[lkml]   [2007]   [Oct]   [22]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
    SubjectRe: [PATCH 09/10] Change table chaining layout
    On Mon, 22 Oct 2007, Jens Axboe wrote:
    > Change the page member of the scatterlist structure to be an unsigned
    > long, and encode more stuff in the lower bits:
    > - Bits 0 and 1 zero: this is a normal sg entry. Next sg entry is located
    > at sg + 1.
    > - Bit 0 set: this is a chain entry, the next real entry is at ->page_link
    > with the two low bits masked off.
    > - Bit 1 set: this is the final entry in the sg entry. sg_next() will return
    > NULL when passed such an entry.

    Better safe than sorry...

    Is it possible that a chain entry pointer has bit 1 set on architectures
    (e.g. m68k) where the natural alignment of 32-bit quantities is _2_ bytes,
    not 4?



    Geert Uytterhoeven -- There's lots of Linux beyond ia32 --

    In personal conversations with technical people, I call myself a hacker. But
    when I'm talking to journalists I just say "programmer" or something like that.
    -- Linus Torvalds
    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to
    More majordomo info at
    Please read the FAQ at

     \ /
      Last update: 2007-10-22 21:43    [W:0.030 / U:12.432 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site