Re: [Qemu-devel] [PATCH v8 05/16] virtio-scsi: Catch BDS-BB removal/insertion

2016-01-29 Thread Max Reitz
On 29.01.2016 13:41, Kevin Wolf wrote:
> Am 27.01.2016 um 18:59 hat Max Reitz geschrieben:
>> Make use of the BDS-BB removal and insertion notifiers to remove or set
>> up, respectively, virtio-scsi's op blockers.
>>
>> Signed-off-by: Max Reitz 
>> ---
>>  hw/scsi/virtio-scsi.c   | 55 
>> +
>>  include/hw/virtio/virtio-scsi.h | 10 
>>  2 files changed, 65 insertions(+)
>>
>> diff --git a/hw/scsi/virtio-scsi.c b/hw/scsi/virtio-scsi.c
>> index 607593c..b508b81 100644
>> --- a/hw/scsi/virtio-scsi.c
>> +++ b/hw/scsi/virtio-scsi.c
>> @@ -757,6 +757,22 @@ static void virtio_scsi_change(SCSIBus *bus, SCSIDevice 
>> *dev, SCSISense sense)
>>  }
>>  }
>>  
>> +static void virtio_scsi_blk_insert_notifier(Notifier *n, void *data)
>> +{
>> +VirtIOSCSIBlkChangeNotifier *cn = DO_UPCAST(VirtIOSCSIBlkChangeNotifier,
>> +n, n);
>> +assert(cn->sd->conf.blk == data);
>> +blk_op_block_all(cn->sd->conf.blk, cn->s->blocker);
>> +}
>> +
>> +static void virtio_scsi_blk_remove_notifier(Notifier *n, void *data)
>> +{
>> +VirtIOSCSIBlkChangeNotifier *cn = DO_UPCAST(VirtIOSCSIBlkChangeNotifier,
>> +n, n);
>> +assert(cn->sd->conf.blk == data);
>> +blk_op_unblock_all(cn->sd->conf.blk, cn->s->blocker);
>> +}
>> +
>>  static void virtio_scsi_hotplug(HotplugHandler *hotplug_dev, DeviceState 
>> *dev,
>>  Error **errp)
>>  {
>> @@ -765,6 +781,22 @@ static void virtio_scsi_hotplug(HotplugHandler 
>> *hotplug_dev, DeviceState *dev,
>>  SCSIDevice *sd = SCSI_DEVICE(dev);
>>  
>>  if (s->ctx && !s->dataplane_disabled) {
>> +VirtIOSCSIBlkChangeNotifier *insert_notifier, *remove_notifier;
>> +
>> +insert_notifier = g_new0(VirtIOSCSIBlkChangeNotifier, 1);
>> +insert_notifier->n.notify = virtio_scsi_blk_insert_notifier;
>> +insert_notifier->s = s;
>> +insert_notifier->sd = sd;
>> +blk_add_insert_bs_notifier(sd->conf.blk, _notifier->n);
>> +QTAILQ_INSERT_TAIL(>insert_notifiers, insert_notifier, next);
>> +
>> +remove_notifier = g_new0(VirtIOSCSIBlkChangeNotifier, 1);
>> +remove_notifier->n.notify = virtio_scsi_blk_remove_notifier;
>> +remove_notifier->s = s;
>> +remove_notifier->sd = sd;
>> +blk_add_remove_bs_notifier(sd->conf.blk, _notifier->n);
>> +QTAILQ_INSERT_TAIL(>remove_notifiers, remove_notifier, next);
>> +
>>  if (blk_op_is_blocked(sd->conf.blk, BLOCK_OP_TYPE_DATAPLANE, errp)) 
>> {
>>  return;
>>  }
> 
> If we take the error path here, won't we have dangling pointers in the
> notifier list?

Yes, I'll move it below that error path.

