From: Ankit Agrawal <ankita@nvidia.com>

Add an Error **errp parameter to vfio_region_setup() and
vfio_setup_region_sparse_mmaps to allow proper error handling
instead of just returning error codes.

The function sets errors via error_setg() when failure occur.

Suggested-by: Cedric Le Goater <clg@redhat.com>
Signed-off-by: Ankit Agrawal <ankita@nvidia.com>
---
 hw/vfio/display.c     |  6 +++---
 hw/vfio/pci.c         |  3 +--
 hw/vfio/region.c      | 20 +++++++++++---------
 hw/vfio/vfio-region.h |  2 +-
 4 files changed, 16 insertions(+), 15 deletions(-)

diff --git a/hw/vfio/display.c b/hw/vfio/display.c
index faacd9019a..5a42a6f7a2 100644
--- a/hw/vfio/display.c
+++ b/hw/vfio/display.c
@@ -446,13 +446,13 @@ static void vfio_display_region_update(void *opaque)
 
     if (!dpy->region.buffer.size) {
         /* mmap region */
+        Error *error = NULL;
         ret = vfio_region_setup(OBJECT(vdev), &vdev->vbasedev,
                                 &dpy->region.buffer,
                                 plane.region_index,
-                                "display");
+                                "display", &error);
         if (ret != 0) {
-            error_report("%s: vfio_region_setup(%d): %s",
-                         __func__, plane.region_index, strerror(-ret));
+            error_report_err(error);
             goto err;
         }
         ret = vfio_region_mmap(&dpy->region.buffer);
diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
index 36d8fbe872..c89f3fbea3 100644
--- a/hw/vfio/pci.c
+++ b/hw/vfio/pci.c
@@ -3056,11 +3056,10 @@ bool vfio_pci_populate_device(VFIOPCIDevice *vdev, Error **errp)
         char *name = g_strdup_printf("%s BAR %d", vbasedev->name, i);
 
         ret = vfio_region_setup(OBJECT(vdev), vbasedev,
-                                &vdev->bars[i].region, i, name);
+                                &vdev->bars[i].region, i, name, errp);
         g_free(name);
 
         if (ret) {
-            error_setg_errno(errp, -ret, "failed to get region %d info", i);
             return false;
         }
 
diff --git a/hw/vfio/region.c b/hw/vfio/region.c
index 8fbc98918f..d464eadf9c 100644
--- a/hw/vfio/region.c
+++ b/hw/vfio/region.c
@@ -163,7 +163,8 @@ static int vfio_mmap_compare_offset(const void *a, const void *b)
 }
 
 static int vfio_setup_region_sparse_mmaps(VFIORegion *region,
-                                          struct vfio_region_info *info)
+                                          struct vfio_region_info *info,
+                                          Error **errp)
 {
     struct vfio_info_cap_header *hdr;
     struct vfio_region_info_cap_sparse_mmap *sparse;
@@ -210,12 +211,12 @@ static int vfio_setup_region_sparse_mmaps(VFIORegion *region,
             off_t prev_end = region->mmaps[i - 1].offset +
                              region->mmaps[i - 1].size;
             if (prev_end > region->mmaps[i].offset) {
-                error_report("%s: overlapping sparse mmap regions detected "
-                             "in region %d: [0x%"PRIx64"-0x%"PRIx64"] overlaps "
-                             "with [0x%"PRIx64"-0x%"PRIx64"]",
-                             __func__, region->nr, region->mmaps[i - 1].offset,
-                             prev_end - 1, region->mmaps[i].offset,
-                             region->mmaps[i].offset + region->mmaps[i].size - 1);
+                error_setg(errp, "%s: overlapping sparse mmap regions detected "
+                           "in region %d: [0x%"PRIx64"-0x%"PRIx64"] overlaps "
+                           "with [0x%"PRIx64"-0x%"PRIx64"]",
+                           __func__, region->nr, region->mmaps[i - 1].offset,
+                           prev_end - 1, region->mmaps[i].offset,
+                           region->mmaps[i].offset + region->mmaps[i].size - 1);
                 g_free(region->mmaps);
                 region->mmaps = NULL;
                 region->nr_mmaps = 0;
@@ -228,13 +229,14 @@ static int vfio_setup_region_sparse_mmaps(VFIORegion *region,
 }
 
 int vfio_region_setup(Object *obj, VFIODevice *vbasedev, VFIORegion *region,
-                      int index, const char *name)
+                      int index, const char *name, Error **errp)
 {
     struct vfio_region_info *info = NULL;
     int ret;
 
     ret = vfio_device_get_region_info(vbasedev, index, &info);
     if (ret) {
+        error_setg_errno(errp, -ret, "failed to get region %d info", index);
         return ret;
     }
 
@@ -253,7 +255,7 @@ int vfio_region_setup(Object *obj, VFIODevice *vbasedev, VFIORegion *region,
         if (!vbasedev->no_mmap &&
             region->flags & VFIO_REGION_INFO_FLAG_MMAP) {
 
-            ret = vfio_setup_region_sparse_mmaps(region, info);
+            ret = vfio_setup_region_sparse_mmaps(region, info, errp);
 
             if (ret == -ENODEV) {
                 region->nr_mmaps = 1;
diff --git a/hw/vfio/vfio-region.h b/hw/vfio/vfio-region.h
index ede6e0c8f9..9b21d4ee5b 100644
--- a/hw/vfio/vfio-region.h
+++ b/hw/vfio/vfio-region.h
@@ -38,7 +38,7 @@ void vfio_region_write(void *opaque, hwaddr addr,
 uint64_t vfio_region_read(void *opaque,
                           hwaddr addr, unsigned size);
 int vfio_region_setup(Object *obj, VFIODevice *vbasedev, VFIORegion *region,
-                      int index, const char *name);
+                      int index, const char *name, Error **errp);
 int vfio_region_mmap(VFIORegion *region);
 void vfio_region_mmaps_set_enabled(VFIORegion *region, bool enabled);
 void vfio_region_unmap(VFIORegion *region);
-- 
2.34.1