[PATCH rfcv1 12/23] intel_iommu: replay pasid binds after context cache invalidation

[Zhenzhong Duan <zhenzhong.duan@intel.com>]

From: Yi Liu <yi.l.liu@intel.com>

This replays guest pasid attachments after context cache
invalidation. This is a behavior to ensure safety. Actually,
programmer should issue pasid cache invalidation with proper
granularity after issuing a context cache invalidation.

Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Signed-off-by: Yi Sun <yi.y.sun@linux.intel.com>
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
---
 hw/i386/intel_iommu_internal.h |  1 +
 hw/i386/intel_iommu.c          | 49 ++++++++++++++++++++++++++++++++++
 hw/i386/trace-events           |  1 +
 3 files changed, 51 insertions(+)

diff --git a/hw/i386/intel_iommu_internal.h b/hw/i386/intel_iommu_internal.h
index e33c9f54b5..65fe07c13b 100644
--- a/hw/i386/intel_iommu_internal.h
+++ b/hw/i386/intel_iommu_internal.h
@@ -532,6 +532,7 @@ typedef enum VTDPCInvType {
     VTD_PASID_CACHE_FORCE_RESET = 0,
     /* pasid cache invalidation rely on guest PASID entry */
     VTD_PASID_CACHE_GLOBAL_INV,
+    VTD_PASID_CACHE_DEVSI,
     VTD_PASID_CACHE_DOMSI,
     VTD_PASID_CACHE_PASIDSI,
 } VTDPCInvType;
diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c
index 8f9a59ae6f..9058be9efd 100644
--- a/hw/i386/intel_iommu.c
+++ b/hw/i386/intel_iommu.c
@@ -74,6 +74,10 @@ static void vtd_address_space_refresh_all(IntelIOMMUState *s);
 static void vtd_address_space_unmap(VTDAddressSpace *as, IOMMUNotifier *n);
 
 static void vtd_pasid_cache_reset(IntelIOMMUState *s);
+static void vtd_pasid_cache_sync(IntelIOMMUState *s,
+                                 VTDPASIDCacheInfo *pc_info);
+static void vtd_pasid_cache_devsi(IntelIOMMUState *s,
+                                  PCIBus *bus, uint16_t devfn);
 
 static void vtd_panic_require_caching_mode(void)
 {
@@ -2102,6 +2106,8 @@ static void vtd_iommu_replay_all(IntelIOMMUState *s)
 
 static void vtd_context_global_invalidate(IntelIOMMUState *s)
 {
+    VTDPASIDCacheInfo pc_info = { .error_happened = false, };
+
     trace_vtd_inv_desc_cc_global();
     /* Protects context cache */
     vtd_iommu_lock(s);
@@ -2119,6 +2125,9 @@ static void vtd_context_global_invalidate(IntelIOMMUState *s)
      * VT-d emulation codes.
      */
     vtd_iommu_replay_all(s);
+
+    pc_info.type = VTD_PASID_CACHE_GLOBAL_INV;
+    vtd_pasid_cache_sync(s, &pc_info);
 }
 
 static bool iommufd_listener_skipped_section(VTDIOASContainer *container,
@@ -2720,6 +2729,21 @@ static void vtd_context_device_invalidate(IntelIOMMUState *s,
              * happened.
              */
             vtd_address_space_sync(vtd_as);
+            /*
+             * Per spec, context flush should also followed with PASID
+             * cache and iotlb flush. Regards to a device selective
+             * context cache invalidation:
+             * if (emaulted_device)
+             *    invalidate pasid cahce and pasid-based iotlb
+             * else if (assigned_device)
+             *    check if the device has been bound to any pasid
+             *    invoke pasid_unbind regards to each bound pasid
+             * Here, we have vtd_pasid_cache_devsi() to invalidate pasid
+             * caches, while for piotlb in QEMU, we don't have it yet, so
+             * no handling. For assigned device, host iommu driver would
+             * flush piotlb when a pasid unbind is pass down to it.
+             */
+             vtd_pasid_cache_devsi(s, vtd_as->bus, devfn);
         }
     }
 }
@@ -3351,6 +3375,12 @@ static gboolean vtd_flush_pasid(gpointer key, gpointer value,
         /* Fall through */
     case VTD_PASID_CACHE_GLOBAL_INV:
         break;
+    case VTD_PASID_CACHE_DEVSI:
+        if (pc_info->bus != bus ||
+            pc_info->devfn != devfn) {
+            return false;
+        }
+        break;
     default:
         error_report("invalid pc_info->type");
         abort();
@@ -3574,6 +3604,11 @@ static void vtd_replay_guest_pasid_bindings(IntelIOMMUState *s,
     case VTD_PASID_CACHE_GLOBAL_INV:
         /* loop all assigned devices */
         break;
+    case VTD_PASID_CACHE_DEVSI:
+        walk_info.bus = pc_info->bus;
+        walk_info.devfn = pc_info->devfn;
+        vtd_replay_pasid_bind_for_dev(s, start, end, &walk_info);
+        return;
     case VTD_PASID_CACHE_FORCE_RESET:
         /* For force reset, no need to go further replay */
         return;
@@ -3666,6 +3701,20 @@ static void vtd_pasid_cache_sync(IntelIOMMUState *s,
     vtd_iommu_unlock(s);
 }
 
+static void vtd_pasid_cache_devsi(IntelIOMMUState *s,
+                                  PCIBus *bus, uint16_t devfn)
+{
+    VTDPASIDCacheInfo pc_info = { .error_happened = false, };
+
+    trace_vtd_pasid_cache_devsi(devfn);
+
+    pc_info.type = VTD_PASID_CACHE_DEVSI;
+    pc_info.bus = bus;
+    pc_info.devfn = devfn;
+
+    vtd_pasid_cache_sync(s, &pc_info);
+}
+
 /* Caller of this function should hold iommu_lock */
 static void vtd_pasid_cache_reset(IntelIOMMUState *s)
 {
diff --git a/hw/i386/trace-events b/hw/i386/trace-events
index 17e7191696..66f7c1ba59 100644
--- a/hw/i386/trace-events
+++ b/hw/i386/trace-events
@@ -28,6 +28,7 @@ vtd_pasid_cache_gsi(void) ""
 vtd_pasid_cache_reset(void) ""
 vtd_pasid_cache_dsi(uint16_t domain) "Domian slective PC invalidation domain 0x%"PRIx16
 vtd_pasid_cache_psi(uint16_t domain, uint32_t pasid) "PASID slective PC invalidation domain 0x%"PRIx16" pasid 0x%"PRIx32
+vtd_pasid_cache_devsi(uint16_t devfn) "Dev selective PC invalidation dev: 0x%"PRIx16
 vtd_re_not_present(uint8_t bus) "Root entry bus %"PRIu8" not present"
 vtd_ce_not_present(uint8_t bus, uint8_t devfn) "Context entry bus %"PRIu8" devfn %"PRIu8" not present"
 vtd_iotlb_page_hit(uint16_t sid, uint64_t addr, uint64_t slpte, uint16_t domain) "IOTLB page hit sid 0x%"PRIx16" iova 0x%"PRIx64" slpte 0x%"PRIx64" domain 0x%"PRIx16
-- 
2.34.1