[PATCH rfcv3 14/21] intel_iommu: Introduce a new pasid cache invalidation type FORCE_RESET

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

FORCE_RESET is different from GLOBAL_INV which updates pasid cache if
underlying pasid entry is still valid, it drops all the pasid caches.

FORCE_RESET isn't a VTD spec defined invalidation type for pasid cache,
only used internally in system level reset.

Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
---
 hw/i386/intel_iommu_internal.h |  2 ++
 hw/i386/intel_iommu.c          | 28 ++++++++++++++++++++++++++++
 hw/i386/trace-events           |  1 +
 3 files changed, 31 insertions(+)

diff --git a/hw/i386/intel_iommu_internal.h b/hw/i386/intel_iommu_internal.h
index 4f6d9e9036..5e5583d94a 100644
--- a/hw/i386/intel_iommu_internal.h
+++ b/hw/i386/intel_iommu_internal.h
@@ -564,6 +564,8 @@ typedef struct VTDRootEntry VTDRootEntry;
 #define VTD_SM_CONTEXT_ENTRY_RSVD_VAL1      0xffffffffffe00000ULL
 
 typedef enum VTDPCInvType {
+    /* Force reset all */
+    VTD_PASID_CACHE_FORCE_RESET = 0,
     /* pasid cache invalidation rely on guest PASID entry */
     VTD_PASID_CACHE_GLOBAL_INV, /* pasid cache global invalidation */
     VTD_PASID_CACHE_DOMSI,      /* pasid cache domain selective invalidation */
diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c
index 8d9076216c..050b0d3ca2 100644
--- a/hw/i386/intel_iommu.c
+++ b/hw/i386/intel_iommu.c
@@ -86,6 +86,8 @@ struct vtd_iotlb_key {
 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_locked(IntelIOMMUState *s);
+
 static void vtd_panic_require_caching_mode(void)
 {
     error_report("We need to set caching-mode=on for intel-iommu to enable "
@@ -390,6 +392,7 @@ static void vtd_reset_caches(IntelIOMMUState *s)
     vtd_iommu_lock(s);
     vtd_reset_iotlb_locked(s);
     vtd_reset_context_cache_locked(s);
+    vtd_pasid_cache_reset_locked(s);
     vtd_iommu_unlock(s);
 }
 
@@ -3186,6 +3189,8 @@ static gboolean vtd_flush_pasid(gpointer key, gpointer value,
     }
 
     switch (pc_info->type) {
+    case VTD_PASID_CACHE_FORCE_RESET:
+        goto remove;
     case VTD_PASID_CACHE_PASIDSI:
         if (pc_info->pasid != pasid) {
             return false;
@@ -3239,6 +3244,26 @@ remove:
     return true;
 }
 
+/* Caller of this function should hold iommu_lock */
+static void vtd_pasid_cache_reset_locked(IntelIOMMUState *s)
+{
+    VTDPASIDCacheInfo pc_info;
+
+    trace_vtd_pasid_cache_reset();
+
+    pc_info.type = VTD_PASID_CACHE_FORCE_RESET;
+
+    /*
+     * Reset pasid cache is a big hammer, so use g_hash_table_foreach_remove
+     * which will free the vtd_as instances. Also, as a big hammer, use
+     * VTD_PASID_CACHE_FORCE_RESET to ensure all the vtd_as instances are
+     * dropped, meanwhile the change will be passed to host if
+     * HostIOMMUDeviceIOMMUFD is available.
+     */
+    g_hash_table_foreach_remove(s->vtd_address_spaces,
+                                vtd_flush_pasid, &pc_info);
+}
+
 static void vtd_sm_pasid_table_walk_one(IntelIOMMUState *s,
                                         dma_addr_t pt_base,
                                         int start,
@@ -3366,6 +3391,9 @@ static void vtd_replay_guest_pasid_bindings(IntelIOMMUState *s,
     case VTD_PASID_CACHE_GLOBAL_INV:
         /* loop all assigned devices */
         break;
+    case VTD_PASID_CACHE_FORCE_RESET:
+        /* For force reset, no need to go further replay */
+        return;
     default:
         error_report("invalid pc_info->type for replay");
         abort();
diff --git a/hw/i386/trace-events b/hw/i386/trace-events
index ae5bbfcdc0..c8a936eb46 100644
--- a/hw/i386/trace-events
+++ b/hw/i386/trace-events
@@ -24,6 +24,7 @@ vtd_inv_qi_head(uint16_t head) "read head %d"
 vtd_inv_qi_tail(uint16_t head) "write tail %d"
 vtd_inv_qi_fetch(void) ""
 vtd_context_cache_reset(void) ""
+vtd_pasid_cache_reset(void) ""
 vtd_pasid_cache_gsi(void) ""
 vtd_pasid_cache_dsi(uint16_t domain) "Domain selective PC invalidation domain 0x%"PRIx16
 vtd_pasid_cache_psi(uint16_t domain, uint32_t pasid) "PASID selective PC invalidation domain 0x%"PRIx16" pasid 0x%"PRIx32
-- 
2.34.1