Re: [RFC] igb_uio: deprecate iomem and ioport mapping

[Ferruh Yigit <ferruh.yigit@intel.com>]

On 9/1/2016 3:16 AM, Jianfeng Tan wrote:
> Previously in igb_uio, iomem is mapped, and both ioport and io mem
> are recorded into uio framework, which is duplicated and makes the
> code too complex.
> 
> For iomem, DPDK user space code never opens or reads files under
> /sys/pci/bus/devices/xxxx:xx:xx.x/uio/uioY/maps/. Instead,
> /sys/pci/bus/devices/xxxx:xx:xx.x/resourceY are used to map device
> memory.
> 
> For ioport, non-x86 platforms cannot read from files under
> /sys/pci/bus/devices/xxxx:xx:xx.x/uio/uioY/portio/ directly, because
> non-x86 platforms need to map port region for access in user space,
> see non-x86 version pci_uio_ioport_map(). x86 platforms can use the
> the same way as uio_pci_generic.
> 
> This patch deprecates iomem and ioport mapping in igb_uio kernel
> module, and adjusts the iomem implementation in both igb_uio and
> uio_pci_generic:
>   - for x86 platform, get ports info from /proc/ioports;
>   - for non-x86 platform, map and get ports info by pci_uio_ioport_map().
> 
> Note: this will affect those applications who are using files under
> /sys/pci/bus/devices/xxxx:xx:xx.x/uio/uioY/maps/ and
> /sys/pci/bus/devices/xxxx:xx:xx.x/uio/uioY/portio/.
> 
> Signed-off-by: Jianfeng Tan <jianfeng.tan@intel.com>
> ---

I think it is good idea to simplify to code, that piece looks like can
go away.

But since sysfs interface exposed to the world, anybody can be using it,

what about this: for this release keep this patch as RFC and send
another deprecation notice patch?
And apply this patch in the following release (17.02).

Thanks,
ferruh