Max



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Re: [Qemu-devel] [PATCH v8 05/16] virtio-scsi: Catch BDS-BB removal/insertion

2016-01-29 Thread Kevin Wolf
Am 27.01.2016 um 18:59 hat Max Reitz geschrieben:
> Make use of the BDS-BB removal and insertion notifiers to remove or set
> up, respectively, virtio-scsi's op blockers.
> 
> Signed-off-by: Max Reitz 
> ---
>  hw/scsi/virtio-scsi.c   | 55 
> +
>  include/hw/virtio/virtio-scsi.h | 10 
>  2 files changed, 65 insertions(+)
> 
> diff --git a/hw/scsi/virtio-scsi.c b/hw/scsi/virtio-scsi.c
> index 607593c..b508b81 100644
> --- a/hw/scsi/virtio-scsi.c
> +++ b/hw/scsi/virtio-scsi.c
> @@ -757,6 +757,22 @@ static void virtio_scsi_change(SCSIBus *bus, SCSIDevice 
> *dev, SCSISense sense)
>  }
>  }
>  
> +static void virtio_scsi_blk_insert_notifier(Notifier *n, void *data)
> +{
> +VirtIOSCSIBlkChangeNotifier *cn = DO_UPCAST(VirtIOSCSIBlkChangeNotifier,
> +n, n);
> +assert(cn->sd->conf.blk == data);
> +blk_op_block_all(cn->sd->conf.blk, cn->s->blocker);
> +}
> +
> +static void virtio_scsi_blk_remove_notifier(Notifier *n, void *data)
> +{
> +VirtIOSCSIBlkChangeNotifier *cn = DO_UPCAST(VirtIOSCSIBlkChangeNotifier,
> +n, n);
> +assert(cn->sd->conf.blk == data);
> +blk_op_unblock_all(cn->sd->conf.blk, cn->s->blocker);
> +}
> +
>  static void virtio_scsi_hotplug(HotplugHandler *hotplug_dev, DeviceState 
> *dev,
>  Error **errp)
>  {
> @@ -765,6 +781,22 @@ static void virtio_scsi_hotplug(HotplugHandler 
> *hotplug_dev, DeviceState *dev,
>  SCSIDevice *sd = SCSI_DEVICE(dev);
>  
>  if (s->ctx && !s->dataplane_disabled) {
> +VirtIOSCSIBlkChangeNotifier *insert_notifier, *remove_notifier;
> +
> +insert_notifier = g_new0(VirtIOSCSIBlkChangeNotifier, 1);
> +insert_notifier->n.notify = virtio_scsi_blk_insert_notifier;
> +insert_notifier->s = s;
> +insert_notifier->sd = sd;
> +blk_add_insert_bs_notifier(sd->conf.blk, _notifier->n);
> +QTAILQ_INSERT_TAIL(>insert_notifiers, insert_notifier, next);
> +
> +remove_notifier = g_new0(VirtIOSCSIBlkChangeNotifier, 1);
> +remove_notifier->n.notify = virtio_scsi_blk_remove_notifier;
> +remove_notifier->s = s;
> +remove_notifier->sd = sd;
> +blk_add_remove_bs_notifier(sd->conf.blk, _notifier->n);
> +QTAILQ_INSERT_TAIL(>remove_notifiers, remove_notifier, next);
> +
>  if (blk_op_is_blocked(sd->conf.blk, BLOCK_OP_TYPE_DATAPLANE, errp)) {
>  return;
>  }

If we take the error path here, won't we have dangling pointers in the
notifier list?

