Re: udev and devfs - The final word

From: Nathan Conrad (lk_at_bungled.net)
Date: 12/31/03

  • Next message: Marcel Sebek: "Re: IA32 (2.6.0 - 2003-12-29.22.30) - 5 New warnings (gcc 3.2.2)"
    Date:	Wed, 31 Dec 2003 17:01:07 -0500
    To: Rob Love <rml@ximian.com>
    
    

    One thing that I'm confused about with respect to device files is how
    kernel arguments are supposed to work. Now, we _seem_ to have a
    mish-mash of different ways to tell the kernel which device to open as
    a console, which device to use as a suspend device, etc.... Now, all
    of the device names are being migrated to userland. How is the kernel
    supposed to determine which device to use when it is told use
    /dev/hda3 or /dev/ide/host0/something/part3 as the suspend partition?
    The kernel no longer knows to which device this string this device is
    connected.

    (I have not looked into how these parameters are parsed; this is pure
    speculation)

    One solution that I see if the device names are totally removed from
    the kernel is specifying these parameters as sysfs paths. Would this
    work? Or is there a better way?

    -Nathan

    On Wed, Dec 31, 2003 at 03:19:22PM -0500, Rob Love wrote:
    > On Wed, 2003-12-31 at 14:23, Greg KH wrote:
    >
    > > What benefit would there be in "random" numbers? More compressed number
    > > space by giving out numbers sequentially?
    >
    > That is one advantage.
    >
    > > Or less having to work with the numbers because they become just
    > > cookies and never need to be inspected except in very small parts of
    > > the kernel?
    >
    > Yup, especially this one. It is not so much "let's make the device
    > numbers random" but "let's just not care what they are."
    >
    > We can get to the point where we don't even need the explicit concept of
    > device numbers, but just "any old unique value" to use as a cookie. The
    > kernel can pull that number from anywhere, and notify user-space via
    > udev ala hotplug.
    >
    > Rob Love
    >
    >
    > -
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    -- 
    Nathan J. Conrad                     Campus phone #5930
    301 Scott hall, UNC Charlotte        http://bungled.net
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  • Next message: Marcel Sebek: "Re: IA32 (2.6.0 - 2003-12-29.22.30) - 5 New warnings (gcc 3.2.2)"

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