sysfs, kernfs: implement kernfs_ns_enabled()
fs/sysfs/symlink.c::sysfs_delete_link() tests @sd->s_flags for
SYSFS_FLAG_NS. Let's add kernfs_ns_enabled() so that sysfs doesn't
have to test sysfs_dirent flag directly. This makes things tidier for
kernfs proper too.
This is purely cosmetic.
v2: To avoid possible NULL deref, use noop dummy implementation which
always returns false when !CONFIG_SYSFS.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/fs/kernfs/dir.c b/fs/kernfs/dir.c
index 7c5b517..f51e062 100644
--- a/fs/kernfs/dir.c
+++ b/fs/kernfs/dir.c
@@ -291,7 +291,7 @@
goto out_bad;
/* The sysfs dirent has been moved to a different namespace */
- if (sd->s_parent && (sd->s_parent->s_flags & SYSFS_FLAG_NS) &&
+ if (sd->s_parent && kernfs_ns_enabled(sd->s_parent) &&
sysfs_info(dentry->d_sb)->ns != sd->s_ns)
goto out_bad;
@@ -414,7 +414,7 @@
int sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd,
struct sysfs_dirent *parent_sd)
{
- bool has_ns = parent_sd->s_flags & SYSFS_FLAG_NS;
+ bool has_ns = kernfs_ns_enabled(parent_sd);
struct sysfs_inode_attrs *ps_iattr;
int ret;
@@ -535,7 +535,7 @@
const void *ns)
{
struct rb_node *node = parent->s_dir.children.rb_node;
- bool has_ns = parent->s_flags & SYSFS_FLAG_NS;
+ bool has_ns = kernfs_ns_enabled(parent);
unsigned int hash;
lockdep_assert_held(&sysfs_mutex);
@@ -685,7 +685,7 @@
mutex_lock(&sysfs_mutex);
- if (parent_sd->s_flags & SYSFS_FLAG_NS)
+ if (kernfs_ns_enabled(parent_sd))
ns = sysfs_info(dir->i_sb)->ns;
sd = kernfs_find_ns(parent_sd, dentry->d_name.name, ns);
@@ -968,7 +968,7 @@
return 0;
mutex_lock(&sysfs_mutex);
- if (parent_sd->s_flags & SYSFS_FLAG_NS)
+ if (kernfs_ns_enabled(parent_sd))
ns = sysfs_info(dentry->d_sb)->ns;
for (pos = sysfs_dir_pos(ns, parent_sd, ctx->pos, pos);