Re: [Qemu-devel] [PATCH] vfio-ccw: use vfio_set_irq_signaling

[Eric Farman <farman@linux.ibm.com>]

On 6/14/19 5:27 AM, Cornelia Huck wrote:
> Use the new helper.
> 
> Signed-off-by: Cornelia Huck <cohuck@redhat.com>
> ---
>  hw/vfio/ccw.c | 68 +++++++++++----------------------------------------
>  1 file changed, 14 insertions(+), 54 deletions(-)
> 
> diff --git a/hw/vfio/ccw.c b/hw/vfio/ccw.c
> index 03a2becb3ec9..3dc08721a3db 100644
> --- a/hw/vfio/ccw.c
> +++ b/hw/vfio/ccw.c
> @@ -197,10 +197,7 @@ read_err:
>  static void vfio_ccw_register_io_notifier(VFIOCCWDevice *vcdev, Error **errp)
>  {
>      VFIODevice *vdev = &vcdev->vdev;
> -    struct vfio_irq_info *irq_info;
> -    struct vfio_irq_set *irq_set;
> -    size_t argsz;
> -    int32_t *pfd;
> +    int fd;
>  
>      if (vdev->num_irqs < VFIO_CCW_IO_IRQ_INDEX + 1) {
>          error_setg(errp, "vfio: unexpected number of io irqs %u",
> @@ -208,72 +205,35 @@ static void vfio_ccw_register_io_notifier(VFIOCCWDevice *vcdev, Error **errp)
>          return;
>      }
>  
> -    argsz = sizeof(*irq_info);
> -    irq_info = g_malloc0(argsz);
> -    irq_info->index = VFIO_CCW_IO_IRQ_INDEX;
> -    irq_info->argsz = argsz;
> -    if (ioctl(vdev->fd, VFIO_DEVICE_GET_IRQ_INFO,
> -              irq_info) < 0 || irq_info->count < 1) {
> -        error_setg_errno(errp, errno, "vfio: Error getting irq info");
> -        goto out_free_info;
> -    }
> -

Don't we still need this hunk?  (And the out_free_info label stuff that
cleans it up.)  I don't see vfio_set_irq_signaling() covering it.

>      if (event_notifier_init(&vcdev->io_notifier, 0)) {
>          error_setg_errno(errp, errno,
>                           "vfio: Unable to init event notifier for IO");
> -        goto out_free_info;
> +        return;
>      }
>  
> -    argsz = sizeof(*irq_set) + sizeof(*pfd);
> -    irq_set = g_malloc0(argsz);
> -    irq_set->argsz = argsz;
> -    irq_set->flags = VFIO_IRQ_SET_DATA_EVENTFD |
> -                     VFIO_IRQ_SET_ACTION_TRIGGER;
> -    irq_set->index = VFIO_CCW_IO_IRQ_INDEX;
> -    irq_set->start = 0;
> -    irq_set->count = 1;
> -    pfd = (int32_t *) &irq_set->data;
> -
> -    *pfd = event_notifier_get_fd(&vcdev->io_notifier);
> -    qemu_set_fd_handler(*pfd, vfio_ccw_io_notifier_handler, NULL, vcdev);
> -    if (ioctl(vdev->fd, VFIO_DEVICE_SET_IRQS, irq_set)) {
> -        error_setg(errp, "vfio: Failed to set up io notification");
> -        qemu_set_fd_handler(*pfd, NULL, NULL, vcdev);
> +    fd = event_notifier_get_fd(&vcdev->io_notifier);
> +    qemu_set_fd_handler(fd, vfio_ccw_io_notifier_handler, NULL, vcdev);
> +
> +    if (vfio_set_irq_signaling(vdev, VFIO_CCW_IO_IRQ_INDEX, 0,
> +                               VFIO_IRQ_SET_ACTION_TRIGGER, fd, errp)) {
> +        qemu_set_fd_handler(fd, NULL, NULL, vcdev);

This sure looks nice though.  :)

>          event_notifier_cleanup(&vcdev->io_notifier);
>      }
> -
> -    g_free(irq_set);
> -
> -out_free_info:
> -    g_free(irq_info);
>  }
>  
>  static void vfio_ccw_unregister_io_notifier(VFIOCCWDevice *vcdev)
>  {
> -    struct vfio_irq_set *irq_set;
> -    size_t argsz;
> -    int32_t *pfd;
> -
> -    argsz = sizeof(*irq_set) + sizeof(*pfd);
> -    irq_set = g_malloc0(argsz);
> -    irq_set->argsz = argsz;
> -    irq_set->flags = VFIO_IRQ_SET_DATA_EVENTFD |
> -                     VFIO_IRQ_SET_ACTION_TRIGGER;
> -    irq_set->index = VFIO_CCW_IO_IRQ_INDEX;
> -    irq_set->start = 0;
> -    irq_set->count = 1;
> -    pfd = (int32_t *) &irq_set->data;
> -    *pfd = -1;
> -
> -    if (ioctl(vcdev->vdev.fd, VFIO_DEVICE_SET_IRQS, irq_set)) {
> -        error_report("vfio: Failed to de-assign device io fd: %m");
> +    Error *err = NULL;
> +
> +    vfio_set_irq_signaling(&vcdev->vdev, VFIO_CCW_IO_IRQ_INDEX, 0,
> +                           VFIO_IRQ_SET_ACTION_TRIGGER, -1, &err);
> +    if (err) {
> +        error_reportf_err(err, VFIO_MSG_PREFIX, vcdev->vdev.name);
>      }
>  
>      qemu_set_fd_handler(event_notifier_get_fd(&vcdev->io_notifier),
>                          NULL, NULL, vcdev);
>      event_notifier_cleanup(&vcdev->io_notifier);
> -
> -    g_free(irq_set);
>  }
>  
>  static void vfio_ccw_get_region(VFIOCCWDevice *vcdev, Error **errp)
>