Re: UIO: phys_mem_access_prot() miss?

["Johann Baudy" <johaahn@gmail.com>]

Many thanks Hans,

Sorry for late reply. I'm currently using linux-2.6.24-rc8-xlnx (git.xilinx.com)
I will try to rebase and let you know.

Best regards,
Johann

On Tue, May 13, 2008 at 8:51 PM, Hans J. Koch <hjk@linutronix.de> wrote:
> On Tue, May 13, 2008 at 03:55:29PM +0200, Johann Baudy wrote:
>> Hi Hans, Greg,
>>
>> I need some help on UIO driver.
>> I have to add this below workaround (in uio.c) to be able to access
>> phys memory from user space.
>> I'm currently using PPC arch.
>> Am I wrong? or Is it a miss?
>>
>> static int uio_mmap(struct file *filep, struct vm_area_struct *vma)
>> {
>>
>> ...
>>       switch (idev->info->mem[mi].memtype) {
>>               case UIO_MEM_PHYS:
>> +             vma->vm_page_prot = phys_mem_access_prot(filep,
>> +            idev->info->mem[mi].addr >> PAGE_SHIFT,
>> +                                              vma->vm_end - vma->vm_start,
>> +                                              vma->vm_page_prot);
>>                       return uio_mmap_physical(vma);
>>               case UIO_MEM_LOGICAL:
>> ...
>>
>> }
>>
>> FYI: I've copied those lines from mem char driver in mmap_mem().
>
> Hi Johann,
> what kernel are you using? Similar problems were reported before, and
> we've already applied a patch that should fix it. I think it hit
> mainline shortly before the 2.6.25 release. uio_mmap() should work with
> kernels >= 2.6.25 for PPC.
>
> Thanks,
> Hans
>
>



-- 
Johann Baudy
johaahn@gmail.com