1 files changed, 99 insertions, 1 deletions
diff --git a/hw/ppc/spapr_pci_vfio.c b/hw/ppc/spapr_pci_vfio.c
index 9016720547..f283f7e38d 100644
--- a/hw/ppc/spapr_pci_vfio.c
+++ b/hw/ppc/spapr_pci_vfio.c
@@ -18,14 +18,112 @@
  */
 
 #include "qemu/osdep.h"
+#include <sys/ioctl.h>
 #include <linux/vfio.h>
 #include "hw/ppc/spapr.h"
 #include "hw/pci-host/spapr.h"
 #include "hw/pci/msix.h"
 #include "hw/pci/pci_device.h"
-#include "hw/vfio/vfio.h"
+#include "hw/vfio/vfio-common.h"
 #include "qemu/error-report.h"
 
+/*
+ * Interfaces for IBM EEH (Enhanced Error Handling)
+ */
+static bool vfio_eeh_container_ok(VFIOContainer *container)
+{
+    /*
+     * As of 2016-03-04 (linux-4.5) the host kernel EEH/VFIO
+     * implementation is broken if there are multiple groups in a
+     * container.  The hardware works in units of Partitionable
+     * Endpoints (== IOMMU groups) and the EEH operations naively
+     * iterate across all groups in the container, without any logic
+     * to make sure the groups have their state synchronized.  For
+     * certain operations (ENABLE) that might be ok, until an error
+     * occurs, but for others (GET_STATE) it's clearly broken.
+     */
+
+    /*
+     * XXX Once fixed kernels exist, test for them here
+     */
+
+    if (QLIST_EMPTY(&container->group_list)) {
+        return false;
+    }
+
+    if (QLIST_NEXT(QLIST_FIRST(&container->group_list), container_next)) {
+        return false;
+    }
+
+    return true;
+}
+
+static int vfio_eeh_container_op(VFIOContainer *container, uint32_t op)
+{
+    struct vfio_eeh_pe_op pe_op = {
+        .argsz = sizeof(pe_op),
+        .op = op,
+    };
+    int ret;
+
+    if (!vfio_eeh_container_ok(container)) {
+        error_report("vfio/eeh: EEH_PE_OP 0x%x: "
+                     "kernel requires a container with exactly one group", op);
+        return -EPERM;
+    }
+
+    ret = ioctl(container->fd, VFIO_EEH_PE_OP, &pe_op);
+    if (ret < 0) {
+        error_report("vfio/eeh: EEH_PE_OP 0x%x failed: %m", op);
+        return -errno;
+    }
+
+    return ret;
+}
+
+static VFIOContainer *vfio_eeh_as_container(AddressSpace *as)
+{
+    VFIOAddressSpace *space = vfio_get_address_space(as);
+    VFIOContainer *container = NULL;
+
+    if (QLIST_EMPTY(&space->containers)) {
+        /* No containers to act on */
+        goto out;
+    }
+
+    container = QLIST_FIRST(&space->containers);
+
+    if (QLIST_NEXT(container, next)) {
+        /*
+         * We don't yet have logic to synchronize EEH state across
+         * multiple containers
+         */
+        container = NULL;
+        goto out;
+    }
+
+out:
+    vfio_put_address_space(space);
+    return container;
+}
+
+static bool vfio_eeh_as_ok(AddressSpace *as)
+{
+    VFIOContainer *container = vfio_eeh_as_container(as);
+
+    return (container != NULL) && vfio_eeh_container_ok(container);
+}
+
+static int vfio_eeh_as_op(AddressSpace *as, uint32_t op)
+{
+    VFIOContainer *container = vfio_eeh_as_container(as);
+
+    if (!container) {
+        return -ENODEV;
+    }
+    return vfio_eeh_container_op(container, op);
+}
+
 bool spapr_phb_eeh_available(SpaprPhbState *sphb)
 {
     return vfio_eeh_as_ok(&sphb->iommu_as);