• Tejun Heo's avatar
    sysfs, kernfs: prepare mount path for kernfs · 4b93dc9b
    Tejun Heo authored
    We're in the process of separating out core sysfs functionality into
    kernfs which will deal with sysfs_dirents directly.  This patch
    rearranges mount path so that the kernfs and sysfs parts are separate.
    * As sysfs_super_info won't be visible outside kernfs proper,
      kernfs_super_ns() is added to allow kernfs users to access a
      super_block's namespace tag.
    * Generic mount operation is separated out into kernfs_mount_ns().
      sysfs_mount() now just performs sysfs-specific permission check,
      acquires namespace tag, and invokes kernfs_mount_ns().
    * Generic superblock release is separated out into kernfs_kill_sb()
      which can be used directly as file_system_type->kill_sb().  As sysfs
      needs to put the namespace tag, sysfs_kill_sb() wraps
      kernfs_kill_sb() with ns tag put.
    * sysfs_dir_cachep init and sysfs_inode_init() are separated out into
      kernfs_init().  kernfs_init() uses only small amount of memory and
      trying to handle and propagate kernfs_init() failure doesn't make
      much sense.  Use SLAB_PANIC for sysfs_dir_cachep and make
      sysfs_inode_init() panic on failure.
      After this change, kernfs_init() should be called before
      sysfs_init(), fs/namespace.c::mnt_init() modified accordingly.
    Signed-off-by: default avatarTejun Heo <tj@kernel.org>
    Cc: linux-fsdevel@vger.kernel.org
    Cc: Christoph Hellwig <hch@infradead.org>
    Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
kernfs.h 6.8 KB