lkml.org 
[lkml]   [2006]   [Jan]   [25]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: CD writing in future Linux (stirring up a hornets' nest) (was: Rationale for RLIMIT_MEMLOCK?)
    On Wed, Jan 25 2006, Jens Axboe wrote:
    > On Wed, Jan 25 2006, Jan Engelhardt wrote:
    > >
    > > >> And if you check the amount of completely unneeded code Linux currently has
    > > >> just to implement e.g. SG_IO in /dev/hd*, it could even _save_ space in the
    > > >> kernel when converting to a clean SCSI based design.
    > > >
    > > >Please point me at that huge amount of code. Hint: there is none.
    > >
    > > I'm getting a grin:
    > >
    > > 15:46 takeshi:../drivers/ide > find . -type f -print0 | xargs -0 grep SG_IO
    > > (no results)
    > >
    > > Looks like it's already non-redundant :)
    >
    > SG_IO turns requests into REQ_BLOCK_PC (or blk_pc_request()) types, so
    > you should probably check for that as well. But it's truly a miniscule
    > amount of code, and if I got off my ass and folded cdrom_newpc_intr()
    > and cdrom_pc_intr() into one (that was the intention), it would be even
    > less.

    BTW, I should point out that the fact that references to REQ_BLOCK_PC
    and blk_pc_request() exists doesn't indicate duplicated code. Each low
    level driver or layer (like SCSI, not the SCSI low level drivers) need
    to transform REQ_BLOCK_PC requests into their command types.

    --
    Jens Axboe

    -
    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to majordomo@vger.kernel.org
    More majordomo info at http://vger.kernel.org/majordomo-info.html
    Please read the FAQ at http://www.tux.org/lkml/

    \
     
     \ /
      Last update: 2006-01-25 15:59    [W:0.035 / U:60.292 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site