[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>
diff --git a/arch/arm/mm/copypage-xsc3.c b/arch/arm/mm/copypage-xsc3.c
index caa697c..0e7cb32 100644
--- a/arch/arm/mm/copypage-xsc3.c
+++ b/arch/arm/mm/copypage-xsc3.c
@@ -87,26 +87,27 @@
* r0 = destination
* r1 = virtual user address of ultimate destination page
*/
-void __attribute__((naked))
-xsc3_mc_clear_user_page(void *kaddr, unsigned long vaddr)
+void xsc3_mc_clear_user_highpage(struct page *page, unsigned long vaddr)
{
+ void *kaddr = kmap_atomic(page, KM_USER0);
asm("\
- mov r1, %0 \n\
+ mov r1, %1 \n\
mov r2, #0 \n\
mov r3, #0 \n\
-1: mcr p15, 0, r0, c7, c6, 1 @ invalidate line\n\
- strd r2, [r0], #8 \n\
- strd r2, [r0], #8 \n\
- strd r2, [r0], #8 \n\
- strd r2, [r0], #8 \n\
+1: mcr p15, 0, %0, c7, c6, 1 @ invalidate line\n\
+ strd r2, [%0], #8 \n\
+ strd r2, [%0], #8 \n\
+ strd r2, [%0], #8 \n\
+ strd r2, [%0], #8 \n\
subs r1, r1, #1 \n\
- bne 1b \n\
- mov pc, lr"
+ bne 1b"
:
- : "I" (PAGE_SIZE / 32));
+ : "r" (kaddr), "I" (PAGE_SIZE / 32)
+ : "r1", "r2", "r3");
+ kunmap_atomic(kaddr, KM_USER0);
}
struct cpu_user_fns xsc3_mc_user_fns __initdata = {
- .cpu_clear_user_page = xsc3_mc_clear_user_page,
+ .cpu_clear_user_highpage = xsc3_mc_clear_user_highpage,
.cpu_copy_user_highpage = xsc3_mc_copy_user_highpage,
};