On Tue, Jul 24, 2018 at 01:56:54PM +1000, Alexey Kardashevskiy wrote: > > > On 23/07/2018 13:11, David Gibson wrote: > > On Wed, Jun 20, 2018 at 07:10:12PM +1000, Alexey Kardashevskiy wrote: > >> At the moment the PPC64/pseries guest only supports 4K/64K/16M IOMMU > >> pages and POWER8 CPU supports the exact same set of page size so > >> so far things worked fine. > >> > >> However POWER9 supports different set of sizes - 4K/64K/2M/1G and > >> the last two - 2M and 1G - are not even allowed in the paravirt interface > >> (RTAS DDW) so we always end up using 64K IOMMU pages, although we could > >> back guest's 16MB IOMMU pages with 2MB pages on the host. > >> > >> This stores the supported host IOMMU page sizes in VFIOContainer and uses > >> this later when creating a new DMA window. This uses the system page size > >> (64k normally, 2M/16M/1G if hugepages used) as the upper limit of > >> the IOMMU pagesize. > >> > >> This changes the type of @pagesize to uint64_t as this is what > >> memory_region_iommu_get_min_page_size() returns and clz64() takes. > >> > >> There should be no behavioral changes on platforms other than pseries. > >> The guest will keep using the IOMMU page size selected by the PHB pagesize > >> property as this only changes the underlying hardware TCE table > >> granularity. > >> > >> Signed-off-by: Alexey Kardashevskiy <a...@ozlabs.ru> > >> --- > >> Changes: > >> v2: > >> * fixed biggest but smaller page size calculation > >> * limit IOMMU pagesize to the system pagesize > > > > Sorry, this fell of my radar for a bit. > > > > I've now applied it to ppc-for-3.1. > > > Alex might object that as it does not have his "rb" ;)
Well, if he does I'll yank it from my tree. It won't be going
upstream for a while yet.
>
>
> >
> >> ---
> >> include/hw/vfio/vfio-common.h | 1 +
> >> hw/vfio/common.c | 3 +++
> >> hw/vfio/spapr.c | 21 ++++++++++++++++++++-
> >> 3 files changed, 24 insertions(+), 1 deletion(-)
> >>
> >> diff --git a/include/hw/vfio/vfio-common.h b/include/hw/vfio/vfio-common.h
> >> index a903692..c20524d 100644
> >> --- a/include/hw/vfio/vfio-common.h
> >> +++ b/include/hw/vfio/vfio-common.h
> >> @@ -73,6 +73,7 @@ typedef struct VFIOContainer {
> >> unsigned iommu_type;
> >> int error;
> >> bool initialized;
> >> + unsigned long pgsizes;
> >> /*
> >> * This assumes the host IOMMU can support only a single
> >> * contiguous IOVA window. We may need to generalize that in
> >> diff --git a/hw/vfio/common.c b/hw/vfio/common.c
> >> index fb396cf..40f0356 100644
> >> --- a/hw/vfio/common.c
> >> +++ b/hw/vfio/common.c
> >> @@ -1108,6 +1108,7 @@ static int vfio_connect_container(VFIOGroup *group,
> >> AddressSpace *as,
> >> info.iova_pgsizes = 4096;
> >> }
> >> vfio_host_win_add(container, 0, (hwaddr)-1, info.iova_pgsizes);
> >> + container->pgsizes = info.iova_pgsizes;
> >> } else if (ioctl(fd, VFIO_CHECK_EXTENSION, VFIO_SPAPR_TCE_IOMMU) ||
> >> ioctl(fd, VFIO_CHECK_EXTENSION, VFIO_SPAPR_TCE_v2_IOMMU)) {
> >> struct vfio_iommu_spapr_tce_info info;
> >> @@ -1172,6 +1173,7 @@ static int vfio_connect_container(VFIOGroup *group,
> >> AddressSpace *as,
> >> }
> >>
> >> if (v2) {
> >> + container->pgsizes = info.ddw.pgsizes;
> >> /*
> >> * There is a default window in just created container.
> >> * To make region_add/del simpler, we better remove this
> >> @@ -1186,6 +1188,7 @@ static int vfio_connect_container(VFIOGroup *group,
> >> AddressSpace *as,
> >> }
> >> } else {
> >> /* The default table uses 4K pages */
> >> + container->pgsizes = 0x1000;
> >> vfio_host_win_add(container, info.dma32_window_start,
> >> info.dma32_window_start +
> >> info.dma32_window_size - 1,
> >> diff --git a/hw/vfio/spapr.c b/hw/vfio/spapr.c
> >> index 259397c..becf71a 100644
> >> --- a/hw/vfio/spapr.c
> >> +++ b/hw/vfio/spapr.c
> >> @@ -15,6 +15,7 @@
> >>
> >> #include "hw/vfio/vfio-common.h"
> >> #include "hw/hw.h"
> >> +#include "exec/ram_addr.h"
> >> #include "qemu/error-report.h"
> >> #include "trace.h"
> >>
> >> @@ -144,9 +145,27 @@ int vfio_spapr_create_window(VFIOContainer *container,
> >> {
> >> int ret;
> >> IOMMUMemoryRegion *iommu_mr = IOMMU_MEMORY_REGION(section->mr);
> >> - unsigned pagesize = memory_region_iommu_get_min_page_size(iommu_mr);
> >> + uint64_t pagesize = memory_region_iommu_get_min_page_size(iommu_mr);
> >> unsigned entries, pages;
> >> struct vfio_iommu_spapr_tce_create create = { .argsz = sizeof(create)
> >> };
> >> + long systempagesize = qemu_getrampagesize();
> >> +
> >> + /*
> >> + * The host might not support the guest supported IOMMU page size,
> >> + * so we will use smaller physical IOMMU pages to back them.
> >> + */
> >> + if (pagesize > systempagesize) {
> >> + pagesize = systempagesize;
> >> + }
> >> + pagesize = 1ULL << (63 - clz64(container->pgsizes &
> >> + (pagesize | (pagesize - 1))));
> >> + if (!pagesize) {
> >> + error_report("Host doesn't support page size 0x%"PRIx64
> >> + ", the supported mask is 0x%lx",
> >> + memory_region_iommu_get_min_page_size(iommu_mr),
> >> + container->pgsizes);
> >> + return -EINVAL;
> >> + }
> >>
> >> /*
> >> * FIXME: For VFIO iommu types which have KVM acceleration to
> >
>
--
David Gibson | I'll have my music baroque, and my code
david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_
| _way_ _around_!
http://www.ozlabs.org/~dgibson
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