[PATCH 4.9 10/35] arch/arc: add copy_user_page() to <asm/page.h> to fix build error on ARC

From: Greg Kroah-Hartman
Date: Fri Jan 22 2021 - 09:22:39 EST

From: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>

[ Upstream commit 8a48c0a3360bf2bf4f40c980d0ec216e770e58ee ]

fs/dax.c uses copy_user_page() but ARC does not provide that interface,
resulting in a build error.

Provide copy_user_page() in <asm/page.h>.

../fs/dax.c: In function 'copy_cow_page_dax':
../fs/dax.c:702:2: error: implicit declaration of function 'copy_user_page'; did you mean 'copy_to_user_page'? [-Werror=implicit-function-declaration]

Reported-by: kernel test robot <lkp@xxxxxxxxx>
Signed-off-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
Cc: Vineet Gupta <vgupta@xxxxxxxxxxxx>
Cc: linux-snps-arc@xxxxxxxxxxxxxxxxxxx
Cc: Dan Williams <dan.j.williams@xxxxxxxxx>
#Acked-by: Vineet Gupta <vgupta@xxxxxxxxxxxx> # v1
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx>
Cc: Jan Kara <jack@xxxxxxx>
Cc: linux-fsdevel@xxxxxxxxxxxxxxx
Cc: linux-nvdimm@xxxxxxxxxxxx
#Reviewed-by: Ira Weiny <ira.weiny@xxxxxxxxx> # v2
Signed-off-by: Vineet Gupta <vgupta@xxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
arch/arc/include/asm/page.h | 1 +
1 file changed, 1 insertion(+)

diff --git a/arch/arc/include/asm/page.h b/arch/arc/include/asm/page.h
index ffb5f33475f19..f0f43eb709d2f 100644
--- a/arch/arc/include/asm/page.h
+++ b/arch/arc/include/asm/page.h
@@ -13,6 +13,7 @@
#ifndef __ASSEMBLY__

#define clear_page(paddr) memset((paddr), 0, PAGE_SIZE)
+#define copy_user_page(to, from, vaddr, pg) copy_page(to, from)
#define copy_page(to, from) memcpy((to), (from), PAGE_SIZE)

struct vm_area_struct;