sh: Wire up clear_user_highpage().
With the kmap_coherent() API in place, this is trivial to implement,
and lets us avoid the cache flush in certain cases.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
diff --git a/arch/sh/mm/pg-sh4.c b/arch/sh/mm/pg-sh4.c
index 25f5c6f..ede6dd1 100644
--- a/arch/sh/mm/pg-sh4.c
+++ b/arch/sh/mm/pg-sh4.c
@@ -9,6 +9,8 @@
#include <linux/mm.h>
#include <linux/mutex.h>
#include <linux/fs.h>
+#include <linux/highmem.h>
+#include <linux/module.h>
#include <asm/mmu_context.h>
#include <asm/cacheflush.h>
@@ -79,6 +81,27 @@
}
}
+void copy_user_highpage(struct page *to, struct page *from,
+ unsigned long vaddr, struct vm_area_struct *vma)
+{
+ void *vfrom, *vto;
+
+ __set_bit(PG_mapped, &to->flags);
+
+ vto = kmap_atomic(to, KM_USER1);
+ vfrom = kmap_coherent(from, vaddr);
+ copy_page(vto, vfrom);
+ kunmap_coherent(vfrom);
+
+ if (((vaddr ^ (unsigned long)vto) & CACHE_ALIAS))
+ __flush_wback_region(vto, PAGE_SIZE);
+
+ kunmap_atomic(vto, KM_USER1);
+ /* Make sure this page is cleared on other CPU's too before using it */
+ smp_wmb();
+}
+EXPORT_SYMBOL(copy_user_highpage);
+
/*
* For SH-4, we have our own implementation for ptep_get_and_clear
*/