memory: Add IOMMUTLBEvent

This way we can tell between regular IOMMUTLBEntry (entry of IOMMU
hardware) and notifications.

In the notifications, we set explicitly if it is a MAPs or an UNMAP,
instead of trusting in entry permissions to differentiate them.

Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20201116165506.31315-3-eperezma@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Acked-by: David Gibson <david@gibson.dropbear.id.au>

1 files changed, 49 insertions, 39 deletions

diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c
index 067593b9e4..56180b1c43 100644
--- a/hw/i386/intel_iommu.c
+++ b/hw/i386/intel_iommu.c
@@ -1073,7 +1073,7 @@ static int vtd_iova_to_slpte(IntelIOMMUState *s, VTDContextEntry *ce,
     }
 }
 
-typedef int (*vtd_page_walk_hook)(IOMMUTLBEntry *entry, void *private);
+typedef int (*vtd_page_walk_hook)(IOMMUTLBEvent *event, void *private);
 
 /**
  * Constant information used during page walking
@@ -1094,11 +1094,12 @@ typedef struct {
     uint16_t domain_id;
 } vtd_page_walk_info;
 
-static int vtd_page_walk_one(IOMMUTLBEntry *entry, vtd_page_walk_info *info)
+static int vtd_page_walk_one(IOMMUTLBEvent *event, vtd_page_walk_info *info)
 {
     VTDAddressSpace *as = info->as;
     vtd_page_walk_hook hook_fn = info->hook_fn;
     void *private = info->private;
+    IOMMUTLBEntry *entry = &event->entry;
     DMAMap target = {
         .iova = entry->iova,
         .size = entry->addr_mask,
@@ -1107,7 +1108,7 @@ static int vtd_page_walk_one(IOMMUTLBEntry *entry, vtd_page_walk_info *info)
     };
     DMAMap *mapped = iova_tree_find(as->iova_tree, &target);
 
-    if (entry->perm == IOMMU_NONE && !info->notify_unmap) {
+    if (event->type == IOMMU_NOTIFIER_UNMAP && !info->notify_unmap) {
         trace_vtd_page_walk_one_skip_unmap(entry->iova, entry->addr_mask);
         return 0;
     }
@@ -1115,7 +1116,7 @@ static int vtd_page_walk_one(IOMMUTLBEntry *entry, vtd_page_walk_info *info)
     assert(hook_fn);
 
     /* Update local IOVA mapped ranges */
-    if (entry->perm) {
+    if (event->type == IOMMU_NOTIFIER_MAP) {
         if (mapped) {
             /* If it's exactly the same translation, skip */
             if (!memcmp(mapped, &target, sizeof(target))) {
@@ -1141,19 +1142,21 @@ static int vtd_page_walk_one(IOMMUTLBEntry *entry, vtd_page_walk_info *info)
                 int ret;
 
                 /* Emulate an UNMAP */
+                event->type = IOMMU_NOTIFIER_UNMAP;
                 entry->perm = IOMMU_NONE;
                 trace_vtd_page_walk_one(info->domain_id,
                                         entry->iova,
                                         entry->translated_addr,
                                         entry->addr_mask,
                                         entry->perm);
-                ret = hook_fn(entry, private);
+                ret = hook_fn(event, private);
                 if (ret) {
                     return ret;
                 }
                 /* Drop any existing mapping */
                 iova_tree_remove(as->iova_tree, &target);
-                /* Recover the correct permission */
+                /* Recover the correct type */
+                event->type = IOMMU_NOTIFIER_MAP;
                 entry->perm = cache_perm;
             }
         }
@@ -1170,7 +1173,7 @@ static int vtd_page_walk_one(IOMMUTLBEntry *entry, vtd_page_walk_info *info)
     trace_vtd_page_walk_one(info->domain_id, entry->iova,
                             entry->translated_addr, entry->addr_mask,
                             entry->perm);
-    return hook_fn(entry, private);
+    return hook_fn(event, private);
 }
 
 /**
@@ -1191,7 +1194,7 @@ static int vtd_page_walk_level(dma_addr_t addr, uint64_t start,
     uint32_t offset;
     uint64_t slpte;
     uint64_t subpage_size, subpage_mask;
-    IOMMUTLBEntry entry;
+    IOMMUTLBEvent event;
     uint64_t iova = start;
     uint64_t iova_next;
     int ret = 0;
@@ -1245,13 +1248,15 @@ static int vtd_page_walk_level(dma_addr_t addr, uint64_t start,
              *
              * In either case, we send an IOTLB notification down.
              */
-            entry.target_as = &address_space_memory;
-            entry.iova = iova & subpage_mask;
-            entry.perm = IOMMU_ACCESS_FLAG(read_cur, write_cur);
-            entry.addr_mask = ~subpage_mask;
+            event.entry.target_as = &address_space_memory;
+            event.entry.iova = iova & subpage_mask;
+            event.entry.perm = IOMMU_ACCESS_FLAG(read_cur, write_cur);
+            event.entry.addr_mask = ~subpage_mask;
             /* NOTE: this is only meaningful if entry_valid == true */
-            entry.translated_addr = vtd_get_slpte_addr(slpte, info->aw);
-            ret = vtd_page_walk_one(&entry, info);
+            event.entry.translated_addr = vtd_get_slpte_addr(slpte, info->aw);
+            event.type = event.entry.perm ? IOMMU_NOTIFIER_MAP :
+                                            IOMMU_NOTIFIER_UNMAP;
+            ret = vtd_page_walk_one(&event, info);
         }
 
         if (ret < 0) {
@@ -1430,10 +1435,10 @@ static int vtd_dev_to_context_entry(IntelIOMMUState *s, uint8_t bus_num,
     return 0;
 }
 
