[Qemu-devel] [PATCH 1/3] vfio/pci: conversion to realize

[Eric Auger]

This patch converts VFIO PCI to realize function.

Also original initfn errors now are propagated using QEMU
error objects. All errors are formatted with the same pattern:
"vfio: %s: the error description"

Subsequent patches will pass the error objects to
- vfio_populate_device,
- vfio_msix_early_setup.

At this point if those functions fail let's just report an error
at realize level.

Signed-off-by: Eric Auger <address@hidden>
---
 hw/vfio/pci.c        | 81 ++++++++++++++++++++++++++++------------------------
 hw/vfio/trace-events |  2 +-
 2 files changed, 44 insertions(+), 39 deletions(-)

diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
index 7bfa17c..ae1967c 100644
--- a/hw/vfio/pci.c
+++ b/hw/vfio/pci.c
@@ -2485,7 +2485,7 @@ static void vfio_unregister_req_notifier(VFIOPCIDevice 
*vdev)
     vdev->req_enabled = false;
 }
 
-static int vfio_initfn(PCIDevice *pdev)
+static void vfio_realize(PCIDevice *pdev, Error **errp)
 {
     VFIOPCIDevice *vdev = DO_UPCAST(VFIOPCIDevice, pdev, pdev);
     VFIODevice *vbasedev_iter;
@@ -2504,9 +2504,9 @@ static int vfio_initfn(PCIDevice *pdev)
     }
 
     if (stat(vdev->vbasedev.sysfsdev, &st) < 0) {
-        error_report("vfio: error: no such host device: %s",
-                     vdev->vbasedev.sysfsdev);
-        return -errno;
+        error_setg_errno(errp, -errno, "vfio: error: no such host device: %s",
+                         vdev->vbasedev.sysfsdev);
+        return;
     }
 
     vdev->vbasedev.name = g_strdup(basename(vdev->vbasedev.sysfsdev));
@@ -2518,45 +2518,46 @@ static int vfio_initfn(PCIDevice *pdev)
     g_free(tmp);
 
     if (len <= 0 || len >= sizeof(group_path)) {
-        error_report("vfio: error no iommu_group for device");
-        return len < 0 ? -errno : -ENAMETOOLONG;
+        error_setg_errno(errp, len < 0 ? -errno : -ENAMETOOLONG,
+                         "no iommu_group found");
+        goto error;
     }
 
     group_path[len] = 0;
 
     group_name = basename(group_path);
     if (sscanf(group_name, "%d", &groupid) != 1) {
-        error_report("vfio: error reading %s: %m", group_path);
-        return -errno;
+        error_setg_errno(errp, -errno, "failed to read %s", group_path);
+        goto error;
     }
 
-    trace_vfio_initfn(vdev->vbasedev.name, groupid);
+    trace_vfio_realize(vdev->vbasedev.name, groupid);
 
     group = vfio_get_group(groupid, pci_device_iommu_address_space(pdev));
     if (!group) {
-        error_report("vfio: failed to get group %d", groupid);
-        return -ENOENT;
+        error_setg_errno(errp, -ENOENT, "failed to get group %d", groupid);
+        goto error;
     }
 
     QLIST_FOREACH(vbasedev_iter, &group->device_list, next) {
         if (strcmp(vbasedev_iter->name, vdev->vbasedev.name) == 0) {
-            error_report("vfio: error: device %s is already attached",
-                         vdev->vbasedev.name);
+            error_setg_errno(errp, -EBUSY, "device is already attached");
             vfio_put_group(group);
-            return -EBUSY;
+            goto error;
         }
     }
 
     ret = vfio_get_device(group, vdev->vbasedev.name, &vdev->vbasedev);
     if (ret) {
-        error_report("vfio: failed to get device %s", vdev->vbasedev.name);
+        error_setg_errno(errp, ret, "failed to get the device");
         vfio_put_group(group);
-        return ret;
+        goto error;
     }
 
     ret = vfio_populate_device(vdev);
     if (ret) {
-        return ret;
+        error_setg_errno(errp, ret, "failed to populate the device");
+        goto error;
     }
 
