[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,
 };