[Qemu-devel] [PATCH v4 15/16] intel_iommu: introduce IEC notifiers

[Peter Xu <peterx@redhat.com>]

This patch introduces Intel VT-d IEC (Interrupt Entry Cache)
invalidation notifier list. When vIOMMU receives IEC invalidate request,
all the registered units will be notified with specific invalidation
requests.

Signed-off-by: Peter Xu <peterx@redhat.com>
---
 hw/i386/intel_iommu.c          | 52 ++++++++++++++++++++++++++++++++++++------
 hw/i386/intel_iommu_internal.h | 24 +++++++++++++++----
 include/hw/i386/intel_iommu.h  | 22 ++++++++++++++++++
 3 files changed, 87 insertions(+), 11 deletions(-)

diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c
index ca7e069..1082ab5 100644
--- a/hw/i386/intel_iommu.c
+++ b/hw/i386/intel_iommu.c
@@ -902,12 +902,18 @@ static void vtd_root_table_setup(IntelIOMMUState *s)
 
 static void vtd_interrupt_remap_table_setup(IntelIOMMUState *s)
 {
+    VTD_IEC_Notifier *notifier;
     uint64_t value = 0;
     value = vtd_get_quad_raw(s, DMAR_IRTA_REG);
     s->intr_size = 1UL << ((value & VTD_IRTA_SIZE_MASK) + 1);
     s->intr_root = value & VTD_IRTA_ADDR_MASK;
 
-    /* TODO: invalidate interrupt entry cache */
+    QLIST_FOREACH(notifier, &s->iec_notifiers, list) {
+        if (notifier->iec_notify) {
+            /* Notify global invalidation */
+            notifier->iec_notify(notifier->private, true, 0, 0);
+        }
+    }
 
     VTD_DPRINTF(CSR, "int remap table addr 0x%"PRIx64 " size %"PRIu32,
                 s->intr_root, s->intr_size);
@@ -1409,6 +1415,28 @@ static bool vtd_process_iotlb_desc(IntelIOMMUState *s, VTDInvDesc *inv_desc)
     return true;
 }
 
+static bool vtd_process_inv_iec_desc(IntelIOMMUState *s,
+                                     VTDInvDesc *inv_desc)
+{
+    VTD_IEC_Notifier *notifier;
+
+    VTD_DPRINTF(INV, "inv ir glob %d index %d mask %d",
+                inv_desc->iec.granularity,
+                inv_desc->iec.index,
+                inv_desc->iec.index_mask);
+
+    QLIST_FOREACH(notifier, &s->iec_notifiers, list) {
+        if (notifier->iec_notify) {
+            notifier->iec_notify(notifier->private,
+                                 inv_desc->iec.granularity,
+                                 inv_desc->iec.index,
+                                 inv_desc->iec.index_mask);
+        }
+    }
+
+    return true;
+}
+
 static bool vtd_process_inv_desc(IntelIOMMUState *s)
 {
     VTDInvDesc inv_desc;
@@ -1449,12 +1477,12 @@ static bool vtd_process_inv_desc(IntelIOMMUState *s)
         break;
 
     case VTD_INV_DESC_IEC:
-        VTD_DPRINTF(INV, "Interrupt Entry Cache Invalidation "
-                    "not implemented yet");
-        /*
-         * Since currently we do not cache interrupt entries, we can
-         * just mark this descriptor as "good" and move on.
-         */
+        VTD_DPRINTF(INV, "Invalidation Interrupt Entry Cache "
+                    "Descriptor hi 0x%"PRIx64 " lo 0x%"PRIx64,
+                    inv_desc.hi, inv_desc.lo);
+        if (!vtd_process_inv_iec_desc(s, &inv_desc)) {
+            return false;
+        }
         break;
 
     default:
@@ -2202,6 +2230,15 @@ static const MemoryRegionOps vtd_mem_ir_ops = {
     },
 };
 
