On Mon, Dec 7, 2015 at 11:38 PM, Tejun Heo [off-list ref] wrote:
quoted hunk ↗ jump to hunk
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 <redacted>
Acked-by: Greg Kroah-Hartman <redacted>
Cc: David Miller <redacted>
---
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?
quoted hunk ↗ jump to hunk
+ 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-Td1EMuHUCqxL1ZNQvxDV9g@public.gmane.org
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