fs: add ksys_chdir() helper; remove in-kernel calls to sys_chdir()
Using this helper allows us to avoid the in-kernel calls to the sys_chdir()
syscall. The ksys_ prefix denotes that this function is meant as a drop-in
replacement for the syscall. In particular, it uses the same calling
convention as sys_chdir().
This patch is part of a series which removes in-kernel calls to syscalls.
On this basis, the syscall entry path can be streamlined. For details, see
http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
diff --git a/init/do_mounts_initrd.c b/init/do_mounts_initrd.c
index 7129326..83f396d 100644
--- a/init/do_mounts_initrd.c
+++ b/init/do_mounts_initrd.c
@@ -42,7 +42,7 @@
ksys_dup(0);
ksys_dup(0);
/* move initrd over / and chdir/chroot in initrd root */
- sys_chdir("/root");
+ ksys_chdir("/root");
ksys_mount(".", "/", NULL, MS_MOVE, NULL);
ksys_chroot(".");
sys_setsid();
@@ -61,7 +61,7 @@
/* mount initrd on rootfs' /root */
mount_block_root("/dev/root.old", root_mountflags & ~MS_RDONLY);
sys_mkdir("/old", 0700);
- sys_chdir("/old");
+ ksys_chdir("/old");
/* try loading default modules from initrd */
load_default_modules();
@@ -86,11 +86,11 @@
ksys_chroot("..");
if (new_decode_dev(real_root_dev) == Root_RAM0) {
- sys_chdir("/old");
+ ksys_chdir("/old");
return;
}
- sys_chdir("/");
+ ksys_chdir("/");
ROOT_DEV = new_decode_dev(real_root_dev);
mount_root();