[Xen-devel] [PATCH v4 07/14] x86/iommu: add IOMMU entries for p2m_mmio_direct pages

[Roger Pau Monne <roger.pau@xxxxxxxxxx>]

There's nothing wrong with allowing the domain to perform DMA transfers to
MMIO areas that it already can access from the CPU, and this allows us to
remove the hack in set_identity_p2m_entry for PVH Dom0.

Signed-off-by: Roger Pau Monné <roger.pau@xxxxxxxxxx>
---
 xen/arch/x86/mm/p2m.c     | 9 ---------
 xen/include/asm-x86/p2m.h | 1 +
 2 files changed, 1 insertion(+), 9 deletions(-)

diff --git a/xen/arch/x86/mm/p2m.c b/xen/arch/x86/mm/p2m.c
index 6a45185..7e33ab6 100644
--- a/xen/arch/x86/mm/p2m.c
+++ b/xen/arch/x86/mm/p2m.c
@@ -1053,16 +1053,7 @@ int set_identity_p2m_entry(struct domain *d, unsigned 
long gfn,
         ret = p2m_set_entry(p2m, gfn, _mfn(gfn), PAGE_ORDER_4K,
                             p2m_mmio_direct, p2ma);
     else if ( mfn_x(mfn) == gfn && p2mt == p2m_mmio_direct && a == p2ma )
-    {
         ret = 0;
-        /*
-         * PVH fixme: during Dom0 PVH construction, p2m entries are being set
-         * but iomem regions are not mapped with IOMMU. This makes sure that
-         * RMRRs are correctly mapped with IOMMU.
-         */
-        if ( is_hardware_domain(d) && !iommu_use_hap_pt(d) )
-            ret = iommu_map_page(d, gfn, gfn, IOMMUF_readable|IOMMUF_writable);
-    }
     else
     {
         if ( flag & XEN_DOMCTL_DEV_RDM_RELAXED )
diff --git a/xen/include/asm-x86/p2m.h b/xen/include/asm-x86/p2m.h
index 7035860..b562da3 100644
--- a/xen/include/asm-x86/p2m.h
+++ b/xen/include/asm-x86/p2m.h
@@ -834,6 +834,7 @@ static inline unsigned int p2m_get_iommu_flags(p2m_type_t 
p2mt)
     case p2m_grant_map_rw:
     case p2m_ram_logdirty:
     case p2m_map_foreign:
+    case p2m_mmio_direct:
         flags =  IOMMUF_readable | IOMMUF_writable;
         break;
     case p2m_ram_ro:
-- 
2.9.3 (Apple Git-75)


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