Kevin



Re: [Qemu-devel] [PATCH v8 05/16] virtio-scsi: Catch BDS-BB removal/insertion

2016-01-27 Thread Fam Zheng
On Wed, 01/27 18:59, Max Reitz wrote:
> Make use of the BDS-BB removal and insertion notifiers to remove or set
> up, respectively, virtio-scsi's op blockers.
> 
> Signed-off-by: Max Reitz 
> ---
>  hw/scsi/virtio-scsi.c   | 55 
> +
>  include/hw/virtio/virtio-scsi.h | 10 
>  2 files changed, 65 insertions(+)
> 
> diff --git a/hw/scsi/virtio-scsi.c b/hw/scsi/virtio-scsi.c
> index 607593c..b508b81 100644
> --- a/hw/scsi/virtio-scsi.c
> +++ b/hw/scsi/virtio-scsi.c
> @@ -757,6 +757,22 @@ static void virtio_scsi_change(SCSIBus *bus, SCSIDevice 
> *dev, SCSISense sense)
>  }
>  }
>  
> +static void virtio_scsi_blk_insert_notifier(Notifier *n, void *data)
> +{
> +VirtIOSCSIBlkChangeNotifier *cn = DO_UPCAST(VirtIOSCSIBlkChangeNotifier,
> +n, n);
> +assert(cn->sd->conf.blk == data);
> +blk_op_block_all(cn->sd->conf.blk, cn->s->blocker);
> +}
> +
> +static void virtio_scsi_blk_remove_notifier(Notifier *n, void *data)
> +{
> +VirtIOSCSIBlkChangeNotifier *cn = DO_UPCAST(VirtIOSCSIBlkChangeNotifier,
> +n, n);
> +assert(cn->sd->conf.blk == data);
> +blk_op_unblock_all(cn->sd->conf.blk, cn->s->blocker);
> +}
> +
>  static void virtio_scsi_hotplug(HotplugHandler *hotplug_dev, DeviceState 
> *dev,
>  Error **errp)
>  {
> @@ -765,6 +781,22 @@ static void virtio_scsi_hotplug(HotplugHandler 
> *hotplug_dev, DeviceState *dev,
>  SCSIDevice *sd = SCSI_DEVICE(dev);
>  
>  if (s->ctx && !s->dataplane_disabled) {
> +VirtIOSCSIBlkChangeNotifier *insert_notifier, *remove_notifier;
> +
> +insert_notifier = g_new0(VirtIOSCSIBlkChangeNotifier, 1);
> +insert_notifier->n.notify = virtio_scsi_blk_insert_notifier;
> +insert_notifier->s = s;
> +insert_notifier->sd = sd;
> +blk_add_insert_bs_notifier(sd->conf.blk, _notifier->n);
> +QTAILQ_INSERT_TAIL(>insert_notifiers, insert_notifier, next);
> +
> +remove_notifier = g_new0(VirtIOSCSIBlkChangeNotifier, 1);
> +remove_notifier->n.notify = virtio_scsi_blk_remove_notifier;
> +remove_notifier->s = s;
> +remove_notifier->sd = sd;
> +blk_add_remove_bs_notifier(sd->conf.blk, _notifier->n);
> +QTAILQ_INSERT_TAIL(>remove_notifiers, remove_notifier, next);
> +
>  if (blk_op_is_blocked(sd->conf.blk, BLOCK_OP_TYPE_DATAPLANE, errp)) {
>  return;
>  }
> @@ -787,6 +819,7 @@ static void virtio_scsi_hotunplug(HotplugHandler 
> *hotplug_dev, DeviceState *dev,
>  VirtIODevice *vdev = VIRTIO_DEVICE(hotplug_dev);
>  VirtIOSCSI *s = VIRTIO_SCSI(vdev);
>  SCSIDevice *sd = SCSI_DEVICE(dev);
> +VirtIOSCSIBlkChangeNotifier *insert_notifier, *remove_notifier;
>  
>  if (virtio_vdev_has_feature(vdev, VIRTIO_SCSI_F_HOTPLUG)) {
>  virtio_scsi_push_event(s, sd,
> @@ -797,6 +830,25 @@ static void virtio_scsi_hotunplug(HotplugHandler 
> *hotplug_dev, DeviceState *dev,
>  if (s->ctx) {
>  blk_op_unblock_all(sd->conf.blk, s->blocker);
>  }
> +
> +QTAILQ_FOREACH(insert_notifier, >insert_notifiers, next) {
> +if (insert_notifier->sd == sd) {
> +notifier_remove(_notifier->n);
> +QTAILQ_REMOVE(>insert_notifiers, insert_notifier, next);
> +g_free(insert_notifier);
> +break;
> +}
> +}
> +
> +QTAILQ_FOREACH(remove_notifier, >remove_notifiers, next) {
> +if (remove_notifier->sd == sd) {
> +notifier_remove(_notifier->n);
> +QTAILQ_REMOVE(>remove_notifiers, remove_notifier, next);
> +g_free(remove_notifier);
> +break;
> +}
> +}
> +
>  qdev_simple_device_unplug_cb(hotplug_dev, dev, errp);
>  }
>  
> @@ -911,6 +963,9 @@ static void virtio_scsi_device_realize(DeviceState *dev, 
> Error **errp)
>  add_migration_state_change_notifier(>migration_state_notifier);
>  
>  error_setg(>blocker, "block device is in use by data plane");
> +
> +QTAILQ_INIT(>insert_notifiers);
> +QTAILQ_INIT(>remove_notifiers);
>  }
>  
>  static void virtio_scsi_instance_init(Object *obj)
> diff --git a/include/hw/virtio/virtio-scsi.h b/include/hw/virtio/virtio-scsi.h
> index 088fe9f..0394eb2 100644
> --- a/include/hw/virtio/virtio-scsi.h
> +++ b/include/hw/virtio/virtio-scsi.h
> @@ -76,6 +76,13 @@ typedef struct VirtIOSCSICommon {
>  VirtQueue **cmd_vqs;
>  } VirtIOSCSICommon;
>  
> +typedef struct VirtIOSCSIBlkChangeNotifier {
> +Notifier n;
> +struct VirtIOSCSI *s;
> +SCSIDevice *sd;
> +QTAILQ_ENTRY(VirtIOSCSIBlkChangeNotifier) next;
> +} VirtIOSCSIBlkChangeNotifier;
> +
>  typedef struct VirtIOSCSI {
>  VirtIOSCSICommon parent_obj;
>  
> @@ -86,6 +93,9 @@ typedef struct VirtIOSCSI {
>  /* Fields for dataplane below */
>  AioContext *ctx; /* one iothread per 