-static int vtd_sync_shadow_page_hook(IOMMUTLBEntry *entry,
+static int vtd_sync_shadow_page_hook(IOMMUTLBEvent *event,
                                      void *private)
 {
-    memory_region_notify_iommu((IOMMUMemoryRegion *)private, 0, *entry);
+    memory_region_notify_iommu(private, 0, *event);
     return 0;
 }
 
@@ -1993,14 +1998,17 @@ static void vtd_iotlb_page_invalidate_notify(IntelIOMMUState *s,
                  * page tables.  We just deliver the PSI down to
                  * invalidate caches.
                  */
-                IOMMUTLBEntry entry = {
-                    .target_as = &address_space_memory,
-                    .iova = addr,
-                    .translated_addr = 0,
-                    .addr_mask = size - 1,
-                    .perm = IOMMU_NONE,
+                IOMMUTLBEvent event = {
+                    .type = IOMMU_NOTIFIER_UNMAP,
+                    .entry = {
+                        .target_as = &address_space_memory,
+                        .iova = addr,
+                        .translated_addr = 0,
+                        .addr_mask = size - 1,
+                        .perm = IOMMU_NONE,
+                    },
                 };
-                memory_region_notify_iommu(&vtd_as->iommu, 0, entry);
+                memory_region_notify_iommu(&vtd_as->iommu, 0, event);
             }
         }
     }
@@ -2412,7 +2420,7 @@ static bool vtd_process_device_iotlb_desc(IntelIOMMUState *s,
                                           VTDInvDesc *inv_desc)
 {
     VTDAddressSpace *vtd_dev_as;
-    IOMMUTLBEntry entry;
+    IOMMUTLBEvent event;
     struct VTDBus *vtd_bus;
     hwaddr addr;
     uint64_t sz;
@@ -2460,12 +2468,13 @@ static bool vtd_process_device_iotlb_desc(IntelIOMMUState *s,
         sz = VTD_PAGE_SIZE;
     }
 
-    entry.target_as = &vtd_dev_as->as;
-    entry.addr_mask = sz - 1;
-    entry.iova = addr;
-    entry.perm = IOMMU_NONE;
-    entry.translated_addr = 0;
-    memory_region_notify_iommu(&vtd_dev_as->iommu, 0, entry);
+    event.type = IOMMU_NOTIFIER_UNMAP;
+    event.entry.target_as = &vtd_dev_as->as;
+    event.entry.addr_mask = sz - 1;
+    event.entry.iova = addr;
+    event.entry.perm = IOMMU_NONE;
+    event.entry.translated_addr = 0;
+    memory_region_notify_iommu(&vtd_dev_as->iommu, 0, event);
 
 done:
     return true;
@@ -3485,19 +3494,20 @@ static void vtd_address_space_unmap(VTDAddressSpace *as, IOMMUNotifier *n)
     size = remain = end - start + 1;
 
     while (remain >= VTD_PAGE_SIZE) {
-        IOMMUTLBEntry entry;
+        IOMMUTLBEvent event;
         uint64_t mask = get_naturally_aligned_size(start, remain, s->aw_bits);
 
         assert(mask);
 
-        entry.iova = start;
-        entry.addr_mask = mask - 1;
-        entry.target_as = &address_space_memory;
-        entry.perm = IOMMU_NONE;
+        event.type = IOMMU_NOTIFIER_UNMAP;
+        event.entry.iova = start;
+        event.entry.addr_mask = mask - 1;
+        event.entry.target_as = &address_space_memory;
+        event.entry.perm = IOMMU_NONE;
         /* This field is meaningless for unmap */
-        entry.translated_addr = 0;
+        event.entry.translated_addr = 0;
 
-        memory_region_notify_iommu_one(n, &entry);
+        memory_region_notify_iommu_one(n, &event);
 
         start += mask;
         remain -= mask;
@@ -3533,9 +3543,9 @@ static void vtd_address_space_refresh_all(IntelIOMMUState *s)
     vtd_switch_address_space_all(s);
 }
 
-static int vtd_replay_hook(IOMMUTLBEntry *entry, void *private)
+static int vtd_replay_hook(IOMMUTLBEvent *event, void *private)
 {
-    memory_region_notify_iommu_one((IOMMUNotifier *)private, entry);
+    memory_region_notify_iommu_one(private, event);
     return 0;
 }