Re: [PATCH v2 09/11] vfio/iommufd: Make iommufd_cdev_*() return bool

["Cédric Le Goater" <clg@redhat.com>]

On 5/7/24 08:42, Zhenzhong Duan wrote:
> This is to follow the coding standand to return bool if 'Error **'
> is used to pass error.
> 
> The changed functions include:
> 
> iommufd_cdev_kvm_device_add
> iommufd_cdev_connect_and_bind
> iommufd_cdev_attach_ioas_hwpt
> iommufd_cdev_detach_ioas_hwpt
> iommufd_cdev_attach_container
> iommufd_cdev_get_info_iova_range
> 
> After the change, all functions in hw/vfio/iommufd.c follows the
> standand.
> 
> Suggested-by: Cédric Le Goater <clg@redhat.com>
> Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>


Reviewed-by: Cédric Le Goater <clg@redhat.com>

Thanks,

C.


> ---
>   hw/vfio/iommufd.c | 88 +++++++++++++++++++++--------------------------
>   1 file changed, 39 insertions(+), 49 deletions(-)
> 
> diff --git a/hw/vfio/iommufd.c b/hw/vfio/iommufd.c
> index 4c6992fca1..84c86b970e 100644
> --- a/hw/vfio/iommufd.c
> +++ b/hw/vfio/iommufd.c
> @@ -49,9 +49,9 @@ static int iommufd_cdev_unmap(const VFIOContainerBase *bcontainer,
>                                        container->ioas_id, iova, size);
>   }
>   
> -static int iommufd_cdev_kvm_device_add(VFIODevice *vbasedev, Error **errp)
> +static bool iommufd_cdev_kvm_device_add(VFIODevice *vbasedev, Error **errp)
>   {
> -    return vfio_kvm_device_add_fd(vbasedev->fd, errp);
> +    return !vfio_kvm_device_add_fd(vbasedev->fd, errp);
>   }
>   
>   static void iommufd_cdev_kvm_device_del(VFIODevice *vbasedev)
> @@ -63,18 +63,16 @@ static void iommufd_cdev_kvm_device_del(VFIODevice *vbasedev)
>       }
>   }
>   
> -static int iommufd_cdev_connect_and_bind(VFIODevice *vbasedev, Error **errp)
> +static bool iommufd_cdev_connect_and_bind(VFIODevice *vbasedev, Error **errp)
>   {
>       IOMMUFDBackend *iommufd = vbasedev->iommufd;
>       struct vfio_device_bind_iommufd bind = {
>           .argsz = sizeof(bind),
>           .flags = 0,
>       };
> -    int ret;
>   
> -    ret = iommufd_backend_connect(iommufd, errp);
> -    if (ret) {
> -        return ret;
> +    if (iommufd_backend_connect(iommufd, errp)) {
> +        return false;
>       }
>   
>       /*
> @@ -82,15 +80,13 @@ static int iommufd_cdev_connect_and_bind(VFIODevice *vbasedev, Error **errp)
>        * in KVM. Especially for some emulated devices, it requires
>        * to have kvm information in the device open.
>        */
> -    ret = iommufd_cdev_kvm_device_add(vbasedev, errp);
> -    if (ret) {
> +    if (!iommufd_cdev_kvm_device_add(vbasedev, errp)) {
>           goto err_kvm_device_add;
>       }
>   
>       /* Bind device to iommufd */
>       bind.iommufd = iommufd->fd;
> -    ret = ioctl(vbasedev->fd, VFIO_DEVICE_BIND_IOMMUFD, &bind);
> -    if (ret) {
> +    if (ioctl(vbasedev->fd, VFIO_DEVICE_BIND_IOMMUFD, &bind)) {
>           error_setg_errno(errp, errno, "error bind device fd=%d to iommufd=%d",
>                            vbasedev->fd, bind.iommufd);
>           goto err_bind;
> @@ -99,12 +95,12 @@ static int iommufd_cdev_connect_and_bind(VFIODevice *vbasedev, Error **errp)
>       vbasedev->devid = bind.out_devid;
>       trace_iommufd_cdev_connect_and_bind(bind.iommufd, vbasedev->name,
>                                           vbasedev->fd, vbasedev->devid);
> -    return ret;
> +    return true;
>   err_bind:
>       iommufd_cdev_kvm_device_del(vbasedev);
>   err_kvm_device_add:
