pluginfs: use only one file instance for hidden file

Signed-off-by: Frantisek Hrbata <fhrbata@redhat.com>
pluginfs: user vfs_read for readpage

Signed-off-by: Frantisek Hrbata <fhrbata@redhat.com>
pluginfs: user vfs_write for writepage

Signed-off-by: Frantisek Hrbata <fhrbata@redhat.com>
pluginfs: add plgfs_read_hidden

Signed-off-by: Frantisek Hrbata <fhrbata@redhat.com>
pluginfs: add plgfs_write_hidden

Signed-off-by: Frantisek Hrbata <fhrbata@redhat.com>
pluginfs: set plg_id for context

Signed-off-by: Frantisek Hrbata <fhrbata@redhat.com>
pluginfs: set corrent page state in readpage

Signed-off-by: Frantisek Hrbata <fhrbata@redhat.com>
pluginfs: set corrent page state in writepage

Signed-off-by: Frantisek Hrbata <fhrbata@redhat.com>
pluginfs: use contex page for read/write page

Signed-off-by: Frantisek Hrbata <fhrbata@redhat.com>
pluginfs: add write_begin and write_end reg aops

Signed-off-by: Frantisek Hrbata <fhrbata@redhat.com>
pluginfs: use kernel_read and kernel_write

Signed-off-by: Frantisek Hrbata <fhrbata@redhat.com>
pluginfs: rename plgfs_(read|write)_hidden to plgfs_(read|write)

Signed-off-by: Frantisek Hrbata <fhrbata@redhat.com>
pluginfs: plgfs_(read|write)page return number of read/write bytes

Signed-off-by: Frantisek Hrbata <fhrbata@redhat.com>