64-bit kernel patch.

[Carsten Langgaard <carstenl@mips.com>]

I have a number of patches for the o32 syscall wrapper/conversion
routines, which is needed when running a 64-bit kernel on an o32
userland.
Here is the first one. Ralf, could you please apply it, so I can send
the next one.

/Carsten




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Index: arch/mips64/kernel/linux32.c
===================================================================
RCS file: /home/cvs/linux/arch/mips64/kernel/linux32.c,v
retrieving revision 1.42.2.12
diff -u -r1.42.2.12 linux32.c
--- arch/mips64/kernel/linux32.c	27 Sep 2002 23:29:17 -0000	1.42.2.12
+++ arch/mips64/kernel/linux32.c	2 Oct 2002 13:13:42 -0000
@@ -179,7 +179,32 @@
 	return err;
 }
 
-asmlinkage int sys_mmap2(void) {return 0;}
+asmlinkage unsigned long
+sys32_mmap2(unsigned long addr, size_t len, unsigned long prot,
+         unsigned long flags, unsigned long fd, unsigned long pgoff)
+{
+	struct file * file = NULL;
+	unsigned long error;
+
+	error = -EINVAL;
+	if (!(flags & MAP_ANONYMOUS)) {
+		error = -EBADF;
+		file = fget(fd);
+		if (!file)
+			goto out;
+	}
+	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
+
+	down_write(&current->mm->mmap_sem);
+	error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
+	up_write(&current->mm->mmap_sem);
+	if (file)
+		fput(file);
+
+out:
+	return error;
+}
+
 
 asmlinkage long sys_truncate(const char * path, unsigned long length);
 
Index: arch/mips64/kernel/scall_o32.S
===================================================================
RCS file: /home/cvs/linux/arch/mips64/kernel/scall_o32.S,v
retrieving revision 1.48.2.15
diff -u -r1.48.2.15 scall_o32.S
--- arch/mips64/kernel/scall_o32.S	11 Sep 2002 13:56:36 -0000	1.48.2.15
+++ arch/mips64/kernel/scall_o32.S	2 Oct 2002 13:13:42 -0000
@@ -522,7 +522,7 @@
 	sys	sys_sendfile	4
 	sys	sys_ni_syscall	0
 	sys	sys_ni_syscall	0
-	sys	sys_mmap2	6			/* 4210 */
+	sys	sys32_mmap2	6			/* 4210 */
 	sys	sys_truncate64	2
 	sys	sys_ftruncate64	2
 	sys	sys_newstat	2