[Qemu-devel] [RFC PATCH v5 3/7] vfio/pci: Fix return of vfio_populate_vga()

[Alex Williamson <alex.williamson@redhat.com>]

This function returns success if either we setup the VGA region or
the host vfio doesn't return enough regions to support the VGA index.
This latter case doesn't make any sense.  If we're asked to populate
VGA, fail if it doesn't exist and let the caller decide if that's
important.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
---
 hw/vfio/pci.c |   55 ++++++++++++++++++++++++++-----------------------------
 1 file changed, 26 insertions(+), 29 deletions(-)

diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
index d091d8c..dfce313 100644
--- a/hw/vfio/pci.c
+++ b/hw/vfio/pci.c
@@ -2061,42 +2061,39 @@ int vfio_populate_vga(VFIOPCIDevice *vdev)
     struct vfio_region_info *reg_info;
     int ret;
 
-    if (vbasedev->num_regions > VFIO_PCI_VGA_REGION_INDEX) {
-        ret = vfio_get_region_info(vbasedev,
-                                   VFIO_PCI_VGA_REGION_INDEX, &reg_info);
-        if (ret) {
-            return ret;
-        }
+    ret = vfio_get_region_info(vbasedev, VFIO_PCI_VGA_REGION_INDEX, &reg_info);
+    if (ret) {
+        return ret;
+    }
 
-        if (!(reg_info->flags & VFIO_REGION_INFO_FLAG_READ) ||
-            !(reg_info->flags & VFIO_REGION_INFO_FLAG_WRITE) ||
-            reg_info->size < 0xbffff + 1) {
-            error_report("vfio: Unexpected VGA info, flags 0x%lx, size 0x%lx",
-                         (unsigned long)reg_info->flags,
-                         (unsigned long)reg_info->size);
-            g_free(reg_info);
-            return -EINVAL;
-        }
+    if (!(reg_info->flags & VFIO_REGION_INFO_FLAG_READ) ||
+        !(reg_info->flags & VFIO_REGION_INFO_FLAG_WRITE) ||
+        reg_info->size < 0xbffff + 1) {
+        error_report("vfio: Unexpected VGA info, flags 0x%lx, size 0x%lx",
+                     (unsigned long)reg_info->flags,
+                     (unsigned long)reg_info->size);
+        g_free(reg_info);
+        return -EINVAL;
+    }
 
-        vdev->vga = g_new0(VFIOVGA, 1);
+    vdev->vga = g_new0(VFIOVGA, 1);
 
-        vdev->vga->fd_offset = reg_info->offset;
-        vdev->vga->fd = vdev->vbasedev.fd;
+    vdev->vga->fd_offset = reg_info->offset;
+    vdev->vga->fd = vdev->vbasedev.fd;
 
-        g_free(reg_info);
+    g_free(reg_info);
 
-        vdev->vga->region[QEMU_PCI_VGA_MEM].offset = QEMU_PCI_VGA_MEM_BASE;
-        vdev->vga->region[QEMU_PCI_VGA_MEM].nr = QEMU_PCI_VGA_MEM;
-        QLIST_INIT(&vdev->vga->region[QEMU_PCI_VGA_MEM].quirks);
+    vdev->vga->region[QEMU_PCI_VGA_MEM].offset = QEMU_PCI_VGA_MEM_BASE;
+    vdev->vga->region[QEMU_PCI_VGA_MEM].nr = QEMU_PCI_VGA_MEM;
+    QLIST_INIT(&vdev->vga->region[QEMU_PCI_VGA_MEM].quirks);
 
-        vdev->vga->region[QEMU_PCI_VGA_IO_LO].offset = QEMU_PCI_VGA_IO_LO_BASE;
-        vdev->vga->region[QEMU_PCI_VGA_IO_LO].nr = QEMU_PCI_VGA_IO_LO;
-        QLIST_INIT(&vdev->vga->region[QEMU_PCI_VGA_IO_LO].quirks);
+    vdev->vga->region[QEMU_PCI_VGA_IO_LO].offset = QEMU_PCI_VGA_IO_LO_BASE;
+    vdev->vga->region[QEMU_PCI_VGA_IO_LO].nr = QEMU_PCI_VGA_IO_LO;
+    QLIST_INIT(&vdev->vga->region[QEMU_PCI_VGA_IO_LO].quirks);
 
-        vdev->vga->region[QEMU_PCI_VGA_IO_HI].offset = QEMU_PCI_VGA_IO_HI_BASE;
-        vdev->vga->region[QEMU_PCI_VGA_IO_HI].nr = QEMU_PCI_VGA_IO_HI;
-        QLIST_INIT(&vdev->vga->region[QEMU_PCI_VGA_IO_HI].quirks);
-    }
+    vdev->vga->region[QEMU_PCI_VGA_IO_HI].offset = QEMU_PCI_VGA_IO_HI_BASE;
+    vdev->vga->region[QEMU_PCI_VGA_IO_HI].nr = QEMU_PCI_VGA_IO_HI;
+    QLIST_INIT(&vdev->vga->region[QEMU_PCI_VGA_IO_HI].quirks);
 
     return 0;
 }