[PATCH v2] staging: vc04_services: rework ioctl code path
Greg KH
gregkh at linuxfoundation.org
Tue Nov 15 01:55:20 PST 2016
On Thu, Nov 10, 2016 at 10:15:31PM -0800, Michael Zoran wrote:
> VCHIQ/vc04_services has a userland device interface
> that includes ioctls. The current ioctl implementation
> is a single monolithic function over 1,000+ lines
> that handles 17 different ioctls through a complex
> maze of switch and if statements.
>
> The change reimplements that code path by breaking
> up the code into smaller, easier to maintain functions
> and uses a dispatch table to invoke the correct function.
>
> Testing:
>
> 1. vchiq_test -f 10 and vchiq_test -p 1 were run from a native
> 64-bit OS(debian sid).
>
> 2. vchiq_test -f 10 and vchiq_test -p 1 where run from a 32-bit
> chroot install from the same OS.
>
> Both test cases pass.
>
> This is V2 of this patch. Changes include:
>
> 1. More code has been moved to the dispatch routine.
> The dispatch routine is now responsible for copying the top-level
> data into and out of kernel space by using the data encoded in
> the ioctl command number.
>
> 2. The number of parameters have been reduced for the handling
> functions by giving a different prototype to ioctls that pass
> no arguments.
>
> 3. Macros in linux/compat.h are now used for compatibility data
> structures.
>
> Signed-off-by: Michael Zoran <mzoran at crowfest.net>
> ---
> .../vc04_services/interface/vchiq_arm/vchiq_arm.c | 1733 +++++++++++++-------
> .../interface/vchiq_arm/vchiq_ioctl.h | 96 ++
> 2 files changed, 1200 insertions(+), 629 deletions(-)
This is a rough patch to review, can you break this up into a patch
series that moves each ioctl to a separate function as needed?
thanks,
greg k-h
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