Hi Nidhi, Seems like you are stuck up with this issue. Refer the following links if you haven't Check out this link to understand block device driver http://lwn.net/Articles/driver-porting/ for bio structures check this link http://lwn.net/Articles/26404/ > > in gyst : > when you actually transfer data in request processing function > using req->current_nr_sectors > from req->buffer > in while elv_next_request loop Please try to provide with the code snippet, will help us understand the problem better. > and if its transferred successfully book does end_request(req,1) > > then my ques is > Q1. end_request doesnt end the request but ends the part of request > what is that part --- a bio OR a segment or what ? > A request consists of a list of bios and bios consists of several segments, and the end request is called to finish the processing of current request. > by seeing current_nr_sectors it seems it transfer segment by segment --- > but seeing req->buffer (equivalent to bio_data(current bio)) seems transferring bio by bio ?? > i think you are referring to sbd_transfer() function, sbd_transfer(&Device, req->sector, req->current_nr_sectors, req->buffer, rq_data_dir(req)); what i understand is that it says transfer these many sectors 'req->current_nr_sectors' starting from sector no. 'req->sector' from buffer 'req->buffer' and direction of data 'rq_data_dir(req)' --> says READ or WRITE request. I hope that helps. Thanks. > > Nidhi > > > > > > > > > > > > > > > > > > > -- > Thanks & Regards > Nidhi -- To unsubscribe from this list: send an email with "unsubscribe kernelnewbies" to ecartis@xxxxxxxxxxxx Please read the FAQ at http://kernelnewbies.org/FAQ
