From 50b2625145f4919c3752c9e974f88a5666cac476 Mon Sep 17 00:00:00 2001 From: Rob Landley Date: Tue, 18 Jun 2013 18:13:06 -0500 Subject: Add pivot_root. --- toys/other/pivot_root.c | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) create mode 100644 toys/other/pivot_root.c (limited to 'toys/other/pivot_root.c') diff --git a/toys/other/pivot_root.c b/toys/other/pivot_root.c new file mode 100644 index 00000000..3e4beacb --- /dev/null +++ b/toys/other/pivot_root.c @@ -0,0 +1,31 @@ +/* pivot_root.c - edit system mount tree + * + * Copyright 2012 Rob Landley + +USE_PIVOT_ROOT(NEWTOY(pivot_root, "<2>2", TOYFLAG_USR|TOYFLAG_BIN)) + +config PIVOT_ROOT + bool "pivot_root" + default y + help + usage: pivot_root OLD NEW + + Swap OLD and NEW filesystems (as if by simultaneous mount --move), and + move all processes with chdir or chroot under OLD into NEW (including + kernel threads) so OLD may be unmounted. + + The directory NEW must exist under OLD. This doesn't work on initramfs, + which can't be moved (about the same way PID 1 can't be killed; see + switch_root instead). +*/ + +#define FOR_pivot_root +#include "toys.h" + +#include + +void pivot_root_main(void) +{ + if (syscall(__NR_pivot_root, toys.optargs[0], toys.optargs[1])) + perror_exit("'%s' -> '%s'", toys.optargs[0], toys.optargs[1]); +} -- cgit v1.2.3