+void vtd_iec_register_notifier(IntelIOMMUState *s, vtd_iec_notify_fn fn,
+                               void *data)
+{
+    VTD_IEC_Notifier *notifier = g_new0(VTD_IEC_Notifier, 1);
+    notifier->iec_notify = fn;
+    notifier->private = data;
+    QLIST_INSERT_HEAD(&s->iec_notifiers, notifier, list);
+}
+
 VTDAddressSpace *vtd_find_add_as(IntelIOMMUState *s, PCIBus *bus, int devfn)
 {
     uintptr_t key = (uintptr_t)bus;
@@ -2364,6 +2401,7 @@ static void vtd_realize(DeviceState *dev, Error **errp)
                                      g_free, g_free);
     s->vtd_as_by_busptr = g_hash_table_new_full(vtd_uint64_hash, vtd_uint64_equal,
                                               g_free, g_free);
+    QLIST_INIT(&s->iec_notifiers);
     vtd_init(s);
 }
 
diff --git a/hw/i386/intel_iommu_internal.h b/hw/i386/intel_iommu_internal.h
index e1a08cb..10c20fe 100644
--- a/hw/i386/intel_iommu_internal.h
+++ b/hw/i386/intel_iommu_internal.h
@@ -296,12 +296,28 @@ typedef enum VTDFaultReason {
 
 #define VTD_CONTEXT_CACHE_GEN_MAX       0xffffffffUL
 
+/* Interrupt Entry Cache Invalidation Descriptor: VT-d 6.5.2.7. */
+struct VTDInvDescIEC {
+    uint32_t type:4;            /* Should always be 0x4 */
+    uint32_t granularity:1;     /* If set, it's global IR invalidation */
+    uint32_t resved_1:22;
+    uint32_t index_mask:5;      /* 2^N for continuous int invalidation */
+    uint32_t index:16;          /* Start index to invalidate */
+    uint32_t reserved_2:16;
+};
+typedef struct VTDInvDescIEC VTDInvDescIEC;
+
 /* Queued Invalidation Descriptor */
-struct VTDInvDesc {
-    uint64_t lo;
-    uint64_t hi;
+union VTDInvDesc {
+    struct {
+        uint64_t lo;
+        uint64_t hi;
+    };
+    union {
+        VTDInvDescIEC iec;
+    };
 };
-typedef struct VTDInvDesc VTDInvDesc;
+typedef union VTDInvDesc VTDInvDesc;
 
 /* Masks for struct VTDInvDesc */
 #define VTD_INV_DESC_TYPE               0xf
diff --git a/include/hw/i386/intel_iommu.h b/include/hw/i386/intel_iommu.h
index 5910e6f..d7613af 100644
--- a/include/hw/i386/intel_iommu.h
+++ b/include/hw/i386/intel_iommu.h
@@ -203,6 +203,24 @@ struct VTD_MSIMessage {
 /* When IR is enabled, all MSI/MSI-X data bits should be zero */
 #define VTD_IR_MSI_DATA          (0)
 
+/**
+ * iec_notifier - IEC (Interrupt Entry Cache) notifier, triggered
+ *                when IR hhinvalidation happens.
+ * @private: private data
+ * @global: whether this is a global IEC invalidation
+ * @index: IRTE index to invalidate (start from)
+ * @mask: invalidation mask
+ */
+typedef void (*vtd_iec_notify_fn)(void *private, bool global,
+                                  uint32_t index, uint32_t mask);
+
+struct VTD_IEC_Notifier {
+    vtd_iec_notify_fn iec_notify;
+    void *private;
+    QLIST_ENTRY(VTD_IEC_Notifier) list;
+};
+typedef struct VTD_IEC_Notifier VTD_IEC_Notifier;
+
 /* The iommu (DMAR) device state struct */
 struct IntelIOMMUState {
     SysBusDevice busdev;
@@ -243,6 +261,7 @@ struct IntelIOMMUState {
     bool intr_enabled;              /* Whether guest enabled IR */
     dma_addr_t intr_root;           /* Interrupt remapping table pointer */
     uint32_t intr_size;             /* Number of IR table entries */
+    QLIST_HEAD(, VTD_IEC_Notifier) iec_notifiers; /* IEC notify list */
 };
 
 /* Find the VTD Address space associated with the given bus pointer,
@@ -252,5 +271,8 @@ VTDAddressSpace *vtd_find_add_as(IntelIOMMUState *s, PCIBus *bus, int devfn);
 /* Get default IOMMU object */
 IntelIOMMUState *vtd_iommu_get(void);
 int vtd_int_remap(void *iommu, MSIMessage *src, MSIMessage *dst);
+/* Register IEC invalidate notifier */
+void vtd_iec_register_notifier(IntelIOMMUState *s, vtd_iec_notify_fn fn,
+                               void *data);
 
 #endif
-- 
2.4.3