[ARM] 4878/1: Add oabi shim for fstatat64

Ccoreutils and other have started using fstatat64. Thus, we
need a shim for it if we want to support modern oldabi
userlands (such as Debian/arm/lenny) with EABI kernels.

See http://bugs.debian.org/462677

Acked-by: Nicolas Pitre <[e-mail]>
Signed-off-by: Riku Voipio <[e-mail]>
Signed-off-by: Russell King <[e-mail]>

arch/arm/kernel/calls.S

···
 		CALL(sys_mknodat)
 /* 325 */	CALL(sys_fchownat)
 		CALL(sys_futimesat)
-		CALL(sys_fstatat64)
+		CALL(ABI(sys_fstatat64,  sys_oabi_fstatat64))
 		CALL(sys_unlinkat)
 		CALL(sys_renameat)
 /* 330 */	CALL(sys_linkat)

arch/arm/kernel/sys_oabi-compat.c

···
  * sys_stat64:
  * sys_lstat64:
  * sys_fstat64:
+ * sys_fstatat64:
  *
  *   struct stat64 has different sizes and some members are shifted
  *   Compatibility wrappers are needed for them and provided below.
···
 	int error = vfs_fstat(fd, &stat);
 	if (!error)
 		error = cp_oldabi_stat64(&stat, statbuf);
+	return error;
+}
+
+asmlinkage long sys_oabi_fstatat64(int dfd,
+				   char __user *filename,
+				   struct oldabi_stat64  __user *statbuf,
+				   int flag)
+{
+	struct kstat stat;
+	int error = -EINVAL;
+
+	if ((flag & ~AT_SYMLINK_NOFOLLOW) != 0)
+		goto out;
+
+	if (flag & AT_SYMLINK_NOFOLLOW)
+		error = vfs_lstat_fd(dfd, filename, &stat);
+	else
+		error = vfs_stat_fd(dfd, filename, &stat);
+
+	if (!error)
+	error = cp_oldabi_stat64(&stat, statbuf);
+
+out:
 	return error;
 }