[Qemu-devel] [PATCH v2 2/4] hw: Propagate errors through qdev_prop_set_drive()

[Markus Armbruster]

Three kinds of callers:

1. On failure, report the error and abort

   Passing &error_abort does the job.  No functional change.

2. On failure, report the error and exit()

   This is qdev_prop_set_drive_nofail().  Error reporting moves from
   qdev_prop_set_drive() to its caller.  Because hiding away the error
   in the monitor right before exit() isn't helpful, replace
   qerror_report_err() by error_report_err().  Shouldn't make a
   difference, because qdev_prop_set_drive_nofail() should never be
   used in QMP context.

3. On failure, report the error and recover

   This is usb_msd_init() and scsi_bus_legacy_add_drive().  Error
   reporting and freeing the error object moves from
   qdev_prop_set_drive() to its callers.

   Because usb_msd_init() can't run in QMP context, replace
   qerror_report_err() by error_report_err() there.

   No functional change.

   scsi_bus_legacy_add_drive() calling qerror_report_err() is of
   course inappropriate, but this commit merely makes it more obvious.
   The next one will clean it up.

Signed-off-by: Markus Armbruster <address@hidden>
Reviewed-by: Peter Crosthwaite <address@hidden>
---
 hw/arm/vexpress.c                |  6 +++---
 hw/arm/virt.c                    |  6 +++---
 hw/block/pflash_cfi01.c          |  4 ++--
 hw/block/pflash_cfi02.c          |  4 ++--
 hw/core/qdev-properties-system.c | 22 ++++++++++------------
 hw/scsi/scsi-bus.c               |  6 +++++-
 hw/usb/dev-storage.c             |  7 +++++--
 include/hw/qdev-properties.h     |  4 ++--
 8 files changed, 32 insertions(+), 27 deletions(-)

diff --git a/hw/arm/vexpress.c b/hw/arm/vexpress.c
index 5933454..8496c16 100644
--- a/hw/arm/vexpress.c
+++ b/hw/arm/vexpress.c
@@ -515,9 +515,9 @@ static pflash_t *ve_pflash_cfi01_register(hwaddr base, 
const char *name,
 {
     DeviceState *dev = qdev_create(NULL, "cfi.pflash01");
 
-    if (di && qdev_prop_set_drive(dev, "drive",
-                                  blk_by_legacy_dinfo(di))) {
-        abort();
+    if (di) {
+        qdev_prop_set_drive(dev, "drive", blk_by_legacy_dinfo(di),
+                            &error_abort);
     }
 
     qdev_prop_set_uint32(dev, "num-blocks",
diff --git a/hw/arm/virt.c b/hw/arm/virt.c
index 69f51ac..93b7605 100644
--- a/hw/arm/virt.c
+++ b/hw/arm/virt.c
@@ -522,9 +522,9 @@ static void create_one_flash(const char *name, hwaddr 
flashbase,
     DeviceState *dev = qdev_create(NULL, "cfi.pflash01");
     const uint64_t sectorlength = 256 * 1024;
 
-    if (dinfo && qdev_prop_set_drive(dev, "drive",
-                                     blk_by_legacy_dinfo(dinfo))) {
-        abort();
+    if (dinfo) {
+        qdev_prop_set_drive(dev, "drive", blk_by_legacy_dinfo(dinfo),
+                            &error_abort);
     }
 
     qdev_prop_set_uint32(dev, "num-blocks", flashsize / sectorlength);
diff --git a/hw/block/pflash_cfi01.c b/hw/block/pflash_cfi01.c
index 89d380e..d282695 100644
--- a/hw/block/pflash_cfi01.c
+++ b/hw/block/pflash_cfi01.c
@@ -969,8 +969,8 @@ pflash_t *pflash_cfi01_register(hwaddr base,
 {
     DeviceState *dev = qdev_create(NULL, TYPE_CFI_PFLASH01);
 
-    if (blk && qdev_prop_set_drive(dev, "drive", blk)) {
-        abort();
+    if (blk) {
+        qdev_prop_set_drive(dev, "drive", blk, &error_abort);
     }
     qdev_prop_set_uint32(dev, "num-blocks", nb_blocs);
     qdev_prop_set_uint64(dev, "sector-length", sector_len);
diff --git a/hw/block/pflash_cfi02.c b/hw/block/pflash_cfi02.c
index 389b4aa..074a005 100644
--- a/hw/block/pflash_cfi02.c
+++ b/hw/block/pflash_cfi02.c
@@ -773,8 +773,8 @@ pflash_t *pflash_cfi02_register(hwaddr base,
 {
     DeviceState *dev = qdev_create(NULL, TYPE_CFI_PFLASH02);
 
