1 files changed, 135 insertions, 0 deletions

diff --git a/arch/arm64/mm/flush.c b/arch/arm64/mm/flush.c
new file mode 100644
index 000000000000..c144adb1682f
--- /dev/null
+++ b/arch/arm64/mm/flush.c
@@ -0,0 +1,135 @@
+/*
+ * Based on arch/arm/mm/flush.c
+ *
+ * Copyright (C) 1995-2002 Russell King
+ * Copyright (C) 2012 ARM Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/export.h>
+#include <linux/mm.h>
+#include <linux/pagemap.h>
+
+#include <asm/cacheflush.h>
+#include <asm/cachetype.h>
+#include <asm/tlbflush.h>
+
+#include "mm.h"
+
+void flush_cache_mm(struct mm_struct *mm)
+{
+}
+
+void flush_cache_range(struct vm_area_struct *vma, unsigned long start,
+                       unsigned long end)
+{
+        if (vma->vm_flags & VM_EXEC)
+                __flush_icache_all();
+}
+
+void flush_cache_page(struct vm_area_struct *vma, unsigned long user_addr,
+                      unsigned long pfn)
+{
+}
+
+static void flush_ptrace_access(struct vm_area_struct *vma, struct page *page,
+                                unsigned long uaddr, void *kaddr,
+                                unsigned long len)
+{
+        if (vma->vm_flags & VM_EXEC) {
+                unsigned long addr = (unsigned long)kaddr;
+                if (icache_is_aliasing()) {
+                        __flush_dcache_area(kaddr, len);
+                        __flush_icache_all();
+                } else {
+                        flush_icache_range(addr, addr + len);
+                }
+        }
+}
+
+/*
+ * Copy user data from/to a page which is mapped into a different processes
+ * address space.  Really, we want to allow our "user space" model to handle
+ * this.
+ *
+ * Note that this code needs to run on the current CPU.
+ */
+void copy_to_user_page(struct vm_area_struct *vma, struct page *page,
+                       unsigned long uaddr, void *dst, const void *src,
+                       unsigned long len)
+{
+#ifdef CONFIG_SMP
+        preempt_disable();
+#endif
+        memcpy(dst, src, len);
+        flush_ptrace_access(vma, page, uaddr, dst, len);
+#ifdef CONFIG_SMP
+        preempt_enable();
+#endif
+}
+
+void __flush_dcache_page(struct page *page)
+{
+        __flush_dcache_area(page_address(page), PAGE_SIZE);
+}
+
+void __sync_icache_dcache(pte_t pte, unsigned long addr)
+{
+        unsigned long pfn;
+        struct page *page;
+
+        pfn = pte_pfn(pte);
+        if (!pfn_valid(pfn))
+                return;
+
+        page = pfn_to_page(pfn);
+        if (!test_and_set_bit(PG_dcache_clean, &page->flags)) {
+                __flush_dcache_page(page);
+                __flush_icache_all();
+        } else if (icache_is_aivivt()) {
+                __flush_icache_all();
+        }
+}
+
+/*
+ * Ensure cache coherency between kernel mapping and userspace mapping of this
+ * page.
+ */
+void flush_dcache_page(struct page *page)
+{
+        struct address_space *mapping;
+
+        /*
+         * The zero page is never written to, so never has any dirty cache
+         * lines, and therefore never needs to be flushed.
+         */
+        if (page == ZERO_PAGE(0))
+                return;
+
+        mapping = page_mapping(page);
+        if (mapping && mapping_mapped(mapping)) {
+                __flush_dcache_page(page);
+                __flush_icache_all();
+                set_bit(PG_dcache_clean, &page->flags);
+        } else {
+                clear_bit(PG_dcache_clean, &page->flags);
+        }
+}
+EXPORT_SYMBOL(flush_dcache_page);
+
+/*
+ * Additional functions defined in assembly.
+ */
+EXPORT_SYMBOL(flush_cache_all);
+EXPORT_SYMBOL(flush_icache_range);