pseries: Reset emulated PCI TCE tables on system reset

The emulated PCI host bridge on the pseries machine incorporates an IOMMU
(PAPR TCE table).  Currently the mappings in this IOMMU are not cleared
when we reset the system.  This patch fixes this bug.  To do this it adds
a new reset function to the IOMMU emulation code.  The VIO devices already
reset their TCE tables, but they do so by destroying and re-creating their
DMA context.  This doesn't work for the PCI host bridge, because the
infrastructure for PCI IOMMUs has already copied/cached the DMA pointer
context into the subordinate PCI device structures.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexander Graf <agraf@suse.de>

diff --git a/hw/spapr.h b/hw/spapr.h
index f1fb646a5658a0e0bef91323cefb03f5c4ebe5f1..f9a7b0fa3327408ad913c4e9eb005b575ee97d20 100644 (file)
--- a/hw/spapr.h
+++ b/hw/spapr.h
@@ -338,6 +338,7 @@ typedef struct sPAPRTCE {
 void spapr_iommu_init(void);
 DMAContext *spapr_tce_new_dma_context(uint32_t liobn, size_t window_size);
 void spapr_tce_free(DMAContext *dma);
+void spapr_tce_reset(DMAContext *dma);
 int spapr_dma_dt(void *fdt, int node_off, const char *propname,
                  uint32_t liobn, uint64_t window, uint32_t size);
 int spapr_tcet_dma_dt(void *fdt, int node_off, const char *propname,

diff --git a/hw/spapr_iommu.c b/hw/spapr_iommu.c
index 53b731773abc1f7e6d79fa3acd16a401f48771d7..216aa068090b770059588f1a3c000e5615ef92e8 100644 (file)
--- a/hw/spapr_iommu.c
+++ b/hw/spapr_iommu.c
@@ -162,6 +162,17 @@ void spapr_tce_free(DMAContext *dma)
     }
 }
 
+void spapr_tce_reset(DMAContext *dma)
+{
+    if (dma) {
+        sPAPRTCETable *tcet = DO_UPCAST(sPAPRTCETable, dma, dma);
+        size_t table_size = (tcet->window_size >> SPAPR_TCE_PAGE_SHIFT)
+            * sizeof(sPAPRTCE);
+
+        memset(tcet->table, 0, table_size);
+    }
+}
+
 static target_ulong put_tce_emu(sPAPRTCETable *tcet, target_ulong ioba,
                                 target_ulong tce)
 {

diff --git a/hw/spapr_pci.c b/hw/spapr_pci.c
index 661c05bc308635fa1c4d73ad183d985c8362a673..203155e32b70d02e0ab7b690296caf36e9e3b4ba 100644 (file)
--- a/hw/spapr_pci.c
+++ b/hw/spapr_pci.c
@@ -595,6 +595,15 @@ static int spapr_phb_init(SysBusDevice *s)
     return 0;
 }
 
+static void spapr_phb_reset(DeviceState *qdev)
+{
+    SysBusDevice *s = sysbus_from_qdev(qdev);
+    sPAPRPHBState *sphb = SPAPR_PCI_HOST_BRIDGE(s);
+
+    /* Reset the IOMMU state */
+    spapr_tce_reset(sphb->dma);
+}
+
 static Property spapr_phb_properties[] = {
     DEFINE_PROP_HEX64("buid", sPAPRPHBState, buid, 0),
     DEFINE_PROP_STRING("busname", sPAPRPHBState, busname),
@@ -613,6 +622,7 @@ static void spapr_phb_class_init(ObjectClass *klass, void *data)
 
     sdc->init = spapr_phb_init;
     dc->props = spapr_phb_properties;
+    dc->reset = spapr_phb_reset;
 }
 
 static const TypeInfo spapr_phb_info = {