splice_from_pipe_feed — feed available data from a pipe to a file
| int fsfuncsplice_from_pipe_feed ( | struct pipe_inode_info * pipe, | 
| struct splice_desc * sd, | |
| splice_actor * actor ); | 
   This function loops over the pipe and calls actor to do the
   actual moving of a single struct pipe_buffer to the desired
   destination.  It returns when there's no more buffers left in
   the pipe or if the requested number of bytes (sd->total_len)
   have been copied.  It returns a positive number (one) if the
   pipe needs to be filled with more data, zero if the required
   number of bytes have been copied and -errno on error.
   
   This, together with splice_from_pipe_{begin,end,next}, may be
   used to implement the functionality of __splice_from_pipe when
   locking is required around copying the pipe buffers to the
   destination.