Re: [PATCH v2 03/11] vfio: Make VFIOIOMMUClass::attach_device() and its wrapper return bool

["Cédric Le Goater" <clg@redhat.com>]

On 5/7/24 08:42, Zhenzhong Duan wrote:
> Make VFIOIOMMUClass::attach_device() and its wrapper function
> vfio_attach_device() return bool.
> 
> This is to follow the coding standand to return bool if 'Error **'
> is used to pass error.
> 
> Suggested-by: Cédric Le Goater <clg@redhat.com>
> Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
> ---
>   include/hw/vfio/vfio-common.h         |  4 ++--
>   include/hw/vfio/vfio-container-base.h |  4 ++--
>   hw/vfio/ap.c                          |  6 ++----
>   hw/vfio/ccw.c                         |  6 ++----
>   hw/vfio/common.c                      |  4 ++--
>   hw/vfio/container.c                   | 14 +++++++-------
>   hw/vfio/iommufd.c                     | 11 +++++------
>   hw/vfio/pci.c                         |  5 ++---
>   hw/vfio/platform.c                    |  7 +++----
>   9 files changed, 27 insertions(+), 34 deletions(-)
> 
> diff --git a/include/hw/vfio/vfio-common.h b/include/hw/vfio/vfio-common.h
> index b9da6c08ef..a7b6fc8f46 100644
> --- a/include/hw/vfio/vfio-common.h
> +++ b/include/hw/vfio/vfio-common.h
> @@ -198,8 +198,8 @@ void vfio_region_exit(VFIORegion *region);
>   void vfio_region_finalize(VFIORegion *region);
>   void vfio_reset_handler(void *opaque);
>   struct vfio_device_info *vfio_get_device_info(int fd);
> -int vfio_attach_device(char *name, VFIODevice *vbasedev,
> -                       AddressSpace *as, Error **errp);
> +bool vfio_attach_device(char *name, VFIODevice *vbasedev,
> +                        AddressSpace *as, Error **errp);
>   void vfio_detach_device(VFIODevice *vbasedev);
>   
>   int vfio_kvm_device_add_fd(int fd, Error **errp);
> diff --git a/include/hw/vfio/vfio-container-base.h b/include/hw/vfio/vfio-container-base.h
> index 3582d5f97a..c839cfd9cb 100644
> --- a/include/hw/vfio/vfio-container-base.h
> +++ b/include/hw/vfio/vfio-container-base.h
> @@ -118,8 +118,8 @@ struct VFIOIOMMUClass {
>       int (*dma_unmap)(const VFIOContainerBase *bcontainer,
>                        hwaddr iova, ram_addr_t size,
>                        IOMMUTLBEntry *iotlb);
> -    int (*attach_device)(const char *name, VFIODevice *vbasedev,
> -                         AddressSpace *as, Error **errp);
> +    bool (*attach_device)(const char *name, VFIODevice *vbasedev,
> +                          AddressSpace *as, Error **errp);
