Re: [linuxsh-dev] Different old_mmap behavior in 2.4.5 and 2.4.8

[NIIBE Y. <gn...@m1...>]

We need to implement
	MAP_SHARED: COLOUR_ALIGN
	MAP_PRIVATE: PAGE_ALIGN (Don't COLOUR_ALIGN)
	Others: don't care

I think that it's good to set default to COLOUR_ALIGN, as cache
works well.  Here's a patch.

	* arch/sh/kernel/sys_sh.c (arch_get_unmapped_area): Don't
	COLOUR_ALIGN when it comes with MAP_PRIVATE.

Index: arch/sh/kernel/sys_sh.c
===================================================================
RCS file: /cvsroot/linuxsh/kernel/arch/sh/kernel/sys_sh.c,v
retrieving revision 1.7
diff -u -r1.7 sys_sh.c
--- arch/sh/kernel/sys_sh.c	2001/08/03 23:50:59	1.7
+++ arch/sh/kernel/sys_sh.c	2001/09/13 01:11:11
@@ -68,7 +68,10 @@
 	if (!addr)
 		addr = TASK_UNMAPPED_BASE;
 
-	addr = COLOUR_ALIGN(addr);
+	if (flags & MAP_PRIVATE)
+		addr = PAGE_ALIGN(addr);
+	else
+		addr = COLOUR_ALIGN(addr);
 
 	for (vma = find_vma(current->mm, addr); ; vma = vma->vm_next) {
 		/* At this point:  (!vma || addr < vma->vm_end). */
@@ -77,7 +80,8 @@
 		if (!vma || addr + len <= vma->vm_start)
 			return addr;
 		addr = vma->vm_end;
-		addr = COLOUR_ALIGN(addr);
+		if (!(flags & MAP_PRIVATE))
+			addr = COLOUR_ALIGN(addr);
 	}
 }
 #endif
--