>       iommufd_backend_disconnect(iommufd);
> -    return ret;
> +    return false;
>   }
>   
>   static void iommufd_cdev_unbind_and_disconnect(VFIODevice *vbasedev)
> @@ -176,10 +172,10 @@ out:
>       return ret;
>   }
>   
> -static int iommufd_cdev_attach_ioas_hwpt(VFIODevice *vbasedev, uint32_t id,
> +static bool iommufd_cdev_attach_ioas_hwpt(VFIODevice *vbasedev, uint32_t id,
>                                            Error **errp)
>   {
> -    int ret, iommufd = vbasedev->iommufd->fd;
> +    int iommufd = vbasedev->iommufd->fd;
>       struct vfio_device_attach_iommufd_pt attach_data = {
>           .argsz = sizeof(attach_data),
>           .flags = 0,
> @@ -187,38 +183,38 @@ static int iommufd_cdev_attach_ioas_hwpt(VFIODevice *vbasedev, uint32_t id,
>       };
>   
>       /* Attach device to an IOAS or hwpt within iommufd */
> -    ret = ioctl(vbasedev->fd, VFIO_DEVICE_ATTACH_IOMMUFD_PT, &attach_data);
> -    if (ret) {
> +    if (ioctl(vbasedev->fd, VFIO_DEVICE_ATTACH_IOMMUFD_PT, &attach_data)) {
>           error_setg_errno(errp, errno,
>                            "[iommufd=%d] error attach %s (%d) to id=%d",
>                            iommufd, vbasedev->name, vbasedev->fd, id);
> -    } else {
> -        trace_iommufd_cdev_attach_ioas_hwpt(iommufd, vbasedev->name,
> -                                            vbasedev->fd, id);
> +        return false;
>       }
> -    return ret;
> +
> +    trace_iommufd_cdev_attach_ioas_hwpt(iommufd, vbasedev->name,
> +                                        vbasedev->fd, id);
> +    return true;
>   }
>   
> -static int iommufd_cdev_detach_ioas_hwpt(VFIODevice *vbasedev, Error **errp)
> +static bool iommufd_cdev_detach_ioas_hwpt(VFIODevice *vbasedev, Error **errp)
>   {
> -    int ret, iommufd = vbasedev->iommufd->fd;
> +    int iommufd = vbasedev->iommufd->fd;
>       struct vfio_device_detach_iommufd_pt detach_data = {
>           .argsz = sizeof(detach_data),
>           .flags = 0,
>       };
>   
> -    ret = ioctl(vbasedev->fd, VFIO_DEVICE_DETACH_IOMMUFD_PT, &detach_data);
> -    if (ret) {
> +    if (ioctl(vbasedev->fd, VFIO_DEVICE_DETACH_IOMMUFD_PT, &detach_data)) {
>           error_setg_errno(errp, errno, "detach %s failed", vbasedev->name);
> -    } else {
> -        trace_iommufd_cdev_detach_ioas_hwpt(iommufd, vbasedev->name);
> +        return false;
>       }
> -    return ret;
> +
> +    trace_iommufd_cdev_detach_ioas_hwpt(iommufd, vbasedev->name);
> +    return true;
>   }
>   
> -static int iommufd_cdev_attach_container(VFIODevice *vbasedev,
> -                                         VFIOIOMMUFDContainer *container,
> -                                         Error **errp)
> +static bool iommufd_cdev_attach_container(VFIODevice *vbasedev,
> +                                          VFIOIOMMUFDContainer *container,
> +                                          Error **errp)
>   {
>       return iommufd_cdev_attach_ioas_hwpt(vbasedev, container->ioas_id, errp);
>   }
> @@ -228,7 +224,7 @@ static void iommufd_cdev_detach_container(VFIODevice *vbasedev,
>   {
>       Error *err = NULL;
>   
> -    if (iommufd_cdev_detach_ioas_hwpt(vbasedev, &err)) {
> +    if (!iommufd_cdev_detach_ioas_hwpt(vbasedev, &err)) {
>           error_report_err(err);
>       }
>   }
> @@ -254,20 +250,19 @@ static int iommufd_cdev_ram_block_discard_disable(bool state)
>       return ram_block_uncoordinated_discard_disable(state);
>   }