>       void (*detach_device)(VFIODevice *vbasedev);
>       /* migration feature */
>       int (*set_dirty_page_tracking)(const VFIOContainerBase *bcontainer,
> diff --git a/hw/vfio/ap.c b/hw/vfio/ap.c
> index 7c4caa5938..d50600b702 100644
> --- a/hw/vfio/ap.c
> +++ b/hw/vfio/ap.c
> @@ -156,7 +156,6 @@ static void vfio_ap_unregister_irq_notifier(VFIOAPDevice *vapdev,
>   static void vfio_ap_realize(DeviceState *dev, Error **errp)
>   {
>       ERRP_GUARD();
> -    int ret;
>       Error *err = NULL;
>       VFIOAPDevice *vapdev = VFIO_AP_DEVICE(dev);
>       VFIODevice *vbasedev = &vapdev->vdev;
> @@ -165,9 +164,8 @@ static void vfio_ap_realize(DeviceState *dev, Error **errp)
>           return;
>       }
>   
> -    ret = vfio_attach_device(vbasedev->name, vbasedev,
> -                             &address_space_memory, errp);
> -    if (ret) {
> +    if (!vfio_attach_device(vbasedev->name, vbasedev,
> +                            &address_space_memory, errp)) {
>           goto error;
>       }
>   
> diff --git a/hw/vfio/ccw.c b/hw/vfio/ccw.c
> index 90e4a53437..782bd4bed7 100644
> --- a/hw/vfio/ccw.c
> +++ b/hw/vfio/ccw.c
> @@ -580,7 +580,6 @@ static void vfio_ccw_realize(DeviceState *dev, Error **errp)
>       S390CCWDeviceClass *cdc = S390_CCW_DEVICE_GET_CLASS(cdev);
>       VFIODevice *vbasedev = &vcdev->vdev;
>       Error *err = NULL;
> -    int ret;
>   
>       /* Call the class init function for subchannel. */
>       if (cdc->realize) {
> @@ -594,9 +593,8 @@ static void vfio_ccw_realize(DeviceState *dev, Error **errp)
>           return;
>       }
>   
> -    ret = vfio_attach_device(cdev->mdevid, vbasedev,
> -                             &address_space_memory, errp);
> -    if (ret) {
> +    if (!vfio_attach_device(cdev->mdevid, vbasedev,
> +                            &address_space_memory, errp)) {
>           goto out_attach_dev_err;
>       }
>   
> diff --git a/hw/vfio/common.c b/hw/vfio/common.c
> index 8f9cbdc026..890d30910e 100644
> --- a/hw/vfio/common.c
> +++ b/hw/vfio/common.c
> @@ -1492,8 +1492,8 @@ retry:
>       return info;
>   }
>   
> -int vfio_attach_device(char *name, VFIODevice *vbasedev,
> -                       AddressSpace *as, Error **errp)
> +bool vfio_attach_device(char *name, VFIODevice *vbasedev,
> +                        AddressSpace *as, Error **errp)
>   {
>       const VFIOIOMMUClass *ops =
>           VFIO_IOMMU_CLASS(object_class_by_name(TYPE_VFIO_IOMMU_LEGACY));

