kmap_local_page() can instead do the mapping.

With kmap_local_page(), the mapping is per thread, CPU local and not
globally visible. Therefore, hmm_set()() is a function where the use
of kmap_local_page() in place of kmap() is correctly suited.

Convert the calls of kmap() / kunmap() to kmap_local_page() /
kunmap_local().

Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
---
 drivers/staging/media/atomisp/pci/hmm/hmm.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/staging/media/atomisp/pci/hmm/hmm.c b/drivers/staging/media/atomisp/pci/hmm/hmm.c
index 6394385b6637..46ac082cd3f1 100644
--- a/drivers/staging/media/atomisp/pci/hmm/hmm.c
+++ b/drivers/staging/media/atomisp/pci/hmm/hmm.c
@@ -563,7 +563,7 @@ int hmm_set(ia_css_ptr virt, int c, unsigned int bytes)
 		idx = (virt - bo->start) >> PAGE_SHIFT;
 		offset = (virt - bo->start) - (idx << PAGE_SHIFT);
 
-		des = (char *)kmap(bo->page_obj[idx].page) + offset;
+		des = (char *)kmap_local_page(bo->page_obj[idx].page) + offset;
 
 		if ((bytes + offset) >= PAGE_SIZE) {
 			len = PAGE_SIZE - offset;
@@ -579,7 +579,7 @@ int hmm_set(ia_css_ptr virt, int c, unsigned int bytes)
 
 		clflush_cache_range(des, len);
 
-		kunmap(bo->page_obj[idx].page);
+		kunmap_local(des);
 	}
 
 	return 0;
-- 
2.34.1