>   
> -static int iommufd_cdev_get_info_iova_range(VFIOIOMMUFDContainer *container,
> -                                            uint32_t ioas_id, Error **errp)
> +static bool iommufd_cdev_get_info_iova_range(VFIOIOMMUFDContainer *container,
> +                                             uint32_t ioas_id, Error **errp)
>   {
>       VFIOContainerBase *bcontainer = &container->bcontainer;
>       g_autofree struct iommu_ioas_iova_ranges *info = NULL;
>       struct iommu_iova_range *iova_ranges;
> -    int ret, sz, fd = container->be->fd;
> +    int sz, fd = container->be->fd;
>   
>       info = g_malloc0(sizeof(*info));
>       info->size = sizeof(*info);
>       info->ioas_id = ioas_id;
>   
> -    ret = ioctl(fd, IOMMU_IOAS_IOVA_RANGES, info);
> -    if (ret && errno != EMSGSIZE) {
> +    if (ioctl(fd, IOMMU_IOAS_IOVA_RANGES, info) && errno != EMSGSIZE) {
>           goto error;
>       }
>   
> @@ -275,8 +270,7 @@ static int iommufd_cdev_get_info_iova_range(VFIOIOMMUFDContainer *container,
>       info = g_realloc(info, sizeof(*info) + sz);
>       info->allowed_iovas = (uintptr_t)(info + 1);
>   
> -    ret = ioctl(fd, IOMMU_IOAS_IOVA_RANGES, info);
> -    if (ret) {
> +    if (ioctl(fd, IOMMU_IOAS_IOVA_RANGES, info)) {
>           goto error;
>       }
>   
> @@ -291,12 +285,11 @@ static int iommufd_cdev_get_info_iova_range(VFIOIOMMUFDContainer *container,
>       }
>       bcontainer->pgsizes = info->out_iova_alignment;
>   
> -    return 0;
> +    return true;
>   
>   error:
> -    ret = -errno;
>       error_setg_errno(errp, errno, "Cannot get IOVA ranges");
> -    return ret;
> +    return false;
>   }
>   
>   static bool iommufd_cdev_attach(const char *name, VFIODevice *vbasedev,
> @@ -322,8 +315,7 @@ static bool iommufd_cdev_attach(const char *name, VFIODevice *vbasedev,
>           devfd = vbasedev->fd;
>       }
>   
> -    ret = iommufd_cdev_connect_and_bind(vbasedev, errp);
> -    if (ret) {
> +    if (!iommufd_cdev_connect_and_bind(vbasedev, errp)) {
>           goto err_connect_bind;
>       }
>   
> @@ -336,7 +328,7 @@ static bool iommufd_cdev_attach(const char *name, VFIODevice *vbasedev,
>               vbasedev->iommufd != container->be) {
>               continue;
>           }
> -        if (iommufd_cdev_attach_container(vbasedev, container, &err)) {
> +        if (!iommufd_cdev_attach_container(vbasedev, container, &err)) {
>               const char *msg = error_get_pretty(err);
>   
>               trace_iommufd_cdev_fail_attach_existing_container(msg);
> @@ -369,8 +361,7 @@ static bool iommufd_cdev_attach(const char *name, VFIODevice *vbasedev,
>       vfio_container_init(bcontainer, space, iommufd_vioc);
>       QLIST_INSERT_HEAD(&space->containers, bcontainer, next);
>   
> -    ret = iommufd_cdev_attach_container(vbasedev, container, errp);
> -    if (ret) {
> +    if (!iommufd_cdev_attach_container(vbasedev, container, errp)) {
>           goto err_attach_container;
>       }
>   
> @@ -379,8 +370,7 @@ static bool iommufd_cdev_attach(const char *name, VFIODevice *vbasedev,
>           goto err_discard_disable;
>       }
>   
> -    ret = iommufd_cdev_get_info_iova_range(container, ioas_id, &err);
> -    if (ret) {
> +    if (!iommufd_cdev_get_info_iova_range(container, ioas_id, &err)) {
>           error_append_hint(&err,
>                      "Fallback to default 64bit IOVA range and 4K page size\n");
>           warn_report_err(err);