[PATCH] init/do_mounts.c: replace sys_mount() to do_mount()

Namhyung Kim
2010-08-17T12:37:30Z

sys_mount() just copies all (string) arguments from user space to kernel
and calls do_mount(). In this case we have all args in kernel already so
there is no need to call sys_mount(). One thing we should take care is
'data' have to be in a page unless it is NULL. Do it manually.

Signed-off-by: Namhyung Kim <namhyung@gmail.com>
---
init/do_mounts.c | 18 ++++++++++++++++--
1 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/init/do_mounts.c b/init/do_mounts.c
index 02e3ca4..8eabff6 100644
--- a/init/do_mounts.c
+++ b/init/do_mounts.c
@@ -217,7 +217,21 @@ static void __init get_fs_names(char *page)

static int __init do_mount_root(char *name, char *fs, int flags, void *data)
{
- int err = sys_mount(name, "/root", fs, flags, data);
+ int err;
+ unsigned long data_page = 0;
+
+ if (data) {
+ /* data should be in a page */
+ data_page = __get_free_page(GFP_KERNEL);
+ if (!data_page)
+ return -ENOMEM;
+ strlcpy((char *) data_page, data, PAGE_SIZE);
+ }
+
+ err = do_mount(name, "/root", fs, flags, (void *) data_page);
+
+ if (data_page)
+ free_page(data_page);
if (err)
return err;

@@ -417,6 +431,6 @@ void __init prepare_namespace(void)
mount_root();
out:
devtmpfs_mount("dev");
- sys_mount(".", "/", NULL, MS_MOVE, NULL);
+ do_mount(".", "/", NULL, MS_MOVE, NULL);
sys_chroot(".");
}
--
1.7.0.4