does with_lock lock everything inside the block?

Question

Does with_lock lock all models in the block or just the model itself? For example in the following are all the item models inside with_lock locked or is just the entry model locked?

class Entry < ApplicationRecord
  enum state: [:pending, :posted]
    
  has_many :items, dependent: :destroy
 
  def post!
    with_lock do
      return unless pending?
      items.each { |i| i.post! }
      self.posted!
    end
  end
end