lkml.org 
[lkml]   [2006]   [Jan]   [27]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: How to map high memory for block io
    On Fri, Jan 27, 2006 at 01:14:15PM +0100, Pierre Ossman wrote:
    > Russell, would having a "highmem not supported" flag in the host
    > structure be an acceptable solution? mmc_block could then use that to
    > tell the block layer that bounce buffers are needed. As for other,
    > future, users they would have to take care not to give those drivers
    > highmem sg lists.

    The mmc_block layer only tells the block layer what the driver told it.

    > The current buggy code, was modeled after another MMC driver (mmci). So
    > I suspect there might be more occurrences like this. Perhaps an audit
    > should be added as a janitor project?

    I don't see what the problem is. A sg entry is a list of struct page
    pointers, an offset, and a size. As such, it can't describe a transfer
    which crosses a page because such a structure does not imply that one
    struct page follows another struct page.

    --
    Russell King
    Linux kernel 2.6 ARM Linux - http://www.arm.linux.org.uk/
    maintainer of: 2.6 Serial core
    -
    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: 2006-01-27 20:45    [W:0.020 / U:1.000 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site