[PULL 16/48] intel_iommu: Process PASID-based iotlb invalidation

["Michael S. Tsirkin" <mst@redhat.com>]

From: Zhenzhong Duan <zhenzhong.duan@intel.com>

PASID-based iotlb (piotlb) is used during walking Intel
VT-d stage-1 page table.

This emulates the stage-1 page table iotlb invalidation requested
by a PASID-based IOTLB Invalidate Descriptor (P_IOTLB).

Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Reviewed-by: Clément Mathieu--Drif<clement.mathieu--drif@eviden.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Yi Liu <yi.l.liu@intel.com>
Message-Id: <20241212083757.605022-12-zhenzhong.duan@intel.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
 hw/i386/intel_iommu_internal.h |  3 +++
 hw/i386/intel_iommu.c          | 43 ++++++++++++++++++++++++++++++++++
 2 files changed, 46 insertions(+)

diff --git a/hw/i386/intel_iommu_internal.h b/hw/i386/intel_iommu_internal.h
index 22dd3faf0c..5e4e563e62 100644
--- a/hw/i386/intel_iommu_internal.h
+++ b/hw/i386/intel_iommu_internal.h
@@ -471,6 +471,9 @@ typedef union VTDInvDesc VTDInvDesc;
 #define VTD_INV_DESC_PIOTLB_PSI_IN_PASID  (3ULL << 4)
 #define VTD_INV_DESC_PIOTLB_DID(val)      (((val) >> 16) & VTD_DOMAIN_ID_MASK)
 #define VTD_INV_DESC_PIOTLB_PASID(val)    (((val) >> 32) & 0xfffffULL)
+#define VTD_INV_DESC_PIOTLB_AM(val)       ((val) & 0x3fULL)
+#define VTD_INV_DESC_PIOTLB_IH(val)       (((val) >> 6) & 0x1)
+#define VTD_INV_DESC_PIOTLB_ADDR(val)     ((val) & ~0xfffULL)
 #define VTD_INV_DESC_PIOTLB_RSVD_VAL0     0xfff000000000f1c0ULL
 #define VTD_INV_DESC_PIOTLB_RSVD_VAL1     0xf80ULL
 
diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c
index 95f344eb46..c45a486bf8 100644
--- a/hw/i386/intel_iommu.c
+++ b/hw/i386/intel_iommu.c
@@ -322,6 +322,28 @@ static gboolean vtd_hash_remove_by_page(gpointer key, gpointer value,
     return (entry->gfn & info->mask) == gfn || entry->gfn == gfn_tlb;
 }
 
+static gboolean vtd_hash_remove_by_page_piotlb(gpointer key, gpointer value,
+                                               gpointer user_data)
+{
+    VTDIOTLBEntry *entry = (VTDIOTLBEntry *)value;
+    VTDIOTLBPageInvInfo *info = (VTDIOTLBPageInvInfo *)user_data;
+    uint64_t gfn = (info->addr >> VTD_PAGE_SHIFT_4K) & info->mask;
+    uint64_t gfn_tlb = (info->addr & entry->mask) >> VTD_PAGE_SHIFT_4K;
+
+    /*
+     * According to spec, PASID-based-IOTLB Invalidation in page granularity
+     * doesn't invalidate IOTLB entries caching second-stage (PGTT=010b)
+     * or pass-through (PGTT=100b) mappings. Nested isn't supported yet,
+     * so only need to check first-stage (PGTT=001b) mappings.
+     */
+    if (entry->pgtt != VTD_SM_PASID_ENTRY_FLT) {
+        return false;
+    }
+
+    return entry->domain_id == info->domain_id && entry->pasid == info->pasid &&
+           ((entry->gfn & info->mask) == gfn || entry->gfn == gfn_tlb);
+}
+
 /* Reset all the gen of VTDAddressSpace to zero and set the gen of
  * IntelIOMMUState to 1.  Must be called with IOMMU lock held.
  */
@@ -2937,11 +2959,29 @@ static void vtd_piotlb_pasid_invalidate(IntelIOMMUState *s,
     }
 }
 
+static void vtd_piotlb_page_invalidate(IntelIOMMUState *s, uint16_t domain_id,
+                                       uint32_t pasid, hwaddr addr, uint8_t am)
+{
+    VTDIOTLBPageInvInfo info;
+
+    info.domain_id = domain_id;
+    info.pasid = pasid;
+    info.addr = addr;
+    info.mask = ~((1 << am) - 1);
+
+    vtd_iommu_lock(s);
+    g_hash_table_foreach_remove(s->iotlb,
+                                vtd_hash_remove_by_page_piotlb, &info);
+    vtd_iommu_unlock(s);
+}
+
 static bool vtd_process_piotlb_desc(IntelIOMMUState *s,
                                     VTDInvDesc *inv_desc)
 {
     uint16_t domain_id;
     uint32_t pasid;
+    hwaddr addr;
+    uint8_t am;
     uint64_t mask[4] = {VTD_INV_DESC_PIOTLB_RSVD_VAL0,
                         VTD_INV_DESC_PIOTLB_RSVD_VAL1,
                         VTD_INV_DESC_ALL_ONE, VTD_INV_DESC_ALL_ONE};
@@ -2959,6 +2999,9 @@ static bool vtd_process_piotlb_desc(IntelIOMMUState *s,
         break;
 
     case VTD_INV_DESC_PIOTLB_PSI_IN_PASID:
+        am = VTD_INV_DESC_PIOTLB_AM(inv_desc->val[1]);
+        addr = (hwaddr) VTD_INV_DESC_PIOTLB_ADDR(inv_desc->val[1]);
+        vtd_piotlb_page_invalidate(s, domain_id, pasid, addr, am);
         break;
 
     default:
-- 
MST