On Mon, Dec 7, 2015 at 11:38 PM, Tejun Heo <tj@xxxxxxxxxx> wrote:
> Implement kernfs_walk_and_get() which is similar to
> kernfs_find_and_get() but can walk a path instead of just a name.
>
> v2: Use strlcpy() instead of strlen() + memcpy() as suggested by
> David.
>
> Signed-off-by: Tejun Heo <tj@xxxxxxxxxx>
> Acked-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> Cc: David Miller <davem@xxxxxxxxxxxxx>
> ---
> fs/kernfs/dir.c | 46 ++++++++++++++++++++++++++++++++++++++++++++++
> include/linux/kernfs.h | 12 ++++++++++++
> 2 files changed, 58 insertions(+)
>
> diff --git a/fs/kernfs/dir.c b/fs/kernfs/dir.c
> index 91e0045..742bf4a 100644
> --- a/fs/kernfs/dir.c
> +++ b/fs/kernfs/dir.c
> @@ -694,6 +694,29 @@ static struct kernfs_node *kernfs_find_ns(struct kernfs_node *parent,
> return NULL;
> }
>
> +static struct kernfs_node *kernfs_walk_ns(struct kernfs_node *parent,
> + const unsigned char *path,
> + const void *ns)
> +{
> + static char path_buf[PATH_MAX]; /* protected by kernfs_mutex */
This is showing up in bloat-o-meter as increasing kernel size by 4 KiB.
> + size_t len = strlcpy(path_buf, path, PATH_MAX);
The full input string is copied because strsep() replaces the delimiters by
zeroes?
Can this be handled in some other way?
> + char *p = path_buf;
> + char *name;
> +
> + lockdep_assert_held(&kernfs_mutex);
> +
> + if (len >= PATH_MAX)
> + return NULL;
> +
> + while ((name = strsep(&p, "/")) && parent) {
> + if (*name == '\0')
> + continue;
> + parent = kernfs_find_ns(parent, name, ns);
> + }
> +
> + return parent;
> +}
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
--
To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
