kernfs: remove kernfs_addrm_cxt

kernfs_addrm_cxt and the accompanying kernfs_addrm_start/finish() were
added because there were operations which should be performed outside
kernfs_mutex after adding and removing kernfs_nodes.  The necessary
operations were recorded in kernfs_addrm_cxt and performed by
kernfs_addrm_finish(); however, after the recent changes which
relocated deactivation and unmapping so that they're performed
directly during removal, the only operation kernfs_addrm_finish()
performs is kernfs_put(), which can be moved inside the removal path
too.

This patch moves the kernfs_put() of the base ref to __kernfs_remove()
and remove kernfs_addrm_cxt and kernfs_addrm_start/finish().

* kernfs_add_one() is updated to grab and release kernfs_mutex itself.
  sysfs_addrm_start/finish() invocations around it are removed from
  all users.

* __kernfs_remove() puts an unlinked node directly instead of chaining
  it to kernfs_addrm_cxt.  Its callers are updated to grab and release
  kernfs_mutex instead of calling kernfs_addrm_start/finish() around
  it.

v2: Rebased on top of "kernfs: associate a new kernfs_node with its
    parent on creation" which dropped @parent from kernfs_add_one().

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 1 insertions, 5 deletions

diff --git a/fs/kernfs/file.c b/fs/kernfs/file.c
index dbf397bfdff2..10a8c91c49d6 100644
--- a/fs/kernfs/file.c
+++ b/fs/kernfs/file.c
@@ -820,7 +820,6 @@ struct kernfs_node *__kernfs_create_file(struct kernfs_node *parent,
                                          bool name_is_static,
                                          struct lock_class_key *key)
 {
-        struct kernfs_addrm_cxt acxt;
         struct kernfs_node *kn;
         unsigned flags;
         int rc;
@@ -855,10 +854,7 @@ struct kernfs_node *__kernfs_create_file(struct kernfs_node *parent,
         if (ops->mmap)
                 kn->flags |= KERNFS_HAS_MMAP;
 
-        kernfs_addrm_start(&acxt);
-        rc = kernfs_add_one(&acxt, kn);
-        kernfs_addrm_finish(&acxt);
-
+        rc = kernfs_add_one(kn);
         if (rc) {
                 kernfs_put(kn);
                 return ERR_PTR(rc);