[Qemu-devel] [PATCH v8 05/16] virtio-scsi: Catch BDS-BB removal/insertion

2016-01-27 Thread Max Reitz
Make use of the BDS-BB removal and insertion notifiers to remove or set
up, respectively, virtio-scsi's op blockers.

Signed-off-by: Max Reitz 
---
 hw/scsi/virtio-scsi.c   | 55 +
 include/hw/virtio/virtio-scsi.h | 10 
 2 files changed, 65 insertions(+)

diff --git a/hw/scsi/virtio-scsi.c b/hw/scsi/virtio-scsi.c
index 607593c..b508b81 100644
--- a/hw/scsi/virtio-scsi.c
+++ b/hw/scsi/virtio-scsi.c
@@ -757,6 +757,22 @@ static void virtio_scsi_change(SCSIBus *bus, SCSIDevice 
*dev, SCSISense sense)
 }
 }
 
+static void virtio_scsi_blk_insert_notifier(Notifier *n, void *data)
+{
+VirtIOSCSIBlkChangeNotifier *cn = DO_UPCAST(VirtIOSCSIBlkChangeNotifier,
+n, n);
+assert(cn->sd->conf.blk == data);
+blk_op_block_all(cn->sd->conf.blk, cn->s->blocker);
+}
+
+static void virtio_scsi_blk_remove_notifier(Notifier *n, void *data)
+{
+VirtIOSCSIBlkChangeNotifier *cn = DO_UPCAST(VirtIOSCSIBlkChangeNotifier,
+n, n);
+assert(cn->sd->conf.blk == data);
+blk_op_unblock_all(cn->sd->conf.blk, cn->s->blocker);
+}
+
 static void virtio_scsi_hotplug(HotplugHandler *hotplug_dev, DeviceState *dev,
 Error **errp)
 {
@@ -765,6 +781,22 @@ static void virtio_scsi_hotplug(HotplugHandler 
*hotplug_dev, DeviceState *dev,
 SCSIDevice *sd = SCSI_DEVICE(dev);
 