-    if (blk && qdev_prop_set_drive(dev, "drive", blk)) {
-        abort();
+    if (blk) {
+        qdev_prop_set_drive(dev, "drive", blk, &error_abort);
     }
     qdev_prop_set_uint32(dev, "num-blocks", nb_blocs);
     qdev_prop_set_uint32(dev, "sector-length", sector_len);
diff --git a/hw/core/qdev-properties-system.c b/hw/core/qdev-properties-system.c
index a2e44bd..c413226 100644
--- a/hw/core/qdev-properties-system.c
+++ b/hw/core/qdev-properties-system.c
@@ -341,27 +341,25 @@ PropertyInfo qdev_prop_vlan = {
     .set   = set_vlan,
 };
 
-int qdev_prop_set_drive(DeviceState *dev, const char *name,
-                        BlockBackend *value)
+void qdev_prop_set_drive(DeviceState *dev, const char *name,
+                         BlockBackend *value, Error **errp)
 {
-    Error *err = NULL;
-    object_property_set_str(OBJECT(dev),
-                            value ? blk_name(value) : "", name, &err);
-    if (err) {
-        qerror_report_err(err);
-        error_free(err);
-        return -1;
-    }
-    return 0;
+    object_property_set_str(OBJECT(dev), value ? blk_name(value) : "",
+                            name, errp);
 }
 
 void qdev_prop_set_drive_nofail(DeviceState *dev, const char *name,
                                 BlockBackend *value)
 {
-    if (qdev_prop_set_drive(dev, name, value) < 0) {
+    Error *err = NULL;
+
+    qdev_prop_set_drive(dev, name, value, &err);
+    if (err) {
+        error_report_err(err);
         exit(1);
     }
 }
+
 void qdev_prop_set_chr(DeviceState *dev, const char *name,
                        CharDriverState *value)
 {
diff --git a/hw/scsi/scsi-bus.c b/hw/scsi/scsi-bus.c
index f8de569..61c595f 100644
--- a/hw/scsi/scsi-bus.c
+++ b/hw/scsi/scsi-bus.c
@@ -7,6 +7,7 @@
 #include "sysemu/blockdev.h"
 #include "trace.h"
 #include "sysemu/dma.h"
+#include "qapi/qmp/qerror.h"
 
 static char *scsibus_get_dev_path(DeviceState *dev);
 static char *scsibus_get_fw_dev_path(DeviceState *dev);
@@ -242,7 +243,10 @@ SCSIDevice *scsi_bus_legacy_add_drive(SCSIBus *bus, 
BlockBackend *blk,
     if (serial && object_property_find(OBJECT(dev), "serial", NULL)) {
         qdev_prop_set_string(dev, "serial", serial);
     }
-    if (qdev_prop_set_drive(dev, "drive", blk) < 0) {
+    qdev_prop_set_drive(dev, "drive", blk, &err);
+    if (err) {
+        qerror_report_err(err);
+        error_free(err);
         error_setg(errp, "Setting drive property failed");
         object_unparent(OBJECT(dev));
         return NULL;
diff --git a/hw/usb/dev-storage.c b/hw/usb/dev-storage.c
index 65d9aa6..3f5b32d 100644
--- a/hw/usb/dev-storage.c
+++ b/hw/usb/dev-storage.c
@@ -663,6 +663,7 @@ static void usb_msd_realize_bot(USBDevice *dev, Error 
**errp)
 static USBDevice *usb_msd_init(USBBus *bus, const char *filename)
 {
     static int nr=0;
+    Error *err = NULL;
     char id[8];
     QemuOpts *opts;
     DriveInfo *dinfo;
@@ -706,8 +707,10 @@ static USBDevice *usb_msd_init(USBBus *bus, const char 
*filename)
 
     /* create guest device */
     dev = usb_create(bus, "usb-storage");
-    if (qdev_prop_set_drive(&dev->qdev, "drive",
-                            blk_by_legacy_dinfo(dinfo)) < 0) {
+    qdev_prop_set_drive(&dev->qdev, "drive", blk_by_legacy_dinfo(dinfo),
+                        &err);
+    if (err) {
+        error_report_err(err);
         object_unparent(OBJECT(dev));
         return NULL;
     }
diff --git a/include/hw/qdev-properties.h b/include/hw/qdev-properties.h
index 57ee363..2d47c0c 100644
--- a/include/hw/qdev-properties.h
+++ b/include/hw/qdev-properties.h
@@ -168,8 +168,8 @@ void qdev_prop_set_uint64(DeviceState *dev, const char 
*name, uint64_t value);
 void qdev_prop_set_string(DeviceState *dev, const char *name, const char 
*value);
 void qdev_prop_set_chr(DeviceState *dev, const char *name, CharDriverState 
*value);
 void qdev_prop_set_netdev(DeviceState *dev, const char *name, NetClientState 
*value);
-int qdev_prop_set_drive(DeviceState *dev, const char *name,
-                        BlockBackend *value) QEMU_WARN_UNUSED_RESULT;
+void qdev_prop_set_drive(DeviceState *dev, const char *name,
+                         BlockBackend *value, Error **errp);
 void qdev_prop_set_drive_nofail(DeviceState *dev, const char *name,
                                 BlockBackend *value);
 void qdev_prop_set_macaddr(DeviceState *dev, const char *name, uint8_t *value);
-- 
1.9.3