From cc1f6563a92ced0889775d0587316d725b6e1a68 Mon Sep 17 00:00:00 2001
From: Guo Ren <guoren@linux.alibaba.com>
Date: Mon, 27 Jan 2020 19:57:29 +0800
Subject: csky: Optimize abiv2 copy_to_user_page with VM_EXEC

Only when vma is for VM_EXEC, we need sync dcache & icache. eg:
 - gdb ptrace modify user space instruction code area.

Add VM_EXEC condition to reduce unnecessary cache flush.

The abiv1 cpus' cache are all VIPT, so we still need to deal with
dcache aliasing problem. But there is optimized way to use cache
color, just like what's done in arch/csky/abiv1/inc/abi/page.h.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
---
 arch/csky/abiv2/inc/abi/cacheflush.h | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

(limited to 'arch/csky')

diff --git a/arch/csky/abiv2/inc/abi/cacheflush.h b/arch/csky/abiv2/inc/abi/cacheflush.h
index acd7c6c55d61..28b7c3233175 100644
--- a/arch/csky/abiv2/inc/abi/cacheflush.h
+++ b/arch/csky/abiv2/inc/abi/cacheflush.h
@@ -37,7 +37,9 @@ static inline void flush_dcache_page(struct page *page)
 #define copy_to_user_page(vma, page, vaddr, dst, src, len) \
 do { \
 	memcpy(dst, src, len); \
-	cache_wbinv_range((unsigned long)dst, (unsigned long)dst + len); \
+	if (vma->vm_flags & VM_EXEC) \
+		cache_wbinv_range((unsigned long)dst, \
+				  (unsigned long)dst + len); \
 } while (0)
 #define copy_from_user_page(vma, page, vaddr, dst, src, len) \
 	memcpy(dst, src, len)
-- 
cgit v1.2.3