[ARM] clearpage: provide our own clear_user_highpage()

For similar reasons as copy_user_page(), we want to avoid the
additional kmap_atomic if it's unnecessary.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 10 insertions, 10 deletions

diff --git a/arch/arm/mm/copypage-feroceon.c b/arch/arm/mm/copypage-feroceon.c
index edd71686b8df..c3651b2939c7 100644
--- a/arch/arm/mm/copypage-feroceon.c
+++ b/arch/arm/mm/copypage-feroceon.c
@@ -79,12 +79,11 @@ void feroceon_copy_user_highpage(struct page *to, struct page *from,
 	kunmap_atomic(kto, KM_USER0);
 }
 
-void __attribute__((naked))
-feroceon_clear_user_page(void *kaddr, unsigned long vaddr)
+void feroceon_clear_user_highpage(struct page *page, unsigned long vaddr)
 {
+	void *kaddr = kmap_atomic(page, KM_USER0);
 	asm("\
-	stmfd	sp!, {r4-r7, lr}		\n\
-	mov	r1, %0				\n\
+	mov	r1, %1				\n\
 	mov	r2, #0				\n\
 	mov	r3, #0				\n\
 	mov	r4, #0				\n\
@@ -93,19 +92,20 @@ feroceon_clear_user_page(void *kaddr, unsigned long vaddr)
 	mov	r7, #0				\n\
 	mov	ip, #0				\n\
 	mov	lr, #0				\n\
-1:	stmia	r0, {r2-r7, ip, lr}		\n\
+1:	stmia	%0, {r2-r7, ip, lr}		\n\
 	subs	r1, r1, #1			\n\
-	mcr	p15, 0, r0, c7, c14, 1		@ clean and invalidate D line\n\
+	mcr	p15, 0, %0, c7, c14, 1		@ clean and invalidate D line\n\
 	add	r0, r0, #32			\n\
 	bne	1b				\n\
-	mcr	p15, 0, r1, c7, c10, 4		@ drain WB\n\
-	ldmfd	sp!, {r4-r7, pc}"
+	mcr	p15, 0, r1, c7, c10, 4		@ drain WB"
 	:
-	: "I" (PAGE_SIZE / 32));
+	: "r" (kaddr), "I" (PAGE_SIZE / 32)
+	: "r1", "r2", "r3", "r4", "r5", "r6", "r7", "ip", "lr");
+	kunmap_atomic(kaddr, KM_USER0);
 }
 
 struct cpu_user_fns feroceon_user_fns __initdata = {
-	.cpu_clear_user_page	= feroceon_clear_user_page,
+	.cpu_clear_user_highpage = feroceon_clear_user_highpage,
 	.cpu_copy_user_highpage	= feroceon_copy_user_highpage,
 };