[PATCH] fix CONFIG_DEVFS=y root=<number>

[Milton Miller <miltonm@bga.com>]

Based on a patch by Adam J. Richter <adam@yggdrasil.com> [1], this fixes
the problem since 2.5.47 with mounting a devfs=y system with root=<number>

sys_get_dents64 returns -EINVAL if there is not space for an entry, so
we need to activate the loop code to expand the buffer.  

[1] http://marc.theaimsgroup.com/?l=linux-kernel&m=103762980207529&w=2
Tested with 2.5.53-um2


diff -Nru a/init/do_mounts.c b/init/do_mounts.c
--- a/init/do_mounts.c	Sat Jan  4 00:14:34 2003
+++ b/init/do_mounts.c	Sat Jan  4 00:14:34 2003
@@ -333,7 +333,7 @@
 	for (bytes = 0, p = buf; bytes < len; bytes += n, p+=n) {
 		n = sys_getdents64(fd, p, len - bytes);
 		if (n < 0)
-			return -1;
+			return n;
 		if (n == 0)
 			return bytes;
 	}
@@ -361,7 +361,7 @@
 			return p;
 		}
 		kfree(p);
-		if (n < 0)
+		if (n < 0 && n != -EINVAL)
 			break;
 	}
 	close(fd);