On Thu, 2013-08-22 at 21:29 +1000, Alexey Kardashevskiy wrote:
> Upcoming VFIO on SPAPR PPC64 support will initialize the IOMMU
> memory region with UINT64_MAX (2^64 bytes) size so int128_get64()
> will assert.
>
> The patch takes care of this check. The existing type1 IOMMU code
> is not expected to map all 64 bits of RAM so the patch does not
> touch that part.
>
> Signed-off-by: Alexey Kardashevskiy <a...@ozlabs.ru>
> ---
> Changes:
> v2:
> * used new function int128_exts64()
> ---
> hw/misc/vfio.c | 11 ++++++++---
> 1 file changed, 8 insertions(+), 3 deletions(-)
>
> diff --git a/hw/misc/vfio.c b/hw/misc/vfio.c
> index dfe3a80..3878fc7 100644
> --- a/hw/misc/vfio.c
> +++ b/hw/misc/vfio.c
> @@ -1920,6 +1920,7 @@ static void vfio_listener_region_add(MemoryListener
> *listener,
> VFIOContainer *container = container_of(listener, VFIOContainer,
> iommu_data.listener);
> hwaddr iova, end;
> + Int128 llend;
> void *vaddr;
> int ret;
>
> @@ -1940,13 +1941,17 @@ static void vfio_listener_region_add(MemoryListener
> *listener,
> }
>
> iova = TARGET_PAGE_ALIGN(section->offset_within_address_space);
> - end = (section->offset_within_address_space +
> int128_get64(section->size)) &
> - TARGET_PAGE_MASK;
> + llend = int128_make64(section->offset_within_address_space);
> + llend = int128_add(llend, section->size);
> + llend = int128_and(llend, int128_exts64(TARGET_PAGE_MASK));
>
> - if (iova >= end) {
> + if (int128_ge(int128_make64(iova), llend)) {
> return;
> }
>
> + end = (section->offset_within_address_space +
> int128_get64(section->size)) &
> + TARGET_PAGE_MASK;
> +
I'm confused, we build an Int128 version of end above for the
comparison, why isn't this just:
end = int128_get64(llend);
here? Thanks,
Alex
> vaddr = memory_region_get_ram_ptr(section->mr) +
> section->offset_within_region +
> (iova - section->offset_within_address_space);