 if (s->ctx && !s->dataplane_disabled) {
+VirtIOSCSIBlkChangeNotifier *insert_notifier, *remove_notifier;
+
+insert_notifier = g_new0(VirtIOSCSIBlkChangeNotifier, 1);
+insert_notifier->n.notify = virtio_scsi_blk_insert_notifier;
+insert_notifier->s = s;
+insert_notifier->sd = sd;
+blk_add_insert_bs_notifier(sd->conf.blk, _notifier->n);
+QTAILQ_INSERT_TAIL(>insert_notifiers, insert_notifier, next);
+
+remove_notifier = g_new0(VirtIOSCSIBlkChangeNotifier, 1);
+remove_notifier->n.notify = virtio_scsi_blk_remove_notifier;
+remove_notifier->s = s;
+remove_notifier->sd = sd;
+blk_add_remove_bs_notifier(sd->conf.blk, _notifier->n);
+QTAILQ_INSERT_TAIL(>remove_notifiers, remove_notifier, next);
+
 if (blk_op_is_blocked(sd->conf.blk, BLOCK_OP_TYPE_DATAPLANE, errp)) {
 return;
 }
@@ -787,6 +819,7 @@ static void virtio_scsi_hotunplug(HotplugHandler 
*hotplug_dev, DeviceState *dev,
 VirtIODevice *vdev = VIRTIO_DEVICE(hotplug_dev);
 VirtIOSCSI *s = VIRTIO_SCSI(vdev);
 SCSIDevice *sd = SCSI_DEVICE(dev);
+VirtIOSCSIBlkChangeNotifier *insert_notifier, *remove_notifier;
 
 if (virtio_vdev_has_feature(vdev, VIRTIO_SCSI_F_HOTPLUG)) {
 virtio_scsi_push_event(s, sd,
@@ -797,6 +830,25 @@ static void virtio_scsi_hotunplug(HotplugHandler 
*hotplug_dev, DeviceState *dev,
 if (s->ctx) {
 blk_op_unblock_all(sd->conf.blk, s->blocker);
 }
+
+QTAILQ_FOREACH(insert_notifier, >insert_notifiers, next) {
+if (insert_notifier->sd == sd) {
+notifier_remove(_notifier->n);
+QTAILQ_REMOVE(>insert_notifiers, insert_notifier, next);
+g_free(insert_notifier);
+break;
+}
+}
+
+QTAILQ_FOREACH(remove_notifier, >remove_notifiers, next) {
+if (remove_notifier->sd == sd) {
+notifier_remove(_notifier->n);
+QTAILQ_REMOVE(>remove_notifiers, remove_notifier, next);
+g_free(remove_notifier);
+break;
+}
+}
+
 qdev_simple_device_unplug_cb(hotplug_dev, dev, errp);
 }
 
@@ -911,6 +963,9 @@ static void virtio_scsi_device_realize(DeviceState *dev, 
Error **errp)
 add_migration_state_change_notifier(>migration_state_notifier);
 
 error_setg(>blocker, "block device is in use by data plane");
+
+QTAILQ_INIT(>insert_notifiers);
+QTAILQ_INIT(>remove_notifiers);
 }
 
 static void virtio_scsi_instance_init(Object *obj)
diff --git a/include/hw/virtio/virtio-scsi.h b/include/hw/virtio/virtio-scsi.h
index 088fe9f..0394eb2 100644
--- a/include/hw/virtio/virtio-scsi.h
+++ b/include/hw/virtio/virtio-scsi.h
@@ -76,6 +76,13 @@ typedef struct VirtIOSCSICommon {
 VirtQueue **cmd_vqs;
 } VirtIOSCSICommon;
 
+typedef struct VirtIOSCSIBlkChangeNotifier {
+Notifier n;
+struct VirtIOSCSI *s;
+SCSIDevice *sd;
+QTAILQ_ENTRY(VirtIOSCSIBlkChangeNotifier) next;
+} VirtIOSCSIBlkChangeNotifier;
+
 typedef struct VirtIOSCSI {
 VirtIOSCSICommon parent_obj;
 
@@ -86,6 +93,9 @@ typedef struct VirtIOSCSI {
 /* Fields for dataplane below */
 AioContext *ctx; /* one iothread per virtio-scsi-pci for now */
 
+QTAILQ_HEAD(, VirtIOSCSIBlkChangeNotifier) insert_notifiers;
+QTAILQ_HEAD(, VirtIOSCSIBlkChangeNotifier) remove_notifiers;
+
 /* Vring is used instead of vq in dataplane code, because of the underlying
  * memory layer thread safety */
 VirtIOSCSIVring