Re: [PATCH v4 2/3] xen/pci: solve compilation error on ARM with HAS_PCI enabled.

[Stefano Stabellini <sstabellini@kernel.org>]

On Wed, 25 Nov 2020, Rahul Singh wrote:
> If mem-sharing, mem-paging, or log-dirty functionality is not enabled
> for architecture when HAS_PCI is enabled, the compiler will throw an
> error.
> 
> Move code to x86 specific file to fix compilation error.
> 
> Also, modify the code to use likely() in place of unlikley() for each
> condition to make code more optimized.
> 
> No functional change intended.
> 
> Signed-off-by: Rahul Singh <rahul.singh@arm.com>
> ---
> 
> Changes in v4:
> - fixed minor comments
> 
> ---
>  xen/drivers/passthrough/pci.c       |  8 +-------
>  xen/drivers/passthrough/x86/iommu.c | 13 +++++++++++++
>  xen/include/xen/iommu.h             |  2 ++
>  3 files changed, 16 insertions(+), 7 deletions(-)
> 
> diff --git a/xen/drivers/passthrough/pci.c b/xen/drivers/passthrough/pci.c
> index 3c6ab1bcb6..4c21655b7d 100644
> --- a/xen/drivers/passthrough/pci.c
> +++ b/xen/drivers/passthrough/pci.c
> @@ -20,7 +20,6 @@
>  #include <xen/iommu.h>
>  #include <xen/irq.h>
>  #include <xen/param.h>
> -#include <xen/vm_event.h>
>  #include <xen/delay.h>
>  #include <xen/keyhandler.h>
>  #include <xen/event.h>
> @@ -1418,12 +1417,7 @@ static int assign_device(struct domain *d, u16 seg, u8 bus, u8 devfn, u32 flag)
>      if ( !is_iommu_enabled(d) )
>          return 0;
>  
> -    /* Prevent device assign if mem paging or mem sharing have been 
> -     * enabled for this domain */
> -    if ( d != dom_io &&
> -         unlikely(mem_sharing_enabled(d) ||
> -                  vm_event_check_ring(d->vm_event_paging) ||
> -                  p2m_get_hostp2m(d)->global_logdirty) )
> +    if( !arch_iommu_use_permitted(d) )

code style:

  if ( !arch_iommu_use_permitted(d) )