vfio: Add migration region initialization and finalize function

Whether the VFIO device supports migration or not is decided based of
migration region query. If migration region query is successful and migration
region initialization is successful then migration is supported else
migration is blocked.

Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Reviewed-by: Neo Jia <cjia@nvidia.com>
Acked-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

diff --git a/hw/vfio/meson.build b/hw/vfio/meson.build
index 37efa74018bc0800d0cf78c5f92446bc09f91384..da9af297a0c5914e39be0a6f515caddd37542471 100644 (file)
--- a/hw/vfio/meson.build
+++ b/hw/vfio/meson.build
@@ -2,6 +2,7 @@ vfio_ss = ss.source_set()
 vfio_ss.add(files(
   'common.c',
   'spapr.c',
+  'migration.c',
 ))
 vfio_ss.add(when: 'CONFIG_VFIO_PCI', if_true: files(
   'display.c',

diff --git a/hw/vfio/migration.c b/hw/vfio/migration.c
new file mode 100644 (file)
index 0000000..fd7faf4
--- /dev/null
+++ b/hw/vfio/migration.c
@@ -0,0 +1,122 @@
+/*
+ * Migration support for VFIO devices
+ *
+ * Copyright NVIDIA, Inc. 2020
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2. See
+ * the COPYING file in the top-level directory.
+ */
+
+#include "qemu/osdep.h"
+#include <linux/vfio.h>
+
+#include "hw/vfio/vfio-common.h"
+#include "cpu.h"
+#include "migration/migration.h"
+#include "migration/qemu-file.h"
+#include "migration/register.h"
+#include "migration/blocker.h"
+#include "migration/misc.h"
+#include "qapi/error.h"
+#include "exec/ramlist.h"
+#include "exec/ram_addr.h"
+#include "pci.h"
+#include "trace.h"
+
+static void vfio_migration_exit(VFIODevice *vbasedev)
+{
+    VFIOMigration *migration = vbasedev->migration;
+
+    vfio_region_exit(&migration->region);
+    vfio_region_finalize(&migration->region);
+    g_free(vbasedev->migration);
+    vbasedev->migration = NULL;
+}
+
+static int vfio_migration_init(VFIODevice *vbasedev,
+                               struct vfio_region_info *info)
+{
+    int ret;
+    Object *obj;
+
+    if (!vbasedev->ops->vfio_get_object) {
+        return -EINVAL;
+    }
+
+    obj = vbasedev->ops->vfio_get_object(vbasedev);
+    if (!obj) {
+        return -EINVAL;
+    }
+
+    vbasedev->migration = g_new0(VFIOMigration, 1);
+
+    ret = vfio_region_setup(obj, vbasedev, &vbasedev->migration->region,
+                            info->index, "migration");
+    if (ret) {
+        error_report("%s: Failed to setup VFIO migration region %d: %s",
+                     vbasedev->name, info->index, strerror(-ret));
+        goto err;
+    }
+
+    if (!vbasedev->migration->region.size) {
+        error_report("%s: Invalid zero-sized VFIO migration region %d",
+                     vbasedev->name, info->index);
+        ret = -EINVAL;
+        goto err;
+    }
+    return 0;
+
+err:
+    vfio_migration_exit(vbasedev);
+    return ret;
+}
+
+/* ---------------------------------------------------------------------- */
+
+int vfio_migration_probe(VFIODevice *vbasedev, Error **errp)
+{
+    struct vfio_region_info *info = NULL;
+    Error *local_err = NULL;
+    int ret;
+
+    ret = vfio_get_dev_region_info(vbasedev, VFIO_REGION_TYPE_MIGRATION,
+                                   VFIO_REGION_SUBTYPE_MIGRATION, &info);
+    if (ret) {
+        goto add_blocker;
+    }
+
+    ret = vfio_migration_init(vbasedev, info);
+    if (ret) {
+        goto add_blocker;
+    }
+
+    g_free(info);
+    trace_vfio_migration_probe(vbasedev->name, info->index);
+    return 0;
+
+add_blocker:
+    error_setg(&vbasedev->migration_blocker,
+               "VFIO device doesn't support migration");
+    g_free(info);
+
+    ret = migrate_add_blocker(vbasedev->migration_blocker, &local_err);
+    if (local_err) {
+        error_propagate(errp, local_err);
+        error_free(vbasedev->migration_blocker);
+        vbasedev->migration_blocker = NULL;
+    }
+    return ret;
+}
+
+void vfio_migration_finalize(VFIODevice *vbasedev)
+{
+    if (vbasedev->migration) {
+        vfio_migration_exit(vbasedev);
+    }
+
+    if (vbasedev->migration_blocker) {
+        migrate_del_blocker(vbasedev->migration_blocker);
+        error_free(vbasedev->migration_blocker);
+        vbasedev->migration_blocker = NULL;
+    }
+}

diff --git a/hw/vfio/trace-events b/hw/vfio/trace-events
index a0c7b49a2ebc3d1af37b871c1591b059da13d07a..9ced5ec6277cb4c1d5e500eb660810442c79dc53 100644 (file)
--- a/hw/vfio/trace-events
+++ b/hw/vfio/trace-events
@@ -145,3 +145,6 @@ vfio_display_edid_link_up(void) ""
 vfio_display_edid_link_down(void) ""
 vfio_display_edid_update(uint32_t prefx, uint32_t prefy) "%ux%u"
 vfio_display_edid_write_error(void) ""
+
+# migration.c
+vfio_migration_probe(const char *name, uint32_t index) " (%s) Region %d"

diff --git a/include/hw/vfio/vfio-common.h b/include/hw/vfio/vfio-common.h
index ba6169cd926ed872aee49d966e00f4ee8045b206..8275c4c68f450b9c3b5b6f4e2b7bcedee0c96ca5 100644 (file)
--- a/include/hw/vfio/vfio-common.h
+++ b/include/hw/vfio/vfio-common.h
@@ -57,6 +57,10 @@ typedef struct VFIORegion {
     uint8_t nr; /* cache the region number for debug */
 } VFIORegion;
 
+typedef struct VFIOMigration {
+    VFIORegion region;
+} VFIOMigration;
+
 typedef struct VFIOAddressSpace {
     AddressSpace *as;
     QLIST_HEAD(, VFIOContainer) containers;
@@ -113,6 +117,8 @@ typedef struct VFIODevice {
     unsigned int num_irqs;
     unsigned int num_regions;
     unsigned int flags;
+    VFIOMigration *migration;
+    Error *migration_blocker;
 } VFIODevice;
 
 struct VFIODeviceOps {
@@ -204,4 +210,7 @@ int vfio_spapr_create_window(VFIOContainer *container,
 int vfio_spapr_remove_window(VFIOContainer *container,
                              hwaddr offset_within_address_space);
 
+int vfio_migration_probe(VFIODevice *vbasedev, Error **errp);
+void vfio_migration_finalize(VFIODevice *vbasedev);
+
 #endif /* HW_VFIO_VFIO_COMMON_H */