     /* Get a copy of config space */
@@ -2565,8 +2566,8 @@ static int vfio_initfn(PCIDevice *pdev)
                 vdev->config_offset);
     if (ret < (int)MIN(pci_config_size(&vdev->pdev), vdev->config_size)) {
         ret = ret < 0 ? -errno : -EFAULT;
-        error_report("vfio: Failed to read device config space");
-        return ret;
+        error_setg_errno(errp, ret, "failed to read device config space");
+        goto error;
     }
 
     /* vfio emulates a lot for us, but some bits need extra love */
@@ -2582,8 +2583,8 @@ static int vfio_initfn(PCIDevice *pdev)
      */
     if (vdev->vendor_id != PCI_ANY_ID) {
         if (vdev->vendor_id >= 0xffff) {
-            error_report("vfio: Invalid PCI vendor ID provided");
-            return -EINVAL;
+            error_setg_errno(errp, -EINVAL, "invalid PCI vendor ID provided");
+            goto error;
         }
         vfio_add_emulated_word(vdev, PCI_VENDOR_ID, vdev->vendor_id, ~0);
         trace_vfio_pci_emulated_vendor_id(vdev->vbasedev.name, 
vdev->vendor_id);
@@ -2593,8 +2594,8 @@ static int vfio_initfn(PCIDevice *pdev)
 
     if (vdev->device_id != PCI_ANY_ID) {
         if (vdev->device_id > 0xffff) {
-            error_report("vfio: Invalid PCI device ID provided");
-            return -EINVAL;
+            error_setg_errno(errp, -EINVAL, "invalid PCI device ID provided");
+            goto error;
         }
         vfio_add_emulated_word(vdev, PCI_DEVICE_ID, vdev->device_id, ~0);
         trace_vfio_pci_emulated_device_id(vdev->vbasedev.name, 
vdev->device_id);
@@ -2604,8 +2605,9 @@ static int vfio_initfn(PCIDevice *pdev)
 
     if (vdev->sub_vendor_id != PCI_ANY_ID) {
         if (vdev->sub_vendor_id > 0xffff) {
-            error_report("vfio: Invalid PCI subsystem vendor ID provided");
-            return -EINVAL;
+            error_setg_errno(errp, -EINVAL,
+                             "invalid PCI subsystem vendor ID provided");
+            goto error;
         }
         vfio_add_emulated_word(vdev, PCI_SUBSYSTEM_VENDOR_ID,
                                vdev->sub_vendor_id, ~0);
@@ -2615,8 +2617,9 @@ static int vfio_initfn(PCIDevice *pdev)
 
     if (vdev->sub_device_id != PCI_ANY_ID) {
         if (vdev->sub_device_id > 0xffff) {
-            error_report("vfio: Invalid PCI subsystem device ID provided");
-            return -EINVAL;
+            error_setg_errno(errp, -EINVAL,
+                             "invalid PCI subsystem device ID provided");
+            goto error;
         }
         vfio_add_emulated_word(vdev, PCI_SUBSYSTEM_ID, vdev->sub_device_id, 
~0);
         trace_vfio_pci_emulated_sub_device_id(vdev->vbasedev.name,
@@ -2646,7 +2649,8 @@ static int vfio_initfn(PCIDevice *pdev)
 
     ret = vfio_msix_early_setup(vdev);
     if (ret) {
-        return ret;
+        error_setg_errno(errp, ret, "msix early setup failure");
+        goto error;
     }
 
     vfio_bars_setup(vdev);
@@ -2669,9 +2673,9 @@ static int vfio_initfn(PCIDevice *pdev)
         struct vfio_region_info *opregion;
 
         if (vdev->pdev.qdev.hotplugged) {
-            error_report("Cannot support IGD OpRegion feature on hotplugged "
-                         "device %s", vdev->vbasedev.name);
-            ret = -EINVAL;
+            error_setg_errno(errp, -EINVAL,
+                       "cannot support IGD OpRegion feature on hotplugged "
+                       "device");
             goto out_teardown;
         }
 