This is still broken. No need to resend. I will update the code.


Thanks,

C.




> diff --git a/hw/vfio/container.c b/hw/vfio/container.c
> index 77bdec276e..ea3b145913 100644
> --- a/hw/vfio/container.c
> +++ b/hw/vfio/container.c
> @@ -908,8 +908,8 @@ static int vfio_device_groupid(VFIODevice *vbasedev, Error **errp)
>    * @name and @vbasedev->name are likely to be different depending
>    * on the type of the device, hence the need for passing @name
>    */
> -static int vfio_legacy_attach_device(const char *name, VFIODevice *vbasedev,
> -                                     AddressSpace *as, Error **errp)
> +static bool vfio_legacy_attach_device(const char *name, VFIODevice *vbasedev,
> +                                      AddressSpace *as, Error **errp)
>   {
>       int groupid = vfio_device_groupid(vbasedev, errp);
>       VFIODevice *vbasedev_iter;
> @@ -918,27 +918,27 @@ static int vfio_legacy_attach_device(const char *name, VFIODevice *vbasedev,
>       int ret;
>   
>       if (groupid < 0) {
> -        return groupid;
> +        return false;
>       }
>   
>       trace_vfio_attach_device(vbasedev->name, groupid);
>   
>       group = vfio_get_group(groupid, as, errp);
>       if (!group) {
> -        return -ENOENT;
> +        return false;
>       }
>   
>       QLIST_FOREACH(vbasedev_iter, &group->device_list, next) {
>           if (strcmp(vbasedev_iter->name, vbasedev->name) == 0) {
>               error_setg(errp, "device is already attached");
>               vfio_put_group(group);
> -            return -EBUSY;
> +            return false;
>           }
>       }
>       ret = vfio_get_device(group, name, vbasedev, errp);
>       if (ret) {
>           vfio_put_group(group);
> -        return ret;
> +        return false;
>       }
>   
>       bcontainer = &group->container->bcontainer;
> @@ -946,7 +946,7 @@ static int vfio_legacy_attach_device(const char *name, VFIODevice *vbasedev,
>       QLIST_INSERT_HEAD(&bcontainer->device_list, vbasedev, container_next);
>       QLIST_INSERT_HEAD(&vfio_device_list, vbasedev, global_next);
>   
> -    return ret;
> +    return true;
>   }
>   
>   static void vfio_legacy_detach_device(VFIODevice *vbasedev)
> diff --git a/hw/vfio/iommufd.c b/hw/vfio/iommufd.c
> index c644127972..4c6992fca1 100644
> --- a/hw/vfio/iommufd.c
> +++ b/hw/vfio/iommufd.c
> @@ -299,8 +299,8 @@ error:
>       return ret;
>   }
>   
> -static int iommufd_cdev_attach(const char *name, VFIODevice *vbasedev,
> -                               AddressSpace *as, Error **errp)
> +static bool iommufd_cdev_attach(const char *name, VFIODevice *vbasedev,
> +                                AddressSpace *as, Error **errp)
>   {
>       VFIOContainerBase *bcontainer;
>       VFIOIOMMUFDContainer *container;
> @@ -315,7 +315,7 @@ static int iommufd_cdev_attach(const char *name, VFIODevice *vbasedev,
>       if (vbasedev->fd < 0) {
>           devfd = iommufd_cdev_getfd(vbasedev->sysfsdev, errp);
>           if (devfd < 0) {
> -            return devfd;
> +            return false;
>           }
>           vbasedev->fd = devfd;
>       } else {
> @@ -392,7 +392,6 @@ static int iommufd_cdev_attach(const char *name, VFIODevice *vbasedev,
>       memory_listener_register(&bcontainer->listener, bcontainer->space->as);
>   
>       if (bcontainer->error) {
> -        ret = -1;
>           error_propagate_prepend(errp, bcontainer->error,
>                                   "memory listener initialization failed: ");
>           goto err_listener_register;
> @@ -431,7 +430,7 @@ found_container:
>   
>       trace_iommufd_cdev_device_info(vbasedev->name, devfd, vbasedev->num_irqs,
>                                      vbasedev->num_regions, vbasedev->flags);
> -    return 0;
> +    return true;
>   
>   err_listener_register:
>       iommufd_cdev_ram_block_discard_disable(false);
> @@ -444,7 +443,7 @@ err_alloc_ioas:
>       iommufd_cdev_unbind_and_disconnect(vbasedev);
>   err_connect_bind:
>       close(vbasedev->fd);
> -    return ret;
> +    return false;
>   }
>   
>   static void iommufd_cdev_detach(VFIODevice *vbasedev)
> diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
> index 576b21e2bb..d3beb15514 100644
> --- a/hw/vfio/pci.c
> +++ b/hw/vfio/pci.c
> @@ -3001,9 +3001,8 @@ static void vfio_realize(PCIDevice *pdev, Error **errp)
>           name = g_strdup(vbasedev->name);
>       }
>   
> -    ret = vfio_attach_device(name, vbasedev,
> -                             pci_device_iommu_address_space(pdev), errp);
> -    if (ret) {
> +    if (!vfio_attach_device(name, vbasedev,
> +                            pci_device_iommu_address_space(pdev), errp)) {
>           goto error;
>       }
>   
> diff --git a/hw/vfio/platform.c b/hw/vfio/platform.c
> index dcd2365fb3..2bd16096bb 100644
> --- a/hw/vfio/platform.c
> +++ b/hw/vfio/platform.c
> @@ -552,10 +552,9 @@ static int vfio_base_device_init(VFIODevice *vbasedev, Error **errp)
>           return ret;
>       }
>   
> -    ret = vfio_attach_device(vbasedev->name, vbasedev,
> -                             &address_space_memory, errp);
> -    if (ret) {
> -        return ret;
> +    if (!vfio_attach_device(vbasedev->name, vbasedev,
> +                            &address_space_memory, errp)) {
> +        return -EINVAL;
>       }
>   
>       ret = vfio_populate_device(vbasedev, errp);