@@ -2679,16 +2683,15 @@ static int vfio_initfn(PCIDevice *pdev)
                         VFIO_REGION_TYPE_PCI_VENDOR_TYPE | PCI_VENDOR_ID_INTEL,
                         VFIO_REGION_SUBTYPE_INTEL_IGD_OPREGION, &opregion);
         if (ret) {
-            error_report("Device %s does not support requested IGD OpRegion "
-                         "feature", vdev->vbasedev.name);
+            error_setg_errno(errp, ret,
+                       "does not support requested IGD OpRegion feature");
             goto out_teardown;
         }
 
         ret = vfio_pci_igd_opregion_init(vdev, opregion);
         g_free(opregion);
         if (ret) {
-            error_report("Device %s IGD OpRegion initialization failed",
-                         vdev->vbasedev.name);
+            error_setg_errno(errp, ret, "IGD OpRegion initialization failed");
             goto out_teardown;
         }
     }
@@ -2710,6 +2713,7 @@ static int vfio_initfn(PCIDevice *pdev)
         pci_device_set_intx_routing_notifier(&vdev->pdev, vfio_intx_update);
         ret = vfio_intx_enable(vdev);
         if (ret) {
+            error_setg_errno(errp, ret, "failed to enable intx");
             goto out_teardown;
         }
     }
@@ -2718,13 +2722,14 @@ static int vfio_initfn(PCIDevice *pdev)
     vfio_register_req_notifier(vdev);
     vfio_setup_resetfn_quirk(vdev);
 
-    return 0;
+    return;
 
 out_teardown:
     pci_device_set_intx_routing_notifier(&vdev->pdev, NULL);
     vfio_teardown_msi(vdev);
     vfio_bars_exit(vdev);
-    return ret;
+error:
+    error_prepend(errp, "vfio: %s: ", vdev->vbasedev.name);
 }
 
 static void vfio_instance_finalize(Object *obj)
@@ -2853,7 +2858,7 @@ static void vfio_pci_dev_class_init(ObjectClass *klass, 
void *data)
     dc->vmsd = &vfio_pci_vmstate;
     dc->desc = "VFIO-based PCI device assignment";
     set_bit(DEVICE_CATEGORY_MISC, dc->categories);
-    pdc->init = vfio_initfn;
+    pdc->realize = vfio_realize;
     pdc->exit = vfio_exitfn;
     pdc->config_read = vfio_pci_read_config;
     pdc->config_write = vfio_pci_write_config;
diff --git a/hw/vfio/trace-events b/hw/vfio/trace-events
index 4bb7690..14e3fc4 100644
--- a/hw/vfio/trace-events
+++ b/hw/vfio/trace-events
@@ -36,7 +36,7 @@ vfio_pci_hot_reset_dep_devices(int domain, int bus, int slot, 
int function, int
 vfio_pci_hot_reset_result(const char *name, const char *result) "%s hot reset: 
%s"
 vfio_populate_device_config(const char *name, unsigned long size, unsigned 
long offset, unsigned long flags) "Device %s config:\n  size: 0x%lx, offset: 
0x%lx, flags: 0x%lx"
 vfio_populate_device_get_irq_info_failure(void) "VFIO_DEVICE_GET_IRQ_INFO 
failure: %m"
-vfio_initfn(const char *name, int group_id) " (%s) group %d"
+vfio_realize(const char *name, int group_id) " (%s) group %d"
 vfio_add_ext_cap_dropped(const char *name, uint16_t cap, uint16_t offset) "%s 
address@hidden"
 vfio_pci_reset(const char *name) " (%s)"
 vfio_pci_reset_flr(const char *name) "%s FLR/VFIO_DEVICE_RESET"
-- 
1.9.1